Data Type[1][2]

movefile()

datetime()[301][302]

Here’s how to use datetime() function.

datetime(datetimeExp)[303][304]

Description:

Adjust the precision of the datetime expression and return it.

Syntax:

datetime(datetimeExp)

Note:

The function adjusts the precision of datetimeExp and returns it. By default, the precision is the day.

Parameter:

datetimeExp

Datetime value

Options:

@m	Measure to minute
@s	Measure to second

Return value:

Datetime value

Example:

datetime(now())	2013-12-09 00:00:00
datetime@m(now())	2013-12-09 16:56:00
datetime@s(now())	2013-12-09 16:56:45

Related functions:

datetime()[305][306]

Description:

Convert the string or long integer to datetime value.

Syntax:

datetime(string{, format })	Convert the data type of string to datetime type according to the format defined by format; if parameter format doesn’t exist, the format of string of string type should be the same as the format of datatime value in configuration information
datetime(long)	Convert long of long integer type to datetime value
datetime(date,time)	Concatenate date type data and time type data into data of datetime type
datetime(y,m,d,h,m,s)	Convert y,m,d,h,m,s of integer type to datetime data
datetime(ym,d,h,m,s)	Convert integer ym, d, h, m, s into datetime data

Note:

The format of string should match format.

Parameters:

string	String
format	Format string
long	Long integer counted in microseconds
date	Date type
time	Time type
y	Positive integer, year
m	Positive integer, month
ym	6-bit positive integer interpreted as year and month
d	Positive integer, day
h	Positive integer, hour
m	Positive integer, minute
s	Positive integer, second

Return value:

Datetime type data

Example:

datetime("2006-01-01 10:20:30")	2006-01-01 10:20:30
datetime("12/28/1972 10:23:43","MM/dd/yyyy HH:mm:ss")	1972-12-28 10:23:43
datetime("2006-01-01 10:20:30:111")	2006-01-01 10:20:30
datetime(12345)	1970-01-01 08:00:12
datetime(date("1982-08-09"),time("12:12:12"))	1982-08-09 12:12:12
datetime(2006,01,01,-10,-20,30) datetime(200601,01,-10,-20,30)	2005-12-31 13:40:30 2005-12-31 13:40:30

Related functions:

date()

time()

date(datetimeExp)

datetime(datetimeExp)

time(datetimeExp)

day()[307][308]

Description:

Get the day from a date value.

Syntax:

day(dateExp)

Note:

The function gets the day from dateExp of date type.

Parameters:

dateExp

Date expression whose result must be the date or the string of Chinese date and time format.

Options:

@w	Get the day of the week from the specified date. For Sunday, return 1; For Monday, return 2, and so on. By default, get the day of the month from the specified date.

Return value:

Integer

Example:

day(datetime("19800227","yyyyMMdd"))	27
day(datetime(12345))	1
day(datetime("2006-01-15 10:20:30"))	15
day@w(datetime("19800227","yyyyMMdd"))	4
day@w(datetime("2006-01-15 10:20:30"))	1

Related functions:

year()

month()

hour()

minute()

second()

days()[309][310]

Description:

Get the number of days of the year, quarter or month to which the specified date belongs.

Syntax:

days(dateExp)

Note:

The function gets the number of days of the year, quarter or month to which the specified date dateExp belongs.

Parameters:

dateExp

A date or a date string of standard format

Options:

Get the number of days of the quarter to which the specified date belongs

Get the number of days of the year to which the specified date belongs

By default get the number of days of the month to which the specified date belongs

Return value:

Integer

Example:

days(datetime("19800227","yyyyMMdd"))	29
days(datetime("2006-01-15 10:20:30"))	31
days@y(datetime("19800227","yyyyMMdd"))	366
days@q(datetime("2006-01-15 10:20:30"))	90

decimal()[311][312]

Description:

Convert a string or numeric value to a big decimal number.

Syntax:

decimal(stringExp)

decimal(numberExp)

Note:

The parameter stringExp is a string consisting of a number (and sometimes a decimal point).

The parameter numberExp is a numeric value which is less than or equal to 64 bits. For values more than 64 bits, you will have to use the stringExp to represent them.

Parameters:

stringExp	A specified numeric string, which may contain a decimal point.
numberExp	The numeric value which is less than or equal to 64 bits.

Return value:

Big decimal number

Example:

decimal("123456789012345678901234567890")	123456789012345678901234567890
decimal(1234567890123456)	1234567890123456 (BigDecimal type)

Related functions:

float()

int()

long()

number()

string()

delete()[313][314]

Here’s how to use delete() function.

T.delete()[315][316]

Description:

Delete specified records from a table sequence.

Syntax:

T.delete(k)	Delete the k^th record
T.delete(p)	Delete the records whose sequence numbers exist in p
T.delete(A)	Delete the records that exist in A

Note:

The function deletes the specified records from table sequence T, and automatically updates the index, if any, and checks distinctness. The deleted records will be always saved in the delete buffer.

Parameters:

T	A table sequence
k	A positive integer, which specifies the position of a record to be deleted
p	An integer sequence with the length of n, which specifies the positions of the records to be deleted
A	A sequence, which specifies the records to be deleted

Options:

@n Return the deleted record or a record sequence of the deleted records

Return value:

The table sequence T, some records of which have been deleted

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1.delete(1)		Delete the first record
3	=A1.delete([2,4,6])		Delete the second, the forth and the sixth records.
4	=A1.select(EID>5)
5	=A1.delete(A4)		Delete the records whose EID is more than 5.
6		=A1.delete@n(1)	Return the deleted record

Note:

We use the store address, instead of the field names or field values, to judge whether the records specified by A exist in T. So to delete the specified records , we generally use the function T.delete(T.select(…)) to locate them.

Related functions:

T.insert()

A.delete()

A.delete()[317][318]

Description:

Delete specified members from a sequence.

Syntax:

A.delete(k)	Delete the k^th member
A.delete(p)	Delete the members whose sequence numbers exist in p

Note:

The function deletes the k^th member or the members whose sequence numbers exist in p from sequence A, and automatically updates the index, if any, and checks distinctness.

Parameters:

A	A sequence
k	A positive integer that indicates the position of a member to be deleted in the sequence
p	An integer sequence with the length of n that specifies the positions of the members to be deleted

Options:

@n	Return the deleted record or a record sequence of the deleted records

Return value:

A sequence

Example:

	A
1	=["a","c","d","e","f"]
2	=A1.delete([2,4,5])	[a,d]
3	=demo.query("select * from STUDENTS")
4	=A3.delete@n(2)	Return the deleted record

Related functions:

A.insert()

A.modify()

T.delete()

T.delete(P)^{^[319]}^{^[320]}

Description:

Delete specified record(s) from acomposite table.

Syntax:

T.delete(P)

Note:

The function deletes from entity table T the records that matches key values of record sequence P. If T has an index, then update it automatically. If T is the base table having an attached table, delete records having same dimensions from the attached table.

Parameters:

T	An entity table
P	A record sequence having same structure as T

Options:

@n	Return the deleted record(s)

Example:

	A
1	=file("D:\\emp3.ctx")
2	=A1.create(#EID,NAME;EID)	Create a composite table where EID field is the key by which records are segmented
3	=demo.cursor("select EID,NAME from employee where EID< 10")
4	=A2.append(A3)	Append data to the base table
5	=A2.attach(table3,GENDER)	Add an attached table to the base table
6	=demo.cursor("select EID,GENDER from employee where EID< 10")
7	=A5.append(A6)	Append cursor records to the attached table
8	=demo.query("select EID,GENDER from employee where EID =3 ")	Return records of the table sequence where EID is 3
9	=A5.delete(A8)	Delete the records where EID is 3 from entity table table3
10	=demo.query("select EID,NAME from employee where EID =2")	Return records in the table sequence where EID is 2
11	=A2.delete@n(A10)	Return the deleted record

T.delete(P)^{^[321]}^{^[322]}

Description:

Delete specified records from a memory table.

Syntax:

T.delete(P)

Note:

The function matches memory table T’s primary key with primary key values of record sequence P and deletes from T the matching records, during which T’s primary key keeps its order. Will automatically update the index if T has one.

Parameters:

T	A memory table
P	A records sequence having the same structure as T

Options:

@n	Return the deleted records

Return value:

A memory table

Example:

	A
1	=demo. cursor ("select EID,NAME,GENDER from employee where EID< 10")	Return a cursor
2	=A1.memory()	Return a memory table
3	=A2.keys(EID)
4	=demo.query("select EID,NAME,GENDER from employee where EID =3 ")	Return records in the table sequence where EID is 3
5	=A2.delete(A4)	Delete records where EID is 3
6	=demo.query("select EID,NAME,GENDER from employee where EID =5 ")	Return records in the table sequence where EID is 5
7	=A2.delete@n(A6)	Return the deleted record

T.delete(P)^{^[323]}^{^[324]}

Description:

Delete specified records from a cluster table.

Syntax:

T.delete(P)

Note:

The function matches cluster table T’s primary key with primary key values of record sequence P and deletes from T the matching records. Will automatically update the index if T has one. Only records in a distributed cluster composite table can be deleted.

Parameters:

T	A cluster table
P	A record sequence of same structure as T

Example:

	A
1	=file@0@z("emp10.ctx",["192.168.0.118:8281"])
2	=A1.create()	Open a distributed cluster composite table
3	=demo.query("select EID,GENDER from employee where EID =3 ")	Return records of the table sequence where EID is 3
4	=A2.delete(A3)	Delete records from entity table table3 where EID is 3

deq()[325][326]

Description:

Compare the specified two dates.

Syntax:

deq(datetimeExp1,datetimeExp2)

Note:

The function compares two parameters - dateExp1 and dateExp2 - to see if they are equal.

Parameters:

datetimeExp1

Date or standard datetime format string

such as yyyy-MM-dd HH:mm:ss, yyyy-MM-dd, or HH:mm:ss

datetimeExp2

Date or standard datetime format string

such as yyyy-MM-dd HH:mm:ss, yyyy-MM-dd, or HH:mm:ss

Options:

@y	Accurate to the year
@q	Accurate to the quarter
@m	Accurate to the month
@t	Accurate to the ten-day period
@w	Accurate to the week
	Accurate to the day by default

Return value:

A boolean value

Example:

deq("1988-12-08","1988-12-07")	false
deq@y(date("1988-11-08"),date("1988-09-12"))	true
deq@m(date("1988-11-08"),date("1988-09-12"))	false
deq@q(date("1988-12-08"),date("1988-10-12"))	true
deq@t(date("1988-10-08"),date("1988-10-12"))	false
deq@w(date("1988-10-05"),date("1988-10-08"))	true

derive()[327][328]

Here’s how to use derive() function.

A.derive()[329][330]

Description:

Add one or more fields to a table sequence or a record sequence.

Syntax:

A.derive(xi:Fi,…)

Note:

The function adds Fi,… field(s) to table sequence/record sequence A to re-structure it as a table sequence with "original fields in P plus Fi,…", and then traverses records of A to assign each Fi with value xi.

Parameters:

Fi	Field name, which shouldn’t have the same name as any of the original fields in P
xi	Expression, whose results are used as the values of the derived fields
A	A table sequence/record sequence

Options:

@m	Use parallel algorithm to handle data-intensive or computation-intensive tasks to enhance performance; no definite order for the records in the result set.
@i	Won’t generate a record if the result of expression xi is null (this won’t affect a record with null value in the original table sequence)
@x(…;n)	Unfold original fields whose values are records into n levels; default of n is 2

Return value:

A table sequence with added field(s)

Example:

	A
1	=demo.query("select NAME,BIRTHDAY,HIREDATE from EMPLOYEE")
2	=A1.derive(interval@y(BIRTHDAY, HIREDATE):EntryAge, age(HIREDATE):WorkAge)
3	=A1.derive@m(age(HIREDATE):WorkAge)	Use the @m option to increase performance of big data handling.
4	=file("D:\\txt_files\\data1.txt").import@t()	Below is the file data1.txt:
5	=A4.derive@i(SCORE:score_not_null)	If the SCORE value is null, the corresponding record won’t be generated
6	=demo.query("select * from DEPARTMENT")
7	=demo.query("select NAME,GENDER,DEPT,SALARY from EMPLOYEE")
8	>A7.switch(DEPT,A6:DEPT)	Switch values of DEPT of A7’s table over with corresponding records
9	=A7.derive(SALARY*5:BONUS)	Add a new field:BONUS
10	=A7.derive@x(SALARY*5:BONUS)	Use @x option to unfold the DEPT field whose values are records; the default unfolding levels are 2

Note:

The difference between new() and derive(): The new() constructs a new table sequence without changing the original one. By comparison, the derive() copies the original fields and then adds new fields.

P.derive()[331][332]

Description:

Generate a table sequence according to a record sequence.

Syntax:

P.derive()

Note:

The function creates a table sequence by copying the data structure of record sequence P, in order to use the table sequence functions.

Parameters:

P	A record sequence.

Options:

Do not copy the record sequence’s data structure, which will change the record sequence’s structure and which will adjust the number of fields as needed. The option will achieve a better performance as well as an increased risk of error. It’s recommended to be used only when the original record sequence is no longer needed.

Return value:

A table sequence.

Example:

	A
1	*=demo.query("select from SCORES")**
2	=A1.select(SCORE>90)	Return a record sequence.
3	=A2.derive()	Generate a table sequence from the record sequence.
4	=A2.derive@o()	Directly reference the records of the record sequence, instead of generating new ones.

ch.derive()[333][334]

Description:

Add fields to records in a channel.

Syntax:

ch.derive(xi :Fi,…)

Note:

The function adds Fi,… fields to channel ch, making a new channel having “orginal fields of channel ch plus Fi,…”, and then traverse the records of ch to assign xi to each Fi. This is an attached computation.

Parameters:

ch	Channel
Fi	Field name, which shouldn’t be same as one of the existing ones
xi	An expression, whose results will be the values of the new fields

Options:

@i	Won’t generate a corresponding record if there appears null in the results of computing expression x_i;won’t affect the field values of existing fields.

Return value:

Channel

Example:

	A
1	=demo.cursor("select NAME,BIRTHDAY,HIREDATE from Employee")
2	=file("D:\\txt_files\\data1.txt").import@t()	Below is data1.txt：
3	=channel()	Create a channel
4	=channel()	Create a channel
5	=A3.derive(interval@y(BIRTHDAY,HIREDATE):EntryAge, age(HIREDATE):WorkAge)	Add EntryAge field and WorkAge field in A3’s channel
6	=A3.fetch()	Attach ch.fetch() function that gets the final result set to A3’s channel to fetch and store the existing data in the channel
7	=A4.derive@i(SCORE:score_not_null)	Won’t genearate the corresponding record if a SCORE value is null
8	=A4.fetch()	Attach ch.fetch() function that gets the final result set to A4’s channel
9	=A1.push(A3)	Be ready to push A1’s data into A3’s channel, but the action needs to wait
10	=A2.push(A4)	Push data in A2’s sequence into A4’s channel
11	=A1.skip()	Data in A1’s cursor is pushed into the channel and operations are performed as the skip() operation is performed over A1
12	=A3.result()
13	=A4.result()

cs.derive()[335][336]

Description:

Add one or more fields to a cursor.

Syntax:

cs.derive(xi :Fi,…)

Note:

The function adds Fi,… fields to cursor cs, making a new cursor having “orginal fields of channel ch plus Fi,…”, and then traverses each of the records of cs to compute expression xi. It supports multicursors.

Parameters:

cs	Cursor
Fi	Field name. In this case, Fi cannot be of the same name as the existing fields in cs
xi	Expression, whose computed results are the field values

Options:

@i	Won’t generate a record if the result of expression xi is null (this won’t affect a record with null value in the original table sequence)

Return value:

The original cursor cs

Example:

	A
1	=demo.cursor("select NAME,BIRTHDAY,HIREDATE from Employee")
2	=A1.derive(interval@y(BIRTHDAY,HIREDATE):EntryAge, age(HIREDATE):WorkAge)	Add fields EntryAge and WorkAge to the original cursor.
3	=A2.fetch()
4	=file("D:\\txt_files\\data1.txt").cursor@t()	Below is the file data1.txt:
5	=A4.derive@i(SCORE:score_not_null)	If the SCORE value is null, the corresponding record won’t be generated
6	=A5.fetch()

Related functions:

cs.new()

T.derive()^{^[337]}^{^[338]}

Description:

Add a composite table’s fields to a table sequence or a cursor according to the latter’s key values.

Syntax:

T.derive(A/cs,x:C,…;wi,...)

Note:

The function adds one or more fields of composite table T to table sequence A or cursor/multicursor cs according to key values of the latter. It returns a table sequence when adding fields to a table sequence; and returns a cursor when adding fields to an ordinary cursor or a multicursor.

Parameters:

T	A composite table
A/cs	A table sequence/cursor/multicursor
x	Field value
C	Column alias;can be absent
wi	Filtering condition; separate multiple conditions, which should be met at the same time, by comma(s).

Return value:

A table sequence/cursor

Example:

	A
1	=file("D:\\emp10.ctx")
2	=A1.create()	Open a composite table
3	=demo.query("select EID from EMPLOYEE").keys(EID)
4	=A2.derive (A3,NAME,GENDER)	Add fields of the composite table to A3’s table sequence by the latter’s key values
5	=demo.query("select EID from EMPLOYEE").cursor()
6	=A2.derive(A5,NAME:NAME,GENDER:GENDER).fetch()	Add fields of the composite table to A5’s cursor by the latter’s key values
7	=file("D:/employees.ctx").create()	Open a composite table
8	=demo.query("select EID,DEPT from employee").keys(EID)	Return a table sequence with EID as the key
9	=A7.derive(A8,NAME:name,GENDER;GENDER=="M")	Add certain fields of A7’s composite table to A8’s table sequecne according to key values; filtering condition over A7 is GENDER=="M"

T.derive(A/cs,x:C,…;wi,…)^{^[339]}^{^[340]}

Description:

Add fields of a cluster composite table to a table sequence/cursor according to the latter’s key values.

Syntax:

T.derive(A/cs,x:C,…;wi,...)

Note:

Parameters:

T	A composite table
A/cs	A table sequence/cursor/multicursor
x	Field value
C	Column alias
wi	Filtering condition; separate multiple conditions, which should be met at the same time, by comma(s)

Return value:

A table sequence/cursor

Example:

	A
1	=file@0("emp10.ctx",["192.168.0.118:8281"])
2	=A1.create()	Open a composite table
3	=demo.query("select EID from EMPLOYEE").keys(EID)
4	=A2.derive (A3,NAME,GENDER)	Add fields of the cluster composite table to A3’s table sequence by the latter’s key values
5	=demo.query("select EID from EMPLOYEE").cursor()
6	=A2.derive(A5,NAME:NAME,GENDER:GENDER).fetch()	Add fields of the cluster composite table to A5’s table sequence by the latter’s key values

dfx (…)[341][342]

Description:

Through esProc JDBC, search for and execute a program file locally. If not found, then search the server.

Syntax:

dfx (…)

Note:

Pass in the parameter … and call the cellset file dfx waiting to be executed. Firstly, locate the cellset file with relative searching path for execution. If not found, then search the server (The server list is configured in raqsoftConfig.xml file). Once the computation is completed in esProc or server, return a sequence composed of members of the result set; if there are multiple result sets, then return a sequence composed of these result sets. dfx (…) can be regarded as the simple notation of call dfx(…), which is executed with st.executeQuery() and returns a result set.

Parameter:

dfx	Cellset file, with relative addressing path or absolute path
…	Input parameter. Use comma to separate if there are multiple ones. These parameters will be assigned to the parameters specified in the query statement in their order, rather than according to the latter’s names.

Example:

C: \\test.dfx cellset file has the following contents, in which StuId and Class is the cellset parameters.

	A
1	=connect("demo")
2	=A1.query("select * from SCORES where STUDENTID=? and CLASS=?",StuId,Class)
3	=A2.sum(SCORE)
4	>A1.close()
5	return A3

Here’s the test code:

public void testDataServer() {

Connection con = null;

java.sql.PreparedStatement st;

try{

Class.forName("com.esproc.jdbc.InternalDriver");

con= DriverManager.getConnection("jdbc:esproc:local://");

// Call the stored procedure in which test is the name of dfx file

st =con.prepareCall("test ?,?");

// Set the first parameter

st.setObject(1,"4");

// Set the second parameter

st.setObject(2,"Class one");

// Execute stored procedure

st.execute();

// Get result set

ResultSet set = st.getResultSet();

// Print results

printRs(set);

// The following statement gets same result as the above-mentioned calling method has

st =con.prepareCall("test 4,\"Class one\"");

st.execute();

set = st.getResultSet();

printRs(set);

}

catch(Exception e){

System.out.println(e);

}

finally{

// Close the connection

if (con!=null) {

try {

con.close();

}

catch(Exception e) {

System.out.println(e);

}

diff()[343][344]

Here’s how to use diff() function.

A.diff()[345][346]

Description:

Generate a new sequence by removing from the first sub-sequence of a sequence the members that exist in the other sub-sequences of the sequence.

Syntax:

A .diff()

Note:

Generally sequence A contains multiple sub-sequences. The function creates a new sequence by getting the difference of A’s first sub-sequence and the other sub-sequences, ensuring that the new sequence doesn’t include any member of the other sub-sequences.

The algorithm is to compute the difference between the first sub-sequence and the second one, then compute the difference between the result and the third sub-sequence, and so on and so forth.

Parameters:

A	A sequence whose members are sequences

Return value:

A new sequence created by performing difference operations on A’s first sub-sequence and the other sub-sequences.

Example:

	A
1	=[[1,2,3,4,5],[3,7,8]].diff()	[1,2,4,5]
2	=[[1,2,3],[3,2],1].diff()	[]
3	=[[1,2,2,3],2].diff()	[1,2,3] remove only one of the duplicate members
4	=demo.query("select top 2 * from EMPLOYEE")
5	=demo.query("select top 1 * from EMPLOYEE")
6	=[A4,A5].diff()	Since A4 and A5 come from different table sequences and have different store addresses, so the same records are regarded as different members

Note:

If the sub-sequences are record sequences, we can judge if they are duplicate by their store addresses.

Related functions:

A.diff(x)[347][348]

Description:

Generate a sequence by first performing a certain computation on a given sequence and then removing from the resulting sequence’s first sub-sequence the members that exist in the other sub-sequences.

Syntax:

A.diff(x)

Note:

Generally sequence A contains multiple sub-sequences. The function loops through each sub-sequence of A to compute expression x and get the difference of the resulting sequence’s first sub-sequence and the other sub-sequences, ensuring that the difference result doesn’t include any member of the other sub-sequences.

The algorithm is to compute the difference between the first sub-sequence and the second one, then compute the difference between the result and the third sub-sequence, and so on and so forth.

Parameters:

A	A sequence whose members are sequences
x	An expression that returns a sequence

Return value:

A sequence

Example:

	A
1	=demo.query("select * from EMPLOYEE where GENDER = 'M' order by NAME")
2	=demo.query("select * from EMPLOYEE where GENDER = 'F' order by NAME")
3	=[A1,A2].diff(~.(NAME))	Remove only one of the duplicate members

Related functions:

A.diff()

directory()[349][350]

Here’s how to use directory() function.

directory(path)[351][352]

Description:

List the file name(s) satisfying a wildcard path.

Syntax:

directory(path)

Note:

The function lists file name(s) satisfying wildcard path path, excluding the path names.

Parameters:

path

Wildcard path, * represents 0 or multiple characters, and ? represents a single character

Options:

@d	List the subdirectory of path
@p	Return files with full paths under the directory
@m	Create a directory
@r	Delete a directory, which must be empty
@s	Perform recursive query to get all file names under all subdirectories; mutually exclusive with @m and @r
@c	Make case-insensitive; without it the OS will have a say

Return value:

A sequence

Example:

	A
1	=directory("D://*.txt")	Return the txt file list under the root directory on driver D
2	=directory@d("D://tomcat5")	List the subdirectory under the tomcat5 directory
3	=directory@m("D://test")	Create test folder under the root directory on driver D
4	=directory@r("D://test")	Delete D://test directory, but the test folder must be empty
5	=directory@s("D://tomcat5")	Return a list of files in subdirectories under the tomcat5 directory
6	=directory@p("D://tomcat5")	List full path of files under tomcat5 directory

Related functions:

f. exists()

movefile()

dup()^{^[353]}^{^[354]}

Here’s how to use dup() function.

T.dup()^{^[355]}^{^[356]}

Description:

Join up cluster memory table into a local memory table.

Syntax:

T.dup()

Note:

The function joins up cluster memory table T to generate a local memory table.

Parameters:

T A cluster memory table

Return value:

A memory table

Example:

	A
1	=file@n("D:/test0.ctx","169.254.121.62:8281")	Open a duplicate file
2	=A1.create()	Create a duplicate cluster table
3	=A2.attach(table)	Retrieve cluster table table
4	=A3.memory()	Generate a cluster memory table
5	=A4.dup()	Join up the cluster memory table to return a local memory table

T.dup(h)^{^[357]}^{^[358]}

Description:

Copy a local memory table onto nodes to create a duplicate cluster memory table.

Syntax:

T.dup(h)

Note:

The function copies local memory table T onto node or node sequence h to create a duplicate cluster memory table.

Parameters:

T h	A local memory table A node or a node sequence

Return value:

A duplicate cluster memory table

Example:

	A
1	=demo.cursor("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<10")
2	=A1.memory()	Generate a local memory table
3	=A2.dup("169.254.121.62:8281")	Copy the local memory table into a duplicate cluster memory table

elapse()[359][360]

Description:

Get the date/time which is a certain time period before or after a given date/time.

Syntax:

elapse(dateExp, n)

dateExp± n elapse(dateExp, n)

Note:

The function computes the new date which is n days/n months/n years before or after the date dateExp. When getting the same date in last year according to the specified date, if the desired date does not exist, then return the last day of the same month. For example, elapse@m("2009-03-31",-1) returns 2009-02-28.

Parameters:

dateExp	A specified date expression that should return a date or a string of standard date format.
n	An integer expression according to which a date/time n days/years/months/seconds after or before a given date/time is computed, depending on whether n is positive or negative.

Options:

@y	Compute the date which is n years before or after the specified date.
@q	Compute the date which is n quarters before or after the specified date.
@m	Compute the date which is n months before or after the specified date.
@e	If the specified date is the last day of a month, the new date will not be adjusted to the last day of the month to which it belongs. Without the option the new date will be automatically adjusted to the last day of the corresponding month. This option works with @yqm.
@s	Compute the datetime which is n seconds before or after the specified datetime
@ms	Compute the datetime which is n milliseconds before or after the specified datetime; by default the function computes the date which is n days after the specified date.

Return value:

Datetime

Example:

elapse(datetime("19800227","yyyyMMdd"),5)	1980-03-03 00:00:00
elapse@s(datetime("19800227","yyyyMMdd"),5)	1980-02-27 00:00:05
elapse@ms(datetime("19800227","yyyyMMdd"),5)	1980-02-27 00:00:00
elapse(datetime("19800227","yyyyMMdd"),-3)	1980-02-24 00:00:00
elapse@y(datetime("19800227","yyyyMMdd"),-3)	1977-02-27 00:00:00
elapse@q(datetime("19800227","yyyyMMdd"),-3)	1979-05-27 00:00:00
elapse@m(datetime("19800227","yyyyMMdd"),-3)	1979-11-27 00:00:00
elapse@s(datetime("19800227","yyyyMMdd"),-3)	1980-02-26 23:59:57
elapse@ms(datetime("19800227","yyyyMMdd"),-3)	1980-02-26 23:59:59
datetime("19800227","yyyyMMdd")+5	1980-03-03 00:00:00
datetime("19800227","yyyyMMdd")-5	1980-02-22 00:00:00
elapse@y(datetime("19770228","yyyyMMdd"),3)	1980-02-29 00:00:00
elapse@ey(datetime("19770228","yyyyMMdd"),3)	1980-02-28 00:00:00
elapse@q(datetime("19800229","yyyyMMdd"),1)	1980-05-31 00:00:00
elapse@eq(datetime("19800229","yyyyMMdd"),1)	1980-05-29 00:00:00
elapse@m(datetime("19800229","yyyyMMdd"),5)	1980-07-31 00:00:00
elapse@em(datetime("19800229","yyyyMMdd"),5)	1980-07-29 00:00:00

end s[361][362]

Description:

Log the error message.

Syntax:

end s

Note:

Execute abnormal termination deliberately, throw and log the error message s; Without s, execute normal termination.

Parameters:

s	Error message

Example:

	A	B	C
1	[12,23,45,1,11,21]	=[]		B1 is [12,23,45]
2	for A1
3		if A2>10
4			>B1=B1\|A2
5		Else
6			end "small"	Prompt and log an error message "error small" if value in A1 is not greater than 10. Terminate the program normally if no "small" is detected.

enum()[363][364]

Here’s how to use enum() function.

P.enum()[365][366]

Description:

Generate a new record sequence by performing enumeration grouping on an record sequence according to another record sequence.

Syntax:

P.enum(E, y)

Note:

The function generates a new record sequence by grouping the record sequence P according to the record sequence/sequence E.

Parameters:

P	Record sequence to be grouped
E	Record sequence/sequence
y	A field name or an expression in P. y is allowed to be omitted

Options:

@r	Repetitive enum, that is, allocate a certain record of P to multiple groups.
@p	The return value is composed of the sequence numbers of members that exist in P
@n	Group P’s records according to E’s members and return the result groups. In the result set, there is a group to store the unaligned member(s).

Function Keyword:

?	It represents the value of y

Return value:

The new record sequence generated by grouping P

Example:

Ø E is a sequence

	A
1	=["?<=60","?>=60 && ?<=90","?>=90"]	Use y to replace ? in the group condition when computing
2	=demo.query("select * from SCORES")
3	=A2.enum(A1,SCORE)	3 groups in total, and a member will not appear in multiple groups
4	=A2.enum@r(A1,SCORE)	3 groups in total; 60 and 90 are allocated to multiple groups
5	=A2.enum@p(A1,SCORE)	3 groups in total; return the sequence numbers of members that exist in A2 by group
6	=["?<=60","?>=60 && ?<=90"]
7	=A2.enum@n(A6,SCORE)	3 groups in total, group 1 for those not greater than 60, group 2 for those greater than 60 and not greater than 90, and group 3 for the remaining values.

Note:

p.enum() is mainly used to conduct the enum grouping on a single record sequence. The grouping result is a sequence composed of multiple record sets, and each record set is a group. This sequence is in an order exactly equal to that of E. Therefore, you can retrieve the associated group information from E via the sequence numbers. The group result is not a record sequence, so no new data structure will be generated

Related functions:

E.penum()

env()[367][368]

Description:

Assign value to the global variable.

Syntax:

env(v,x)

Note:

The function assigns value x to the global variable v. With x omitted, the global variable will be deleted.

Parameters:

v	The global variable
x	Variable value

Options:

@j	Set the global variable v as a task variable

Return value:

The variable value or null

Example:

	A
1	=env(arg1,12)	12. Assign 12 to the global variable arg1
2	=env(arg1)	Delete the global variable arg1 as the variable value is omitted
3	=env@j(arg2,3)	Set the global variable arg2 as a task variable

eq()[369][370]

Here’s how to use eq() function.

A.eq(B)[371][372]

Description:

Judge if a given sequence can be generated by adjusting the positions of the members of another sequence.

Syntax:

A.eq(B)

Note:

Judge if sequence A can be generated by changing positions of the members of sequence B.

Parameters:

A	A sequence expression
B	A sequence expression

Return value:

Boolean value.

Example:

	A
1	= [1,2,5]	true
2	=[5,2,1]
3	=A1.eq(A2)	true
4	=["a","b","c"]
5	=["b","a","c"]
6	=A4.eq(A5)	true
7	=[5,2,2]
8	=A7.eq(A1)	false

error()[373][374]

Here’s how to use error() function.

db.error()[375][376]

Description:

Obtain the last error information from a database connection.

Syntax:

db.error()

Note:

The function returns the error information corresponding to the previous command related to the database. 0 indicates error free; otherwise, the error code is returned. The error message can only be called one time.

Parameters:

db	Database connection

Options:

@m	Use this option to return information in string.

Example:

	A
1	=file("D://files//student.txt")	Data in the file student.txt is not correct
2	=A1.import@t()
3	=connect@e("demo")	Create a connection and auto-control the commit and rollback operations
4	>A3.execute@k(A2,"update STUDENTS2 set NAME=?,GENDER=?,AGE=? where ID=?",NAME,GENDER,AGE,ID)	The transaction is not committed
5	=A3.error@m()	Return the error message corresponding to sql command execution
6	>file("D:\\log.txt").write@a(A5)	Append error message to the log
7	>A3.close()	Close the connection

Related functions:

eval()[377][378]

Description:

Dynamically parse and compute the expression.

Syntax:

eval(StringExp ,{argExp})

Note:

The function parses the expression string StringExp, evaluate it, and return its result. In the expression string, the value of a keyword ? corresponds to the result of evaluating the expression argExp. If there are more than one ?, then there may be more than one argExp. Generally there is a one-to-one correspondence between argExp and ?.

If the number of ? is more than that of argExp, then the extra ? will get assigned starting from the first argExp again.

You can use a number to specify the corresponding parameter for a ?, as in eval( "?2/?1", 3, 6 ), where the first ? corresponds to the second parameter, and the second ? corresponds to the first parameter. Thus the result is 2.

Parameters:

StringExp	An expression string to be calculated
argExp	Parameter expression

Function keyword:

?	Used in StringExp to represent the value of argExp

Return value:

Result of the specified expression whose data type is determined by the expression itself.

Example:

	A
1	="1+3"
2	=eval(A1)	4
3	=4
4	=eval("?+5",A3)	? is a key word, its value is A3, and the function returns the result of 9
5	=eval("(?+1)/?",3,4)	The first ? is 3, the second ? is 4, and the returned result is 1.0.
6	=eval("(?+?)*?",1,3)	The first ? is 1, the second ? is 3, the third ? is 1 again, the returned result is 4.
7	=eval("?+?",3)	The result is 6 because the number of argExp is less than ?, so argExp will be used repeatedly.
8	=eval("?2/?1",3,6)	The first ? corresponds to the second parameter, the second ? corresponds to the first parameter, so the result is 2.0.

es_close ()[379][380]

Description:

Close REST Client connection.

Syntax:

es_close(fd)

Note:

The function closes connection to REST Client and release resources.

Parameters:

fd	A REST Client object

Example:

	A
1	=es_open("localhost:9200")	Connect to ES server
2	=es_close(A1)	Close the connection

es_delete()[381][382]

Description:

Execute the delete command and return a boolean value.

Syntax:

es_delete(fd, endpoint, entity，header)

Note:

The function executes the delete command and returns true if the deletion action is successful or false if the deletion fails.

Parameters:

fd	A REST Client object
endpoint	Rest API address
entity	A parameter transmitted through http body, which is a JSON string or a block of data in JSON format
header	A variable parameter that passes http header; it is a key type JSON string

Return value

Boolean value

Example:

	A
1	=es_open("localhost:9200","user":"un1234")	Connect to ES server
2	=es_delete(A1,"/accounts/person","user:jacker")	Delete the record where user is jacker under the level where index is accounts and type is person
3	=es_delete(A1,"/student")	Delete the index file where the index is student

es_head()[383][384]

Description:

Execute head command and return a table sequence.

Syntax:

es_head (fd, endpoint)

Note:

The function checks whether a document or a record exists or not. The response value is 200 OK if the document/record exist; otherwise the response value is 404 Not Found.

Parameters:

fd	A REST Client object
endpoint	The address of to-be-checked document/record

Return value:

A table sequence

Example:

	A
1	=es_open("localhost:9200","user":"un1234")	Connect to ES server
2	=es_head(A1,"/accounts/person/1")	Check whether the record where index is accounts, type is person and id is 1 exists or not

es_open()[385][386]

Description:

Connect to Elasticsearch (ES) server in the default http protocol.

Syntax:

es_open(host,..., user:passwd)

Note:

The function connects to the ES server. Parameters user and passwd can be omitted if there are not username and password.

Options:

@s	The https protocol

Parameters:

host	URL of the ES server, the format is: http(s)://hostname:port, in which http(s) can be omitted; the default is http protocol
user	Username for connectiong to an ES server
passwd	Password for connectiong to an ES server

Return value:

A REST Client object

Example:

	A
1	=es_open("localhost:9200”)	Connect to the ES server whose hostname is localhost and port number is 9200 in the http protocol
2	=es_open("http://localhost:9200","user":"un1234")	Connect to the ES server whose hostname is localhost and port number is 9200 in the http protocol; the username is user and password is un1234
3	=es_open@s("https://localhosts:9200","user":"un1234")	Connect to the ES server in https protocol; other parameters are the same as the above

es_get()[387][388]

Description:

Execute the get command and return a table sequence or a cursor.

Syntax:

es_get(fd, endpoint, entity，header)

Note:

The function queries data through a get command and by default returns 10 records at most. There is no restriction about the number of returned records when the function queries a cursor or the ES system. If the JSON data in the result set contains multiple _index, they will be fully displayed. Parameter entity can be omitted.

Options:

@c	Query a cursor and by default return all records
@f	Parameter entity can be a file

Parameters:

fd	A REST Client object
endpoint	Rest API address
entity	A parameter transmitted through http body, which is a JSON string or the name of JSON file
header	A variable parameter that passes http header; it is a key type JSON string

Return value:

A table sequence/cursor

Example:

	A
1	=es_open("localhost:9200","user":"un1234")	Connect to ES server
2	=es_get(A1, "/_cat/health")	Display the health data retrieved from ES server by complete values
3	=es_get(A1, "/_cat/health?v")	Display the health data retrieved from ES server by key values
4	=es_get(A1,"/accounts/person/1")	Query the record where index is accounts, type is person and id is 1
5	=es_get@c(A1,"/accounts/person/_search")	Query records where index is accounts and type is person via the cursor
6	=A5.fetch()	Return records fetched from the cursor
7	=es_get(A1,"/person/_mget","{\"ids\":[\"1\",\"2\",\"5\"]}")	Query in /person the records where ids is 1,2 and 5
8	=es_get@f(A1,"/person/_mget","D:/entity_docs_accounts.txt")	Same as the previous

Note: Here’s the file entity_docs_accounts.txt:

{"ids" : ["1", "2", "5"]}

es_post()[389][390]

Description:

Execute the post command and return a table sequence or a cursor.

Syntax:

es_post(fd, endpoint, entity，header)

Note:

The function queries data through the post command and by default returns 10 records at most. If the JSON data in the result set contains multiple _index, they will be fully displayed. Parameter entity can be omitted.

Options:

@c	Query a cursor
@f	Parameter entity can be a file

Parameters:

fd	A REST Client object
endpoint	Rest API address
entity	A parameter transmitted through http body, which is a JSON string or the name of JSON file
header	A variable parameter that passes http header; it is a key type JSON string

Return value:

A table sequence/cursor

Example:

	A
1	=es_open("localhost:9200 ","user":"un1234")	Connect to the ES server
2	=es_post(A1,"/accounts/_search?q=user:kimchy")	Query in the bank index the record where user is kimchy
3	=es_post(A1,"/_all/_search?q=_id:5")	Query the record where _id is 5 across different databases
4	=es_post@c(A1,"/accounts/person/_search")	Query records where index is accounts and type is person via the cursor
5	=A4.fetch()	Return records fetched from the cursor
6	=es_post@f(A1,"/bank/person/_search","D:/entity_post_accounts.txt")	Parameter entity is a file, from which the function queries records where _gender=“F” under /bank/person and sort them

Note: Here’s the file entity_post_accounts.txt:
{

"query" : {

"match" : { "gender" : "F" }

"track_scores": true,

"sort" : [

{ "account_number" : {"order" : "desc"} },

{ "firstname" : "desc" },

{ "lastname" : "desc" }

]

}

es_put()[391][392]

Description:

Execute the put command and return a table sequence.

Syntax:

es_put(fd, endpoint, entity，header)

Note:

The function executes the put command. Parameter header can be omitted; the REST API address can reach the index, the type or the record.

Options:

@f	Parameter entity can be a file

Parameters:

fd	A REST Client object
endpoint	Rest API address
entity	A parameter transmitted through http body, which is a JSON string or the name of JSON file
header	A variable parameter that passes http header; it is a key type JSON string

Return value:

A table sequence

Example:

	A
1	=es_open("localhost:9200","user":"un1234")	Connect to the ES server
2	=es_put@f(A1, "/shirts", "D: /put_index.txt")	Create an index for records under the shirts index
3	=es_put@f(A1, "/shirts/doc/2", "D:/put_index_record.txt")	Insert a record whose id is 2 under doc type in the newly-created shirts index

Note: Here’s the file put_ index.txt:

{

"mappings": {

"_doc": {

"properties": {

"brand": { "type": "keyword"},

"color": { "type": "keyword"},

"model": { "type": "keyword"}

}

The file put_shirt_ record.txt:

{

"brand": "coop",

"color": "blue",

"model": "girl"

}

execute()[393][394]

Here’s how to use execute() function.

db.execute()[395][396]

Description:

Execute a SQL statement through a specified database connection.

Syntax:

db.execute(sql {,args …} )	Execute the SQL statement sql in database db. args,… is the parameter of sql, which can also be a sequence consisting of parameter values
db.execute(A, sql {, args,…} )	Execute the SQL statement sql in database db over sequence A. args,… is the parameter of sql. Executions of SQL statements will be committed in BATCHSQL mode, which reduces the frequency of database access. Here args shouldn’t be a a sequence type parameter.
db.execute(cs, sql {, args,…} )	Execute the SQL statement sql in database db over cursor cs. args,… is the parameter of sql. Executions of SQL statements will be committed in BATCHSQL mode, which reduces the frequency of database access. Here args shouldn’t be a a sequence type parameter.

Note:

The function executes a SQL statement sql through the specified database connection. It is generally used to execute the SQL statements that change the records in a database (such as update and insert).

Parameters:

db	Database connection object
sql	A SQL statement in the form of select * from table, for example.
args	An argument value passed into the specified SQL command sql. It can be a constant or an expression. The comma is used to separate multiple arguments.
A	A sequence. the SQL statement is executed on each member of A. Generally args is computed against each member of A and the value is passed to the SQL statement for execution.
cs	A cursor

Options:

@k	After the execution is completed, the transaction won't be committed. by default the transaction will be committed.
@s	No preparation will be done for transaction processing.

Example:

	A
1	=demo.execute("insert into DEPARTMENT (DEPT, MANAGER)values(?,?)","TecSupport",5)	Insert a record into the table
2	=demo.execute("delete from DEPARTMENT where DEPT='TecSupport'")	Delete the records whose DEPT values are ''TecSupport''
3	=demo.execute("update DEPARTMENT set MANAGER = ? where DEPT='Sales'","7")	Modify the MANAGER value of the record whose DEPT value is 'Sales' into 7
4	=[["'TecSupport ",5],[" AppSupport",9]].new(~(1):Dept,~(2): Manager)
5	=demo.execute(A4,"insert into DEPARTMENT (DEPT, MANAGER) values (?,?)", #1,#2)	#1 and #2 stand for the first and second columns respectively in A4
6	=demo.query("select * from DEPARTMENT")
7	=file("D://data_dept.txt").cursor@t()	Below is data_dept.txt:
8	=demo.execute(A7,"insert into DEPARTMENT (DEPT, MANAGER)values (?,?)", #1,#2)	A7 is a cursor
9	=demo.execute("insert into DEPARTMENT(DEPT, MANAGER) values(?)",["TecSupport",9])	a args is a sequence of parameter values. It is automatically converted into =demo.execute("insert into DEPARTMENT(DEPT, MANAGER) values(?,?)","TecSupport",9) before execution. Same result as A1’s.

Related functions:

db.query()

db.proc()

exists()[397][398]

Here’s how to use exists() function.

f.exists()[399][400]

Description:

Check if a file exists.

Syntax:

f.exists()

Note:

The function checks if file f exists; return true if it exists, and false if it doesn’t exist.

Parameter:

A file

Return value:

Boolean

Example:

	A
1	=file("D://p1.dfx").exists()	Return true if the file exists

Related functions:

f. date()

movefile()

exp()[401][402]

Description:

Compute e to the n^th power.

Syntax:

exp(n)

Note:

The function computes eⁿ.

Parameters:

n	The exponent

Return value:

Numeric

Example:

	A
1	=exp(4.3)	73.69979369959579

Related functions:

power(x,n)

export()[403][404]

Here’s how to use export() function.

A.export()[405][406]

Description:

Convert a sequence into a string.

Syntax:

A.export(x:F,…;s)

Note:

The function separates each selected fields x of records in table sequence/record sequence/sequence A with the user-defined separator and returns the result as a string. The name of the resulting field in the string is F. If x isn’t specified, then export all fields. Return a one-field string without a field name if A is a sequence. A serial byte value is stored as an integer.

If parameters x:F are absent and if A is a sequence of record, then these records should be of same structure.

Parameters:

A	A table sequence/record sequence/sequence to be exported.
x	Fields to be exported. If omitted, then export all fields of A.
F	Name of the resulting field in the string. If omitted, then use the original field name.
s	User-defined field separator. The default is tab.

Options:

@t	The column names will be written to the string as the first record.
@c	Use comma as the separator when the parameter s is absent, but the user-defined separator s should take priority when there are both s and @c option.
@j	Export as json string, with s being ignored.
@w	Use Windows-style \r\n line break; by default the line break is specified by the operating system.
@x	Export as XML string, with s being the starting point which can’t be omitted; the slash / is used to separate multiple levels of data. <xml> <table> <row> <F>v</F> … </row> … </table> </xml>
@q	Enclose the exported text field values and headers with quotation marks
@o	Use quotation marks as the escape character; need to work with @q. Without it the escape character is the Java-style backslash (\)

Return value:

String.

Example:

	A
1	=demo.query("select EID,NAME from EMPLOYEE")
2	=A1.export()	Parameters x, F, and s are omitted.
3	=A1.export(;"\|")	Specify the separator as "\|".
4	=A1.export@t(EID:id,NAME:name;",")	Specify to-be-exported fields and the separator; make column names the first record and write it at the beginning of the exported string
5	=A1.export@x(NAME;"employee/name")	Convert the table sequence into an XML string, where employee and name are respectively the first level and second level nodes
6	=A1.export@j()	Convert the table sequence into a JSON string and return it
7	[1,23,34,45]	A sequence
8	=A7.export()
9	=A1.export@c()	With @c option, use default separator comma
10	=A1.export@w()	Use Windows-style \r\n line break.
11	=["12\r34","aa\nbb"]
12	=A11.export()
13	=A11.export@q()	With @q option, the exported string is enclosed by double quotations
14	=A11.export@qo()	With @o option, use quotations as the escape character

Note:

Format of the string: Separate the records by space, and the fields by the user-defined separator. The default separator is tab.

Related functions:

f.import()

f.export(A,x:F,…;s)[407][408]

Description:

Write a sequence/table sequence/record sequence into a file.

Syntax:

f.export( A, x:F,…;s)

Note:

The function writes sequence/table sequence/record sequence A into file f in the form of text; it will auto-create an f, which is in the text format by default, if the file doesn’t exist (but the path can’t be auto-created). If A contains a serial byte field, the seirial byte values will be written as in the form of integers.

If A is a table sequence or a record sequence, write all fields into the file if parameter x is absent. If the values of a to-be-exported field are referenced records, just write their primary key values into f. The unexportable fields in A can’t be written into f. A one-field file without field name will be generated if A is a sequence and parameter x is absent.

Parameters:

f	A file
A	The record sequence/sequence to be exported
x	The field to be exported. If omitted, all the fields of A that can be textualized will be exported. The sign # is used to represent a field with a sequence number
F	Resulting field name. If omitted, then use the original field name
s	The user-defined separator used in the text file, and the default separator is tab

Options:

@t	Export the first record to the file as the title
@a	Append. By default, overwrite the original file. The option and @t are mutual exclusive. The appended records and the original records should be of the same structure, otherwise error will be reported
@b	Convert into binary file to speed up the processing; does not support parameter s.
@c	Use comma as the separator when parameter s is absent, but the user-defined separator s should take priority when the parameter is present
@z	Force the execution of @b and write the sequence to the binary file f in segment by segment. The sequence won’t be segmented by default. In this option, parameter s, when present, is a grouping expression by which A is ordered; perform data segmentation only when s is changed. This option is often used to export a large amount of data to a binary file in segments with parallel processing and it can make sure that each segment will be wholly exported
@w	Use Windows-style \r\n line break; by default the line break is specified by the operating system
@q	Enclose the exported text field values and headers with quotation marks
@o	Use quotation marks as the escape character; need to work with @q. Without it the escape character is the Java-style slash (\)

Example:

Write a record sequence into a txt file.

	A
1	=demo.query("select * from DEPARTMENT ")
2	=file("D:\\Department.txt").export(A1)
3	=file("D:\\Department.txt").export@t(A1)
4	=file("D:\\Department2.txt").export(A1;"\|")
5	=file("D:\\Department2.txt").export(A1;)
6	=file("D:\\Department2.txt").export@a(A1)		Still the above example, append the contents from A1 to the contents of the file
7	=file("D:\\Department3.txt").export@b(A1)		Export the file content in binary format
8	=file("D:\\Department4.txt").export@t(A1,DEPT:Dept1;"\|")		If not omitting x, then only export the specified field
9	[a,s,d,f]
10	=file("D:\\myfile.txt").export(A9)		myfile.txt is a one-field file without a field name
11	=file("D:\\Department6.txt").export@c(A1)
12	=demo.query("select * from EMPLOYEE order by GENDER")		Sort by GENDER
13	=file("D:\\EMPLOYEE.btx").export@z(A12,EID,NAME,SURNAME,GENDER,SALARY;GENDER)		Group the file by GENDER and export it to EMPLOYEE.btx
14	=file("D:\\EMPLOYEE.txt").export@w(A1)	Use Windows-style \r\n line break
15	=demo.query("select * from DEPARTMENT").keys(MANAGER)
16	=A12.switch(DEPT,A15:DEPT)
17	=file("D:\\EMPLOYEE1.txt").export@t(A16)	Values of DEPT field in A16 are referenced records; in this case the primary key of the table sequence need to be exported
18	=demo.query("select * from DEPARTMENT")
19	=file("D:\\Department7.txt").export(A18,#1)	#1 represents the first column, so only that column of data is exported
20	=file("D:\\Dep1.txt").export@q(A18,#1)
21	=["12\r34","aa\nbb"]
22	=file("D:\\T1.txt").export@q(A21)
23	=file("D:\\T2.txt").export@qo(A21)

Note:

Format of text file: Separate records by carriage return, and fields by the user-defined separator. The default separator is tab. Here records of table sequence/record sequence/sequence A must be of the same data structure.

Related functions:

f.import()

f.export(cs,x:F,…;s)[409][410]

Description:

Retrieve data from a cursor and write it to a text file.

Syntax:

f.export(cs,x:F,…;s)

Note:

The function writes data of cursor cs to the file object f as text. If the file does not exist, create it automatically (Note that the directory path cannot be created automatically).

Option:

@t	Export the first record to the file as the title.
@a	Append. If omitted, then overwrite the original file. The option and @t are mutual exclusive. f and cs must be of the same structure, otherwise error will be reported.
@b	Convert into binary file to speed up the processing. It ignores @t and does not support the parameter s.
@c	Use comma as the separator when the parameter s is absent, but the user-defined separator s should take priority when there are both s and @c option.
@z	Force the execution of @b and write the sequence to the binary file f in segment by segment. The sequence won’t be segmented without this option. With this option, the parameter s is the grouping expression ruling that sequence A is ordered by s, if the parameter exists, and perform the segmentation only when s changes. The binary file is used to export a large sequenece in segments with parallel processing, which will make sure records in each segment won’t be split.
@w	Use Windows-style \r\n line break; by default the line break is specified by the operating system.
@q	Enclose the exported text field values and headers with quotation marks
@o	Use quotation marks as the escape character; need to work with @q. Without it the escape character is the Java-style slash (\)

Parameters:

f	File object.
cs	Cursor whose data to be exported.
x	Fields to be exported. If omitted, then export all fields in the record sequence A that can be textualized. The sign # is used to represent a field with a sequence number.
F	Resulting field name. If omitted, then use the original field name.
s	User-defined separator; the default is tab.

Example:

Write the cursor data to the text file.

	A
1	*=demo.cursor("select from DEPARTMENT")**
2	=file("D:\\Department1.txt").export(A1)	Tab separator.
3	*=demo.cursor("select from DEPARTMENT")**
4	=file("D:\\Department2.txt").export(A3;"/")	Specify the separator “/”.
5	*=demo.cursor("select from DEPARTMENT")**
6	=file("D:\\Department3.txt").export@t(A5)	Write data to the file with the first record being the title.
7	*=demo.cursor("select from DEPARTMENT")**
8	=file("D:\\Department4.txt").export@t(A7,DEPT:Dept1,DEPT:Dept2;"\|")	If x is not omitted, then export the specified fields.
9	*=demo.cursor("select from DEPARTMENT")**
10	=file("D:\\Department5.txt").export@t(A9,DEPT,MANAGER;"/")	If F is omitted, then use the original field names.
11	*=demo.cursor("select from DEPARTMENT")**
12	=file("D:\\Department5.txt").export@a(A11 DEPT,MANAGER;"/")	Still the above examlple, append the contents of A12 to the contents of Department5.txt.
13	*=demo.cursor("select from DEPARTMENT")**
14	=file("D:\\Department6.txt").export@b(A13)	Export data as the binary file to get a higher speed.
15	=demo.cursor("select * from DEPARTMENT")
16	=file("D:\\Departmen7.txt").export@c(A15)	Use comma as the separator
17	=demo.cursor("select * from EMPLOYEE order by GENDER")	Sort by GENDER.
18	=file("D:\\EMPLOYEE1.btx").export@z(A17,EID,NAME,SURNAME,GENDER,SALARY;GENDER)	Export a segmented binary file grouped by GENDER to EMPLOYEE.btx
19	=demo.cursor("select * from EMPLOYEE order by GENDER")
20	=file("D:\\EMPLOYEE2.txt").export@w(A19)	Use Windows-style \r\n line break.
21	=demo.cursor("select * from DEPARTMENT")
22	=file("D:\\Department8.txt").export(A21,#1)	#1 represents the first column, so only that column in the cursor is exported
23	=file("D:\\Dep1.txt").export@q(A21)	Both exported field values and headers in the text file are quoted
24	=["12\r34","aa\nbb"].cursor()	Above is the content of the cursor
25	=file("D:\\Dep2.txt").export@q(A24)
26	=file("D:\\Dep3.txt").export@qo(A24)	Use double quotations as the escape character

Related functions:

f@o(…)[411][412]

Description:

Syntax of complex functions.

Syntax:

f@o(…) With different function options, a function can implement different functions. The basic format of function options is f@o(…), in which "o" is the option of function f.

Parameters:

f	Function name.
@o	Function option. Different options support different functions, and a same option has similar meaning in different functions.
(...)	The input parameters of a function. The separator of parameters can be colon ":", comma ",", and semicolon ";" and their priorities decrease from left to right just as the order of introducing them.

Faccrint()[413][414]

Description:

The function equals the Excel ACCRINT function.

Syntax:

Faccrint(first_interest,settlement,issue;rate,par)

Note:

The function returns the accrued interest for a security that pays periodic interest. Specify the day count basis method US (NASD) 30/360.

Parameters:

first_interest	The security's first interest date
settlement	The security's settlement date, i.e. the date after the issue date by which a buyer must pay for the security
issue	The issue date of the security
rate	The security's annual coupon rate
par	The security's par value. If omitted, it takes the default value of zero for ￥100

Options：

@2	Semi-annually. It corresponds to the Excel frequency parameter.
@4	Quaterly. It corresponds to the Excel frequency parameter.
@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Faccrint@2(date("2000-10-1"),date("2000-6-1"),date("2000-1-8"):0.1,2000)	79.44444444444444
Faccrint@1(date("2000-10-1"),date("2000-6-1"),date("2000-1-8"):0.1,2000)	108.2089552238806

Faccrintm()[415][416]

Description:

The function equals the Excel ACCRINTM function.

Syntax:

Faccrintm(maturity,issue;rate,par)

Note:

The function returns the accrued interest for a security that pays interest at maturity, with the day count basis method US (NASD) 30/360.

Parameters:

maturity	The security's maturity date
issue	The security'’s issue date
rate	The security's annual coupon rate
par	The security's par value. If omitted, it takes the default value of zero for 100 yuan

Options：

@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Faccrintm@1 (date("2001-6-15"),date("2001-4-1"):0.1,1000)

20.54794520547945

fact()[417][418]

Description:

Compute the factorial of the parameter.

Syntax:

fact(nExp)

Note:

The function computes the factorial of nExp.

Parameters:

nExp	Data for which you want to compute the factorial

Return value:

Long integer (64 bit)

Example:

fact(10)

3628800

false[419][420]

Description:

False value – a logical constant.

Syntax:

false

Note:

It can be used directly in the constant cell or expression.

Example:

	A	B
1	=null		Assign null to A1
2	=A1==null		Judge if A1 is null
3	if A2==false	>a=4	If A2 is false, assign 4 to a
4	else	>a=3	Otherwise assign 3 to a

Related functions:

true

null

Fcoupcd()[421][422]

Description:

The function equals the Excel COUPNCD or COUPNND function.

Syntax:

Fcoupcd(settlement,maturity)	It is equivalent to Excel COUPNCD function and returns the next coupon date after the settlement date for a security. Annually. The day count basis method is US (NASD) 30/360.
Fcoupcd@p(settlement,maturity)	It is equivalent to Excel COUPNND function and returns the previous coupon date before the settlement date for a security. Annually. The day count basis method is US (NASD) 30/360.

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date

Options：

@2	Semi-annually. It corresponds to the Excel frequency parameter.
@4	Quaterly. It corresponds to the Excel frequency parameter.
@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fcoupcd@21(date("2007-1-25"),date("2008-11-15"))	2007-05-15
Fcoupcd@p2(date("2008-3-15"),date("2008-11-3"))	2007-11-03

Fcoups()[423][424]

Description:

The function equals the Excel COUPNUN, COUPDAYS, COUPDAYBS or COUPDAYSNC function

Syntax:

Fcoups(settlement,maturity)	It is equivalent to Excel COUPNUM function and returns the number of coupons payable between a security’s settlement date and maturity date, rounded up to the nearest whole coupon. Annually. The day count basis method is US (NASD) 30/360.
Fcoups@d(settlement,maturity)	It is equivalent to Excel COUPDAYS function and returns the number of days in a coupon period that contains the settlement date. Annually. The day count basis method is US (NASD) 30/360.
Fcoups@b(settlement,maturity)	It is equivalent to Excel COUPDAYBS function and returns the number of days from the beginning of a coupon's period to the settlement date. Annually. The day count basis method is US (NASD) 30/360.
Fcoups@n(settlement,maturity)	It is equivalent to Excel COUPDAYSNC function and returns the number of days from the settlement date to the next coupon date. Annually. The day count basis method is US (NASD) 30/360.

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date

Options：

@2	Semi-annually. It corresponds to the Excel frequency parameter.
@4	Quaterly. It corresponds to the Excel frequency parameter.
@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fcoups@2(date("2008-3-15"),date("2008-11-3"))	2
Fcoups@d2(date("2008-3-15"),date("2008-11-3"))	180.0
Fcoups@b1(date("2008-3-15"),date("2008-11-3"))	133.0
Fcoups@n(date("2008-3-15"),date("2008-11-3"))	228.0

Fdb()[425][426]

Description:

The function equals the Excel DB function.

Syntax:

Fdb(cost,salvage,life,period,month)

Note:

The function calculates the depreciation of an asset for a specified period, using the fixed-declining balance method.

Parameters:

cost	The initial cost of the asset
salvage	The value of the asset at the end of the depreciation (asset residual value)
life	The number of periods over which the asset is to be depreciated (expected useful life of the asset)
period	The period number for which you want to calculate the depreciation (it must has the same unit with life)
month	The number of the months used in the calculation of the first year of depreciation. If omitted, it takes the value of 12 by default.

Example:

Fdb(500000,100000,3,1,6)

103799.11308935669

Fddb()[427][428]

Description:

The function equals the Excel DDB function.

Syntax:

Fddb(cost,salvage,life,period,factor)

Note:

The function calculates the depreciation of an asset for a specified period, using the double-declining balance method, or some other user-defined method. Parameters should all be positive numbers.

Parameters:

cost	The initial cost of the asset
salvage	The value of the asset at the end of the depreciation (asset residual value)
life	The number of periods over which the asset is to be depreciated (expected useful life of the asset)
period	The period number for which you want to calculate the depreciation (It must has the same unit with life)
factor	The rate of balance declining. If omitted, it takes on the default value of 2 (specifying the double-declining balance method)

Example:

Fddb(100000,10000,3650,1)

54.794520547945204

Fdisc()[429][430]

Description:

The function equals the Excel DISC function.

Syntax:

Fdisc (settlement,maturity;pr,redemption)

Note:

The function calculates the discount rate for a security with the day count basis method US (NASD) 30/360.

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date
pr	The security's price
redemption	The security's redemption value

Options：

@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fdisc@0(date("2001-2-15"),date("2001-6-10"),97.975,100)

0.06339130434782626

Fduration()[431][432]

Description:

The function equals the Excel DURATION function.

Syntax:

Fduration (settlement,maturity;coupon,yld)

Note:

The function returns the modified duration of a security that pays periodic interest with an assumed par value of ￥100. The duration is the weighted average of the present value of the cash flows and is used to measure the sensitivity of the price of the security to the interest rates. Annually. The day count basis method is US (NASD) 30/360.

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date
coupon	The security's annual coupon rate
yld	The security's annual yield

Options：

@2	Semi-annually. It corresponds to the Excel frequency parameter.
@4	Quaterly. It corresponds to the Excel frequency parameter.
@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fduration@21(date("2008-1-1"),date("2016-1-1"),0.08,0.09)

5.993774955545178

fetch()[433][434]

Here’s how to use fetch() function.

cs.fetch()[435][436]

Description:

Fetch one or more records from a cursor/distributed cursor.

Syntax:

cs.fetch(n;x)

Note:

Using a cursor, the function fetches n records, or fetches records continuously till the value of expression x (Here x doesn’t return a boolean value) changes or becomes true (Here x returns a boolean value), and then returns them as a sequence/record sequence/table sequence or returns null if the cursor has already been fetched out. It is often used to retrieve a large amount of data in batches. When both n and x are omitted, the function returns all records in a cursor and then closes the cursor. Only one of the parameters n and x is valid.

Parameters:

cs	A cursor/distributed cursor
n	An integer
x	Grouping expression, according to which cs is sorted. With x, n will be ignored

Options:

@0	Won’t actually fetched out the selected data from the cursor. The option enables an action functionally equivalent to copying the data; it doesn’t support parameter x.
@x	Close the cursor after data is fetched.
@o	Return a table sequence

Return value:

A sequence/record sequence/table sequence

Example:

	A
1	=demo.cursor("select * from EMPLOYEE order by SALARY desc")	Return a cursor of retrieved data sorted by SALARY.
2	=A1.fetch@0(3)	Select top 3 highest-paid employees.
3	=A1.derive(interval@y(BIRTHDAY,HIREDATE):EntryAge, age(HIREDATE):WorkAge)	With @0 option used in A2, A3 fetches data from a complete cursor
4	=A1.fetch()
5	=demo.cursor("select * from EMPLOYEE order by SALARY desc")
6	=A1.fetch(;SALARY)	Stop data retrieval when SALARY change to select a group of highest- and equally-paid employees..
7	=A1.fetch()	Return the remaining records in the cursor.
8	=demo.cursor("select * from EMPLOYEE order by SALARY desc")
9	=A5.fetch@x(3)	Close the cursor after data is fetched.
10	=demo.cursor("select * from EMPLOYEE order by SALARY desc")
11	=A7.fetch(3;SALARY==13000)	Stop data retrieval when the value of the expression is true

	A
1	[192.168.0.110:8281,192.168.18.143:8281]	Nodes
2	=file@0("emp.ctx", A1)	emp.ctx is a distributed file across the nodes; node 192.168.0.110 holds a part where EID is from 1 to 250 and node 192.168.18.143 holds another part where EID is from 251 to 500
3	=A2.create()	Open a distributed composite table
4	=A3.cursor()	Return a distributed cursor
5	=A4.fetch()	Fetch records form the distributed cursor

Related functions:

db.cursor()

cs.skip()

ch.fetch()[437][438]

Description:

Fetch and store the existing data in a channel.

Syntax:

ch.fetch()

Note:

The function fetches and stores the existing data in channel ch. It is a set function.

Parameters:

Channel

Return value:

Channel

Example:

	A
1	*=demo.query("select from SALES")**
2	=channel()	Create a channel
3	=A2.select(ORDERID>100)	Attach ch.select() operation to the channel
4	=A2.fetch()	Attach ch.fetch() function that gets the final result set to A2’s channel to fetch and store the existing data in the channel
5	=A1.push(A2)	Push data in A1’s sequence into the channel
6	=A2.result()	Get the result of performing the operation from the channel

mcs.fetch()[439][440]

Description:

Get records from a multicursor.

Syntax:

mcs.fetch()

Note:

The function gets all records from a multicursor, which is similar to record fetching from an ordinary cursor. The order of the resulting records could be different from their orginal order.

Parameters:

mcs

Multicursor

Return value:

Record sequence

Example:

	A
1	=file("D:/txt_files/orders.txt").cursor@m()	Return a multicursor
2	=A1.fetch()	Fetch records from a multicursor
3	=file("D://tb1.txt").import()	tb1.txt contains 10w rows
4	=A3.cursor()	Generate an ordinary cursor
5	=A4.fetch(15000)	Fetch the first 15000 rows
6	=A3.cursor@m(10)	Generate a multicursor
7	=A6.fetch(15000)	Fetch the first 15000 rows Here the fetched records are different from those in A5. With a multicursor, data is fetched from each cursor and then unioned; while with an ordinary cursor, data is sequentially fetched

field()[441][442]

Here’s how to use field() function.

r.field(F)[443][444]

Description:

Get the value of a specified field in a record.

Syntax:

r.field(F)

Note:

The function gets value of the F^th field in record r, or value of string parameter F. Count backward if F<0. Return null if F exceeds the boundary number of the fields or it does not exist.

Parameters:

r	A record
F	Sequence number of a field, or the string parameter in which a variable can be used to reference the field name.

Return value:

The field value

Example:

	A
1	=demo.query("select * from EMPLOYEE")(1).field(2)	Return the second field value of the first record in table sequence demo.query ("select * from EMPLOYEE")
2	=demo.query("select * from EMPLOYEE")(1).field(-2)	Return the second-to-last field value in the first record of the table sequence demo.query ("select * from EMPLOYEE")
3	=demo.query("select * from EMPLOYEE")(1).field(arg1)	SALARY is the value of variable arg1
4	=demo.query("select * from EMPLOYEE")(1).field(“SALARY”)

Related functions:

A.field(F)

A.field(F,x)

r.field(F,x)

r.field(F,x)[445][446]

Description:

Modify a value of the specified field of a record.

Syntax:

r. field(F,x)

Note:

The function modifies the value of the F^th field of record r, or the value of string parameter F, into x. Count backward if F<0. Do not execute if F exceeds the boundary number of the fields or it does not exist.

Parameters:

r	Record
F	Sequence number of a field, or the string parameter in which a variable can be used to reference the field name.
x	Expression whose computing result is the value of the F^th field, or the value of the string parameter F.

Return value:

None

Example:

	A
1	*=demo.query("select from EMPLOYEE")**
2	=A1(1).field(2,"Admin1")	Change the value of the 2nd field of the record 1 to Admin1
3	=A1(1).field(-1,10000)	Modify the value of record 1’s last field into 10,000
4	>arg1="SURNAME"
5	=A1(1).field(arg1,"Lily")	Modify the value of record 1’s SURNAME field into Lily

Related functions:

A.field(F)

A.field(F,x)

r.field(F)

A.field(F)[447][448]

Description:

Get the values of a specified field of a sequence.

Syntax:

A.field(F)

Note:

The function loops through parameter A to get the value of the F^th field from each record, or the value of every string parameter F, and returns a sequence consisting of these values. Count backward if F<0. Return null if F exceeds the boundary number of the fields or it does not exist.

Parameters:

A	A sequence
F	The sequence number of a field, or the string parameter in which a variable can be used to reference the field name.

Return value:

A sequence

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1.field(2)	Return a sequence composed of values of the second field.
3	=A1.field(-2)	Return a sequence comprising values of the second-to-last field
4	=A1.field("NAME")	Return a sequence composed of values of NAME field
5	>arg1="NAME"
6	=A1.field(arg1)	Same as A4

Related functions:

r.field(F)

r.field(F,x)

A.field(F,x)

A.field(F,x)[449][450]

Description:

Modify the value of a specified field in a sequence.

Syntax:

A. field(F,x)

Note:

The function assigns members of sequence x sequentialy to values of F^th field in sequence A, or values of string parameter F. Count backward if F<0. Do not execute if F exceeds the boundary number of the fields or it does not exist.

Parameters:

A	A sequence
F	Sequence number of a field, or the string parameter in which a variable can be used to reference the field name.
x	A sequence whose length is equal to the number of values in F^th field, or a single value, which can be considered as a sequence in which members have the same value and their number is equal to the number of values in F^th field.

Return value:

None

Example:

	A
1	*=demo.query("select top 3 from EMPLOYEE")**
2	=A1.field(9,8000)	Modify the value of the ninth field; parameter x is a single value, and it will be regarded as the sequence [8000,8000,8000] Here’s A1’s result:
3	=A1.field("SALARY",7000)	Modify all values of SALARY field into 7000
4	>arg1="SALARY"
5	=A1.field(arg1,7000)	Same as A3
6	=A1.field(9,[8000,6500,9000])	Here parameter x is a sequence, and this is A1’s result:

Related functions:

r.field(F)

A.field(F)

r.field(F,x)

file()[451][452]

Here’s how to use file() function.

file(fn:cs)[453][454]

Description:

Open a file with the specified name.

Syntax:

file( fn{:cs})

Note:

The function opens a file named fn.

Parameters:

fn	Name of the file to load. Both the absolute path and the relative path are acceptable. If using the relative path, then it is relative to the main path, which is the one configured on the option menu of esProc, and which by default is the current directory (the directory holding the dfx file )
cs	Character set, which supports jvm's built-in character set and which by default is the default value set by OS

Options:

@s	Search the file names on the non-absolute paths in a specified order: Class path -> Search path-> Main path. The search path is the one configured on the option menu of esProc, and the default main path is the current directory. With this option, the function returns the name of a read-only file.
@t	Generate a temporary file under the directory of fn file. Without the fn file, create the temporary file under a tempory directory (a temporary directory is relative to the main directory set in Tool -> Options -> Environment) in Tool -> Options -> Environment or in a relative path.
@a	Make the write action wait when sharing violation happens

Return value:

A file object.

Example:

file("D:/Area.txt":"UTF-8")	Load the Area.txt file from the directory "D:\"; character set is UTF-8.
file("Area.txt")	Load the Area.txt file under the main path.
file@s("data/ Area.txt")	Search the class path first; if not found, then search throughout the list of search paths; lastly, search the main path if not found in the search paths.
file@t("data/Area.txt")	Create a temporary file under the directory data/

file([fni,…]:cs)[455][456]

Description:

Open a specified filegroup.

Syntax:

file( [fn_i,…]:cs)

Note:

The function opens a filegroup with the specified name fn_i….

Parameters:

fn_i

A to-be-loaded filegroup, which can be specified by an absolute path or a relative path; multiple filegroups are allowed. A relative path is relative to the main directory configured in the Options window; the default main directory is the currently open one (the one holding the corresponding dfx file)

Charaset, which is a default one your JVM is using; use one defined by the OS if the parameter is absent

Return value:

File object

Example:

=file(["D:/tmp2.txt","tmp.txt"]:"UTF-8")	Load the filegroup of tmp2.txt and tmp.txt under D:\ directory; the charaset is UTF-8
=file(["tmp2.txt","tmp.txt"]:"UTF-8")	Load the filegroup of tmp2.txt and tmp.txt under the main directory; the charaset is UTF-8

file(fn,h)[457][458]

Description:

Generate a cluster file from a remote composite table file.

Syntax:

file(fn,h)

Note:

The function accesses a remote composite table file fn through a node/node sequence h and generates a cluster file according to fn. Return a remote file when no option is used and parameter h is the node sequence; in this case, it is equivalent to the file(fn:z,h) function.

Parameters:

fn	A composite table file
h	A node or a node sequence

Options:

@z	Get the fn file from partition 1 on h(1), partition 2 on h(2), and so on according to the node sequence to generate a distributed file
@w	Allow the absence of parameter fn; used to generate a writable distributed file
@n	Get the fn file directly by name, instead of searching partitions; the option generates a duplicate file, but generates a distributed file if @z option is also present
@0	Get the fn file from partition 0 to generate a duplicated file; generate a distributed file if @z option is also present
@t	Can retrieve data from one set of nodes to generate a temporary file; doesn’t support a file group

Return value:

A cluster file

Example:

	A
1	=file@0("emp1.ctx",["192.168.0.116:8281","192.168.0.129:8281"])	Read the composite table file emp1.ctx from partition 0 on the node "192.168.0.116:8281","192.168.0.129:8281" to generate a duplicate cluster file
2	=file@z("emp1.ctx",["192.168.0.116:8281","192.168.0.129:8281"])	Read the composite table file emp1.ctx from partition 1 on node "192.168.0.116:8281" and partition 2 on node "192.168.0.129:8281" to generate a distributed cluster file
3	=file@n("emp1.ctx",["192.168.0.116:8281","192.168.0.129:8281"])	Read the composite table file emp1.ctx from the main directories of nodes "192.168.0.116:8281" and "192.168.0.129:8281" to generate a duplicate cluster file
4	=file@n("D:/file/emp2.ctx", ["192.168.0.116:8281","192.168.0.129:8281"])	Retrieve composite table file D:/file/emp2.ctx from nodes "192.168.0.116:8281" and "192.168.0.129:8281" to generate a duplicate cluster file
5	=file@zw(“emp2.ctx”,[“192.168.0.131:8281”])	Create a writable distributed composite table file emp2.ctx in partition 1 on the node "192.168.0.131"
6	=file@t("emp1.ctx",["192.168.0.116:8281","192.168.0.129:8281"])	Retrieve composite table file emp1.ctx from nodes "192.168.0.116:8281" and "192.168.0.129:8281" to geneate a temporary file

file(fn:z,h)[459][460]

Description:

Open a remote file with a specified name.

Syntax:

file(fn:z,h)

Note:

When parameter h is the sequence of the nodes’ main processes, the function finds file fn, which is read-only, in partition z on a certain node in h. The search will first performed on the local machine, and then on the idle remote machines if fn can’t be found locally. If h is a single value, find fn on h; the remote fn can be written. Find the file under the main directory on the node if parameter z is absent.

Parameters:

Name of the file to be loaded. Both the absolute path and the relative path are acceptable. With a relative path, it is relative to the main path. The main path on the IDE is the one configured on the option menu of esProc, and by default it is the current directory. The main path on a server is the value of mainPath in the configuration file raqsoftConfig.xml; this value shouldn’t be null

Partition name

A sequence of nodes

Options:

@t	Perform read and write operations in the temporary directoy on the target node, with z ignored.

Return value:

File object.

Example:

file("D:\\Scores.txt","192.168.0.20:9282")

Load the file “Scores.txt” from the D:\ of the local machine; character set is UTF-8

file("Scores.txt","192.168.0.20:9282")

Firstly, load the Scores.txt file under the main path of the local machine

file("Scores1.txt":0, “192.168.0.20:9282”)

If Scores1.txt is not found locally, then load the file in partition 0 on server "192.168.0.20:9282"

filename()[461][462]

Description:

Split up the full path and get the file name and extension.

Syntax:

filename(fn)

Note:

The function splits the file name and extension from the full path fn.

Parameter:

fn	The full path with the file name

Options:

@e	Only split the extension part from the full path
@n	Split out the file name without the extension
@d	Split out the directory under which the file is located, inclusive of address string
@p	Add the main path before the file name of the non-absolute path. Return the main path directly if fn is ""

Example:

	A
1	=filename("D://file/test.dfx")	Output “test.dfx”
2	=filename@e("D://file/test.dfx")	Output “dfx”
3	=filename@n("D://file/test.dfx")	Output “test”
4	=filename@d("D://file/test.dfx")	Output “D://file”
5	=filename@p("p2.txt")	Output “D:\Program Files\raqsoft\esProc\demo\p2.txt”
6	=filename@p("")	Output “D:\Program Files\raqsoft\esProc\demo”

Related functions:

file()

fill()[463][464]

Description:

Create a new string by concatenating strings together.

Syntax:

fill(s,n)

Note:

Get a new string by concatenating n strings together

Parameters:

s	Source strings for making up a new string
n	Number of source strings that constitute the new string

Return value:

String

Example:

fill("1 ",10)	"1 1 1 1 1 1 1 1 1 1 "
fill("a b",10)	"a ba ba ba ba ba ba ba ba ba b"

find()[465][466]

Here’s how to use find() function.

A.find()[467][468]

Description:

Find a record according to its primary key value.

Syntax:

A.find(k)

Note:

The function finds records from a record sequence/table sequence whose primary key values are k. Use the index table if there is one.

Parameters:

A	A record sequence/table sequence
k	Primary key, which will be written as a sequence if it is a multi-field primary key.

Options:

@b	Enable the binary search. Here, A must be ordered by the primary key; otherwise, the result will be wrong. The index table will be ignored.
@k	Return members of A matching the sequence of key values specified by parameter k

Return value:

Records

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1.keys(NAME,DEPT)
3	=A1.find(["Alexis","Sales"])	A sequence is used since the key contains two fields
4	=demo.query("select * from EMPLOYEE")	This table sequence is ordered by the EID field
5	=A4.keys(EID)
6	=A4.find@b(3)	@b is used to enable the binary search in order to speed up the computation
7	=A4.find@k(2,15,69,220)	With @k option, the function returns members matching the specified key values

Related functions:

A.pfind()

T.find(k,…)[469][470]

Description:

Find the record(s) according to the specified primary key value(s) from a memory table.

Syntax:

T.find(k,…)

Note:

The function finds records where the primary key value is k from memory table T.Use binary search if there isn’t an index.

Parameters:

T	A memory table
k	The primary key; write multiple keys as a sequence

Options:

@k	Find multiple records according to multiple primay keys and return them as a record sequence; write multiple primary keys in the format of [[k1,k2],[...],...]

Return value:

A record/record sequence

Example:

	A
1	=demo.cursor("select EID,NAME,GENDER from employee where EID< 10")	Return a cursor
2	=A1.memory()	Return a memory table
3	=A2.keys(EID,NAME)	Set EID and NAME as the keys of the memory table
4	=A2.find([8,"Megan"])	The two primary keys are written as a sequence
5	=A2.keys(EID,GENDER)	Set EID and GENDER as the keys of the memory table
6	=A2.find@k([[8,"F"],[2,"F"]])	Use @k option to find multiple records
7	=A2.keys(EID)	Set EID as the key of the memory table
8	=A2.find(3)	Find the record where EID is 3

T.find(k;x:C,..)^{^[471]}^{^[472]}

Description:

Find the record(s) according to the specified primary key value(s) from a base table.

Syntax:

T.find(k;x:C,..)

Note:

The function finds the record(s) where key value(s) is k and returns a record/record sequence containing one field C. The key value k can be represented by the first dimension value which can uniquely identify a record.

Parameters:

T	Base table
k	The primary key; write multiple keys as a sequence
x	Column name; retrieve all field if omitted
C	Column alias; can be omitted

Options:

@k	Find multiple records according to multiple primay keys and return them as a record sequence; write multiple primary keys in the format of [[k1,k2],[...],...]

Return value:

A record/record sequence

Example:

	A
1	=file("E:/find1.ctx")	Return a cursor
2	=A1.create()	Open a composite table’s base table whose dimensions are EID and NAME
3	=A2.find([8,"Megan"])	Since parameter x is absent, the function returns all columns
4	=A2.find([8,"Megan"];EID,SALARY)	Return specified columns
5	=A2.find@k([[4,"Emily"], [8,"Megan"]];EID,SALARY)	Find multiple records with @k option

Fintrate()[473][474]

Description:

The function equals the Excel INTRATE function.

Syntax:

Fintrate (settlement,maturity;investment,redemption)

Note:

The function returns the interest rate for a security that pays interest at maturity, with the day count basis method as US (NASD) 30/360.

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date
investment	The initial amount invested into the security
redemption	The security's redemption value

Options：

@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fintrate@0(date("2001-2-15"),date("2001-5-15");1000000,1014420)

0.058328089887640454

Firr()[475][476]

Description：

The function equals the Excel IRR function.

Syntax：

Firr(values,guess)

Note：

The function calculates the internal rate of return for a series of cash flows represented by numeric values. The internal rate of return is the rate that makes the net present value from a particular investment equal to zero, that is, the current value of the returns received from the investment happens to be equal to the the investment cost.

Parameters：

values	A sequence containing the values of a series of cash flows used to calculate the internal rate of return. It must contain at least one periodic payment (negative value) and at least one periodic income (positive value).
guess	An estimated value for IRR function’s calculation. If omitted, it will take on the default value of 0.1

Example：

Firr([-70000,12000,15000,18000,21000])	-0.02124484827331908
Firr([-70000,12000,15000,18000,21000,26000])	0.08663094803666999
Firr([-70000,12000,15000,18000,21000,26000],-0.1)	0.08663094803655035

float()[477][478]

Description:

Convert a string or a number into a 64-bit double-precision floating-point number.

Syntax:

float(stringExp)

float(numberExp)

Note:

stringExp should be a string that consists of a number which has 64 bits or less than. For a value of more than 64 bits, the result of float(stringExp) is imprecise.

numberExp should be a numeric value which has 64 bits or less. For a value of more than 64 bits, the result of float(numberExp) is imprecise.

Parameters:

stringExp	The string expression you want to convert as a double-precision floating-point number.
numberExp	The number you want to convert as a double-precision floating-point number.

Return value:

A 64-bit double-precision floating-point number

Example:

float("1234567")	1234567.0
float(1234567)	1234567.0

Related functions:

decimal()

int()

long()

number()

string()

floor()[479][480]

Description:

Truncate data at the specified position and reject all the remaining part if any.

Syntax:

floor(numberExp, {nExp})

Note:

The function truncates data numberExp at the specified position nExp and rejects all the remaining part if any.

Parameters:

numberExp

Data to be truncated

nExp

An integer to specify the position from which data is to be truncated; taken as 0 when it is omitted

>0: Move the decimal point to the right for nExp places

<0: Move the decimal point to the left for nExp places

=0: Indicate the current decimal place.

Return value:

Numeric type

Example:

floor(3451231.234,0)	3451231.0
floor(3451231.234,-1)	3451230.0
floor(3451231.234,-2)	3451200.0
floor(3451231.234,1)	3451231.2
floor(3451231.234,2)	3451231.23

Related functions:

ceil()

round()

Fmirr()[481][482]

Description:

The function equals the Excel MIRR function.

Syntax:

Fmirr(values,finance_rate,reinvest_rate)

Note:

The function returns the modified internal rate of return for a series of periodic cash flows, taking into consideration the cost of the investment and the interest on the reinvestment of cash.

Parameters:

values	A sequence containing the values of payment (negative value) and income (positive value) at each of the regular periods . At least one negative value and at least one positive value must be contained.
finance_rate	The interest rate paid on the money invested.
reinvest_rate	The interest rate paid on the reinvested cash which is the net income from the regular periods.

Example:

Fmirr([-120000,39000,30000,21000,37000,46000],0.1,0.12)

0.1260941303659051

fname()[483][484]

Here’s how to use fname() function.

T.fname(i)[485][486]

Description:

Get the names of fields of the table sequence according to the serial numbers of these fields.

Syntax:

T. fname(i)

Note:

The function gets the name of the field whose serial number is i from table sequence T. Return all field names in T If no parameter is present.

Parameters:

T	Table sequence
i	Serial number of a field.

Return value:

A string or a sequence

Example:

	A
1	=demo. query("select * from EMPLOYEE")
2	=A1.fname(2)	“NAME”, the name of the 2nd field is NAME.
3	=A1.fname()	Return a sequence comprising all field names in A1.

Related functions:

r.fname()

r.fname(i)[487][488]

Description:

Get the field names from records according to the serial numbers of these fields.

Syntax:

r. fname(i)

Note:

The function gets the name of the field whose serial number is i from record r. If no parameter is present, then return all field names in r.

Parameters:

r	Record
i	Serial number of a field

Return value:

Character strings or sequences

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1(1).fname(2)	“NAME”, the name of the 2nd field in the first record is NAME..
3	=A1(1).fname()	Return a sequence comprising all field names of the 1st record in A1

Related functions:

T.fname()

fno()[489][490]

Here’s how to use fno() function.

T.fno(F)[491][492]

Description:

Get the serial number of a field in a table sequence.

Syntax:

T.fno(F)

Note:

The function gets the serial number of field F in T. If there is no parameter, the number of fields in T will be returned; if the specified field cannot be found, a null value will be returned.

Parameters:

T	Table sequence
F	Field name

Return value:

The serial number of field F in T

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1.fno(EID)	1, which indicates that the serial number of field "EID" is 1
3	=A1.fno()	9, which indicates that there are 9 fields in the table sequence

Related functions:

r.fno()

r.fno(F)[493][494]

Description:

Get the serial number of a field of a record in a table sequence.

Syntax:

r.fno(F)

Note:

The function gets the serial number of field F of record r in the table sequence; if there is no parameter, return the number of fields in the table sequence in which r locates. If the field cannot be found, a null value will be returned.

Parameters:

r	A record
F	Field name

Return value:

The serial number of a field

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1(2).fno(EID)	1, which indicates that the serial number of the field "EID" is 1
3	=A1(2).fno()	9, which indicates that there are 9 fields in the table "Employee"

Related functions:

T.fno()

Fnper()[495][496]

Description:

The function equals the Excel NPER function.

Syntax:

Fnper(rate,pmt,pv,fv)

Note:

The function returns the number of periods required to pay off a loan according to a specified periodic payment.

Parameters:

rate	The interest rate per period; it is a fixed value.
pmt	The amount paid per period, which keeps unchanged during the whole period of paying off the loan. To omit it, pv must exist.
pv	The present value of the loan, known as the principal.That is the money that already exist when the payment for an investment (or a loan) begins, or the total amount of present values of a series of future payments.
fv	The future value of the loan, or the cash balance you hope to achieve after the final payment. If omitted, its value will be assumed as zero (for example the future value of a loan can be zero).

Options：

@t	Indicating the payment type, it corresponds to Excel type parameter. If using the option, choose type 1; if not, choose type 0.

Example:

Fnper(0.06/12,-1200,150000)

196.65585756847307

Fnpv()[497][498]

Description:

The function equals the Excel NPV function.

Syntax:

Fnpv(rate,values)	Equivalent to Excel NPV function
Fnpv(rate,values,dates)	Equivalent to Excel XNPV function

Note:

The function returns the net present value of an investment, based on the discount rate and a series of future payments (negative value) and income (positive value). The net present value is the difference between the present value of future cash inflows and outflows from an investment and the amount of investment.

Parameters:

rate	The discount rate over one period (which is equal to inflation rate and the rate of competitive investment); it is a fixed value.
values	A sequence of values representing payments and incomes that must occur at regular time interval and at the end of each period.
dates	A sequence of dates corresponding to the array of cash payments. The first date of payment denotes the beginning of the payments for the investment.

Example:

Fnpv(0.11,[-10000,3000,5000,6000])	1034.2010420979072
Fnpv(0.11,[-10000,3000,5000,6000],[date("2008-01-01"),date("2008-05-23"),date("2009-03-10"),date("2009-5-15")])	2497.061973416109

for[499][500]

Here’s how to use for statement.

for a,b,s[501][502]

Description:

Execute a loop according to the specified scope and step.

Syntax:

for a,b,s

Note:

The statement executes the code block in loops from a to b with a step of s.

Parameters:

a	An integer
b	An integer
s	An integer to indicate the step. Its value is 1 by default.

Example:

	A	B
1			Save the cumulative total -18 - in A1.
2	for 1,11,5
3		>A1=A1+A2	Add up integers within the scope from 1 to 11 with a step of 5, i.e. every 4 integers.

for cs,n;x[503][504]

Description:

Loop through a cursor.

Syntax:

for cs,n;x

Note:

The statement retrieves n records from the cursor and returns or retrieves records till x… has changed. Close the cursor once the retrieval is completed. This function is often used to fetch a large volume of records by group. Return all the remaining records and close the cursor when omitting n and x.

Parameters:

cs	Cursor
n	Number of records
x	Grouping expression, and cs is sorted by x. With x, n can be ignored.

Example:

	A	B
1	=demo.cursor("select * from EMPLOYEE order by SALARY desc")	=[]
2	for A1,10;SALARY
3		>B1.insert(0,A2)	Loop through the cursor, selecting records with the same SALARY value and inserting them into B1.

for x[505][506]

Description:

Start a loop.

Syntax:

for x

Note:

The statement starts a loop executing the code block.

Parameter:

x	A sequence, an integer, or a logic expression. Loop through the code block against x or to(x), or if x is true. If x is empty, then the loop will be endless.

Example:

x is an integer:

	A	B
1			Save the cumulative total 55 in A1
2	for 10
3		>A1=A1+A2	Add up the integers from 1 to 10

x is empty:

	A	B	C
1	=0			5050
2	for			Loop will be endless if x is empty. When the loop count reaches 100, then break the loop
3		>A1=A1+#A2
4		if #A2==100	break

x is a boolean expression:

	A	B
1	=15
2	for A1>10		If A1 >10, then start a loop through the code block; otherwise, quit the loop
3		>B1=B1+#A2
4		>A1=A1-1

x is a sequence:

	A	B
1	=demo.query("select * from EMPLOYEE")	0	Get the oldest age among all Texas employees in B1 after the loop is over
2	=A1.select(STATE=="Texas")
3	for A2	=age(A3.BIRTHDAY)	A3 performs loop over each Texas employee while computing their age
4		>B1=max(B1,B3)	The oldest age is stored in B1

fork[507][508]

Here’s how to use fork statment.

fork A_i,…[509][510]

Description:

Use multithreads to execute the code block in a cellset.

Syntax:

fork Ai,…

Note:

Ai is a sequence parameter, whose length determines the number of parallel threads. The statement makes multiple duplicates of the current cellset and its context to execute them respectively using multiple threads. A sequence parameter will be separated to have its members respectively used as the value of current cell for the execution of each thread; and a single-value parameter will be duplicated to be distributed to each thread. The result of return statement in the code block will be used in the form of a sequence as the cell value of the main program to call the subroutine.

Parameters:

Ai	A sequence

Example:

1) Single parameter

	A	B
1	fork [[1,20,6,14,5],[32,8]]	//return the result of executing result statement of multithreads
2		=connect("demo")
3		=B2.query("select * from EMPLOYEE where EID in (?) ",A1)
4		=B2.close()
5		return B3

2) Multiple parameters

	A	B
1	fork [[1,20,6,14,5],[32,8]],"F"	//return the results of executing result statement of multithreads
2		=connect("demo")
3		=B2.query("select * from EMPLOYEE where EID in (?) and GENDER=?",A1(1),A1(2))
4		=B2.close()
5		return B3

Related functions:

callx()

call()

fork cs^{^[511]}^{^[512]}

Description:

Perform parallel computation over a multicursor.

Syntax:

fork cs

Note:

The function performs parallel computation over a multicursor. Within a parallel computing code block, the referenced cell represents the current thread of cursor.

Parameters:

cs	A multicursor

Example:

	A	B
1	=file("employee.txt")	=A1.cursor@mt()	Create a multicursor based on employee.txt and return it
2	fork B1		Perform parallel computation over the multicursor
3		=A2.select().fetch()	Get records from each thread of cursor by loop

fork ....;h,s reduce[513][514]

Description:

Execute a code block with multiple threads on multiple nodes.

Syntax:

fork ….;h,s reduce

Note:

…. is a parameter sequence, whose length determines the number of parallel threads. The statement makes multiple duplicates of the current cellset and its context to execute them respectively using multiple threads running on multiple nodes listed in sequence h. A sequence parameter will be separated to have its members respectively used as the value of current cell for the execution of each thread on the nodes; and a single-value parameter will be duplicated to be distributed to each thread. The result of return statement in the code block will be used in the form of a sequence as the cell value of the main program to call the subroutine. Executing a code block with multiple threads on multiple nodes is functionally equivalent to callx() function without deploying a dfx file on each node. You can’t reference cells and variables other than the parameters of the fork statement in the code block. A referenced cellset variable (which includes cell names) will also be distributed to the cellset on each node.

Parameters:

	….	A parameter sequence, whose members will be distributed among servers; the distribution will stop when the number of subtasks on every server reaches its maximum and will resume as soon as there is an available server. The subtasks on a server will be reassigned if it fails.
	h	The server sequence in which each server is represented by a string in the form of "address:port number", like "192. 168. 0. 86: 4001".
s			A sequence consisting of integer sequences; can be omitted
reduce			The reduce action; ~~ represents the current result of performing reduce and ~ represents the result returned by the current task; can be omitted

Example:

1) Single parameter

	A	B
1	fork [[1,20,6,14,5],[32,8],23];["192.168.1.100:8989","192.168.1.100:8282","192.168.1.100:8283"]	*// return results of executing result* statement of multithreads on multinodes**
2		=connect("demo")
3		*=B2.query("select from EMPLOYEE where EID in (?) ",A1)**
4		=B2.close()
5		return B3

	A	B
1	[192.168.0.116:8281,192.168.0.129:8281]
2	[English,Math,PE]
3	[[1],[2,3]]
4	fork A2;A1,A3
5		=connect("demo")
6		=B5.query("select * from SCORES where SUBJECT=?",A4)
7	reduce	~~\|~

2) Multiple parameters

	A	B
1	fork [[1,20,6,14,5],[32,8],[3,4],23,12,89,56,90,231,333,111,231],"F";["192 .168.1.100:8989","192.168.1.100:8282","192.168.1.100:8283"]	*// return results of executing result* statement of multithreads on multinodes**
2		=connect("demo")
3		*=B2.query("select from EMPLOYEE where EID in (?) and GENDER=?",A1(1),A1(2))**
4		=B2.close()
5		return B3

Related functions:

callx()

fork Ai,...

fork … fork …^{^[515]}^{^[516]}

Description:

Execute multiple code blocks in parallel.

Syntax:

fork

…

fork

…

Note:

The function executes multiple code blocks in parallel and assigns the result of executing each code block to the corresponding fork cell.

Example:

	A	B
1	fork [[1,20,6,14,5],[32,8]]	//fork
2		=connect("demo")
3		*=B2.query("select from EMPLOYEE where EID in (?) ",A1)**
4	fork [[1,20,6,14,5],[32,8]],"F"	//fork
5		=connect("demo")
6		*=B5.query("select from EMPLOYEE where EID in (?) and GENDER=?",A4(1),A4(2))**

format()^{^[517]}^{^[518]}

Description:

Generate a formatted string in Java.

Syntax:

format (s,…)

Note:

The function converts data of any type into a formatted string in Java; parameter … is the parameter of string s.

Parameters:

s	A string
…	The format parameter of the specified string

Example:

format("my name is %s","wind")	my name is wind
format("this is %f",9552.21)	this is 9552.210000
format("this is %d",-2)	this is -2

Return value:

A string

Format specifiers in Java:

Format Specifier	Conversion Applied
%s	String
%c	Character
%b	Boolean
%d	Decimal integer
%x	Integer hexadecimal
%o	Octal integer
%f	Decimal floating-point
%a	Floating-point hexadecimal
%e	Scientific notation
%g	Causes Formatter to use either %f or %e, whichever is shorter
%h	Hash code
%%	Inserts a percent sign
%n	Inserts a newline character
%tx	Datetime (x is a suffix to describe the portion and precise format of the time or date desired)

Fpmt()[519][520]

Description:

The function equals the Excel PMT function.

Syntax:

Fpmt(rate,nper,pv,fv)

Note:

The function calculates each period’s amount required to pay off an investment loan, based on a constant interest rate and the constant periodic payments.

Parameters:

rate	The interest rate per period; it is a fixed value
nper	The number of periods over which the investment (or loan) requires or is to be paid
pv	The present value of the loan /investment, known as the principal. That is the money that already exist when the payment for an investment (or a loan) begins, or the total amount of present values of a series of future payments
fv	The future value of the loan/investment, or the cash balance you hope to achieve after the final payment. If omitted, its value will be assumed as zero (for example the future value of a loan can be zero)
per	The number of period in which the principal appears. Its value must between 1 and nper

Options:

@t	Indicating the payment type, it corresponds to Excel type parameter. If using the option, choose type 1; if not, choose type 0.
@i(rate,nper:per,pv,fv)	This option makes the function equivalent to Excel IPMT function and calculates the interest payment for a given period, with constant periodic payment and a constant interest rate
@p(rate,nper:per,pv,fv)	This option makes the function equivalent to Excel PPMT function and calculates the principal amount during a specific period of an investment or loan that is paid in constant periodic payments, with a constant interest rate

Example:

Fpmt@t(0.07/12, 10, 200000)	-20647.264618755307
Fpmt@i(0.1/12,36:1, 8000)	-66.66666666666666
*Fpmt@p(0.07/12,1210:1,120000)**	-693.3017506234848

Fprice()[521][522]

Description:

The function equals the Excel PRICE, PRICEDISC or PRICEMAT function.

Syntax:

Fprice(settlement,maturity;rate,yld,redemption)	Equivalent to Excel PRICE function. It calculates the price per ¥100 par value of a security that pays periodic interest. Annually. Specify the day count basis method US (NASD) 30/360.
Fprice@d(settlement,maturity;discount,0,redemption)	Equivalent to Excel PRICEDISC function. It calculates the price per ¥100 par value of a discounted security. Specify the day count basis method US (NASD) 30/360.
Fprice@m(settlement,maturity,issue;rate,yld)	Equivalent to Excel PRICEMAT function. It calculates the price per ¥100 par value of a security that pays interest at maturity. Specify the day count basis method US (NASD) 30/360.

Note:

The function returns the price of a security that pays periodic interest, or of a discounted security, or of a security that pays periodic interest

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date
rate	The security's annual coupon rate
yld	The security's annual yield
redemption	The security's redemption value
discount	The security's discount rate
issue	The security’s issue date

Options：

@2	Semi-annually. It corresponds to the Excel frequency parameter.
@4	Quaterly. It corresponds to the Excel frequency parameter.
@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fprice@m(date("2001-2-15"),date("2002-4-13"),date("2000-11-11");0.061,0.061)	99.89464887553818
Fprice@d1(date("2001-2-15"),date("2002-4-13"),0.4,0,0.061)	0.03278958904109588

Frate()[523][524]

Description:

The function equals the Excel RATE function.

Syntax:

Frate(nper,pmt,pv,fv,guess)

Note:

The function calculates the interest rate required to pay an investment, including both the reimbursement rate of the constant periodic payment and the rate of return of the one-off payment.

Parameters:

nper	The number of periods over which the investment or loan is to be paid
pmt	The payment amount per period, including the principal and the interest
pv	The present value of the loan /investment, known as the principal. That is the money that already exist when the payment for an investment (or a loan) begins, or the total amount of present values of a series of future payments
fv	The future value of the loan/investment, or the cash balance you hope to achieve after the final payment. If omitted, it will take on the default value of zero
guess	An estimated interest rate. If omitted, it will take on the assumed value of 10%. Both guess and nper must use the same unit.

Options:

@t	Indicating the payment type, it corresponds to Excel type parameter. If using the option, choose type 1; if not, choose type 0.

Example:

Frate(12*6, -2200, 100000)

0.013798002390137705

Freceived()[525][526]

Description:

The function equals the Excel RECEIVED function.

Syntax:

Freceived(settlement,maturity;inverstment,discount)

Note:

The function returns the amount received at maturity for a security.

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date
investment	The initial amount invested into the security
discount	The security's discount rate

Options：

@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Freceived@0(date("2001-2-15"),date("2001-5-15"),1000000,0.0575)	1014420.2658626447
Freceived@5(date("2001-2-15"),date("2001-5-15"),1000000,0.0575)	1014219.9190013407

Fsln()[527][528]

Description:

The function equals the Excel SLN function.

Syntax:

Fsln(cost,salvage,life)

Note:

The function returns the straight-line depreciation of an asset for each period. The depreciation for each period is the same.

Parameters:

cost	The initial cost of the asset
salvage	The value of the asset at the end of the depreciation (also known as asset residual value)
life	The number of periods over which the asset is to be depreciated (sometimes called expected useful life of the asset)

Example:

Fsln(300000, 20000,8)

35000.0

Fsyd()[529][530]

Description:

The function equals the Excel SYD function.

Syntax:

Fsyd(cost,salvage,life,period)

Note:

The function returns depreciation of an asset for a specified period, using the sum-of-years’ digits method.

Parameters:

cost	The initial cost of the asset
salvage	The value of the asset at the end of the depreciation (also known as asset residual value)
life	The number of periods over which the asset is to be depreciated (sometimes called expected useful life of the asset)
period	The period for which the asset’s depreciation is calculated (it must use the same unit as life)

Example:

Fsyd(500000, 5000,10, 1)

90000.0

ftp_cd()[531][532]

Description:

Set the remote working directory/directories on the FTP server.

Syntax:

ftp_cd(client,remotePath)

Note:

External library function. The parameter remotePath can be omitted when there’s only one remote working directory.

Parameters:

client	An FTP client object
remotePath	The path name of a remote working directory; when it is omitted, the remote working directory on the FTP server is by default regarded as the root directory.

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")
2	=ftp_cd(A1,"/folder1")	Set /folder1 as the remote working directoy
3	=ftp_put(A1,"test.txt","G:/Test.txt")
4	>ftp_close(A1)

Related functions:

ftp_dir()

ftp_client()[533][534]

Description:

Create an FTP client.

Syntax:

ftp_client(server:port,user,pwd)

Note:

External library function. By default the FTP server operates in an active mode.

Options:

@d	Start the FTP passive mode

Parameters:

server	An FTP server’s IP address
port	An FTP server’s port number, which is by default 21 and can be omitted
user	The username to access an FTP server
pwd	The password to access an FTP server

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")	Create an FTP client
2	=ftp_cd(A1,"/workPath")
3	=ftp_put(A1,"test.txt","G:/Test.txt")
4	>ftp_close(A1)

Related functions:

ftp_close()

ftp_close()[535][536]

Description:

Exit an FTP client program.

Syntax:

ftp_close(client)

Note:

This external library function closes an FTP connection.

Parameters:

client

An FTP client object

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")	Create an FTP client
2	=ftp_cd(A1,"/folder1")
3	=ftp_put(A1,"Test1.docx","G:/Test.docx")	Upload a file to the FTP server
4	>ftp_close(A1)	Exit the FTP client program

Related functions:

ftp_client()

ftp_dir()^{^[537]}^{^[538]}

Description:

List all directories and files under the current directory on an FTP server.

Syntax:

ftp_dir(client,multiFiles)

Note:

This is an external library function. When parameter multiFiles is a relative path, it is relative to the current working directory; when it is preceded by a slash sign (/), it is an absolute path.

For a wildcard character, the question mark (?) signifies a single character, an asterisk (*) signifies any character, and double asterisk (**) signifies any character plus a directory.

Options:

@d	Only list directories; parameter multiFiles is a wildcard-specified server file
@p	List full paths of directories and files; parameter multiFiles is a wildcard-specified server file
@m	Create new directories; parameter multiFiles is a file with fixed name
@r	Delete empty directories; parameter multiFiles is a file with fixed name

Parameters:

client	An FTP server client object
multiFiles	Wildcard-specified server files; can be duplicated

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")
2	=ftp_cd(A1,"/ WorkingDirectory ")
3	=ftp_dir@m(A1,"folder1")	Create folder1 directory under the current directory WorkingDirectory
4	=ftp_dir@m(A1,"folder2","/folder3")	Create folder2 directory under the current directory and create folder3 directory under the root directory
5	=ftp_dir@r(A1,"folder1")	Delete the empty directory folder1 from the current working directory
6	*=ftp_dir@d(A1,"folder")**	List directories preceded by ‘folder’ in the current working directory
7	*=ftp_dir@d(A1,"/a/??/")	List directories preceded by a, and files and directories having subdirectores whose names are less than or equal to two characters
8	*=ftp_dir@p(A1,"folder")**	List directories preceded by ‘folder’ in full path under the current directory
9	>ftp_close(A1)

Related functions

ftp_cd()

ftp_get()[539][540]

Description:

Download a file from the FTP server.

Syntax:

ftp_get(client,remoteFile,localFile)

Note:

External library function. If the parameter localFile is a relative path, it is relative to the path to the current dfx file.

Options:

@f	Overwrite the local namesake file

Parameters:

client	An FTP client object
remoteFile	A remote file
localFile	A local file

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")
2	=ftp_cd(A1,"/WorkingDirectory")
3	=ftp_get(A1,"Records.docx","G:/Records_Download.docx")	Download a file from the FTP server
4	>ftp_close(A1)

Related functions:

ftp_put()

ftp_mget()^{^[541]}^{^[542]}

Description:

Download multiple files from a FTP server.

Syntax:

ftp_mget(client,serverFolder,localFolder,multiServerFiles)

Note:

This is an external library function. When parameter serverFolder is a relative path, it is relative to the current working directory; when it is preceded by a slash sign (/), it is an absolute path. The parameter can be absent, but its position must be kept by retaining the comma. If the parameter is an empty string or is absent, the folder path is relative to the current working directory.

When parameter localFolder is a relative path, it is relative to the path configured in esProc Options -> Main directory. The parameter can be absent, but its position must be kept by retaining the comma. If the parameter is an empty string or is absent, the folder path is relative to the path configured in esProc Options -> Main directory.

For a wildcard character, the question mark (?) signifies a single character, an asterisk (*) signifies any character, and double asterisk (**) signifies any character plus a directory.

Options:

@f	Overwrite a namesake file
@t	Skip a namesake file

Parameters:

client	An FTP client object
serverFolder	A server folder
localFolder	A local folder
multiServerFiles	Wildcard-specified server files; can be duplicated

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")
2	=ftp_cd(A1,"/ WorkingDirectory ")
3	*=ftp_mget@f(A1,"folder1","G:/download",".doc")**	Download files suffixed by doc under folder1 directory to G:/download directory while overwriting namesake files
4	*=ftp_mget@f(A1,"folder1","G:/download",".xls",".xlsx")*	Download files suffixed by xls and xlsx under folder1 directory to G:/download directory
5	=ftp_mget@f(A1,"folder1","G:/download","")**	Download all files under folder1 directory to G:/download directory
6	*=ftp_mget@t(A1,"folder2","G:/download",".docx")**	Download files suffixed by docx under folder2 directory to G:/download directory while skipping namesake files
7	>ftp_close(A1)

Related functions:

ftp_mput()

ftp_put()

ftp_mput()^{^[543]}^{^[544]}

Description:

Upload multiple files onto a FTP server.

Syntax:

ftp_put(client,serverFolder,localFolder,multiLocalFiles)

Note:

For a wildcard character, the question mark (?) signifies a single character, an asterisk (*) signifies any character, and double asterisk (**) signifies any character plus a directory.

Options:

@f	Overwrite a namesake file
@t	Skip a namesake file

Parameters:

client	An FTP client object
serverFolder	A server folder
localFolder	A local folder
multiLocalFiles	Wildcard-specified server files; can be duplicated

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")
2	=ftp_cd(A1,"/ WorkingDirectory ")
3	*=ftp_mput@f(A1,"folder1","G:/upload",".doc")**	Upload files suffixed by doc under G:/upload directory to folder1 directory while overwriting namesake files
4	*=ftp_mput@f(A1,"folder1","G:/upload",".xls",".xlsx")*	Upload files suffixed by xls and xlsx under G:/upload directory to folder1 directory
5	=ftp_mput@f(A1,"folder1","G:/upload ","")**	Upload all files under G:/upload directory to folder1 directory
6	*=ftp_mput@t(A1,"folder2","G:/upload,".docx")**	Upload files suffixed by docx under G:/upload directory to folder2 directory while skipping namesake files
7	>ftp_close(A1)

ftp_put()[545][546]

Description:

Upload a file to the FTP server.

Syntax:

ftp_put(client,remoteFile,localFile)

Note:

External library function. If the parameter localFile is a relative path, it is relative to the path to the current dfx file.

Options:

@f	Overwrite the local namesake file

Parameters:

client	An FTP client object
remoteFile	A remote file
localFile	A local file

Example:

	A
1	=ftp_client("192.168.75.1":21,"Administrator","admin")
2	=ftp_cd(A1,"/WorkingDirectory")
3	=ftp_put(A1,"Records_Upload.docx","G:/Records.docx")	Upload a file to the FTP server
4	>ftp_close(A1)

Related functions:

ftp_get()

func()[547][548]

Here’s how to use func() function.

func()[549][550]

Description:

Call a subroutine.

Syntax:

func(c,x_i)

Note:

A subroutine can be called in any cell as required once defined in a program cellset. The function calls a subroutine starting from master cell c and, in the meantime, passes in parameter x_i and makes it the value of c. Return the return value defined by the subroutine after the call is completed.

Parameters:

c	The master cell of a subroutine; it is usually the cell where the func is located
x_i	The parameter used in a subroutine; can be a numerical value, a sequence, or other types of value

Return value:

The return value of the subroutine.

Example:

	A	B
1	func		Define a subroutine Return the sum of the members of the passed parameter – whose value is a sequence
2		return A1.sum()
3	=func(A1,[1,2,3])		Calling method; the return value is 6

func …{return x_i}[551][552]

Description:

Define a function block.

Syntax:

func

…

{return x_i}

Note:

The function defines a function block, which may or may not return a result after computation. The function block (subroutine) begins with the starting characters func and covers a cell range where the master cell is the one holding the func. The return statement is used to return the function’s result and terminate the execution of the function block. The subroutine will by default return the value of the last calculation cell if no return statement appears during execution.

Return value:

The result of the function block.

Example:

	A	B
1	func		Define a subroutine where the parameter passed in is a sequence and that returns the sum of members of the sequence
2		return A1.sum()

Related functions:

func()

Fv()[553][554]

Description:

The function equals the Excel FV function.

Syntax:

Fv(rate,nper,pmt,pv)

Note:

The function calculates the future value of an investment (i.e. the sum of principal amount and interest obtained after the investment ends) with periodic constant payments and a constant interest rate.

Parameters:

rate	The interest rate per period; it is a fixed value
nper	The number of periods over which the investment (or loan) requires or is to be paid
pmt	The amount paid per period, which keeps unchanged during the whole period of paying off the loan. To omit it, pv must exist
pv	The present value of the loan /investment, known as the principal. That is the money that already exist when the payment for an investment (or a loan) begins, or an accumulated sum of present values of a series of future payments

Options:

@t	Indicating the pamyment type, it corresponds to the Excel type parameter. If using the option, choose type 1; if not, choose type 0.
@p(rate,nper,pmt,fv)	This option makes the function equivalent to Excel PV functionand calculates the present value of an investment that is the total amount of a series of future payments. For example the amount of borrower’s borrowed money is the present value of the loan delivered by the lender.

Example:

Fv@t(0.07, 30,-2000,0,1)	202146.08273281078
*Fv@p(0.067/12,1225,500,0)**	-72700.0451136414

Fvdb()[555][556]

Description:

The function equals the Excel VDB function.

Syntax:

Fvdb(cost,salvage,life,start_period,end_period,factor)

Note:

The function calculates the depreciation of an asset for a specfied period, using variable declining balance method, or double-declining balance method or another user-defined method.

Parameters:

cost	The initial cost of the asset
salvage	The value of the asset at the end of the depreciation (also known as asset residual value)
life	The number of periods over which the asset is to be depreciated (sometimes called expected useful life of the asset)
start_period	The starting period for which you want to calculate the depreciation. It must use the same unit as life.
end_period	The ending period for which you want to calculate the depreciation. It must use the same unit as life.
factor	The rate of depreciation. If omitted, it takes on the default value of 2, specifying the double-declining balance method

Options:

@s	Do not switch to the straight-line depreciation method when depreciation is greater than the declining balance calculation

Example:

Fvdb(100000, 10000,10, 0,1)	20000.0
Fvdb@s(100000, 10000,120, 6,18,1.5)	12992.03902742642

Fyield()[557][558]

Description:

The function equals the ExcelYIELD, YIELDDISC or YIELDMAT functions.

Syntax:

Fyield(settlement,maturity;rate,pr,redemption)	Equivalent to Excel YIELD function. It calculates the yield rate of a security. Annually. Specify the day count basis method US (NASD) 30/360.
Fyield@d(settlement,maturity;0,pr,redemption)	Equivalent to Excel YIELDDISC function. It calculates the annual yield rate of a discounted security. Specify the day count basis method US (NASD) 30/360.
Fyield@m(settlement,maturity,issue;rate,pr)	Equivalent to Excel YIELDMAT function. It calculates the yield rate of a security that pays interest at maturity. Specify the day count basis method US (NASD) 30/360.

Note:

The function returns the yield rate of a security that pays periodic interest

Parameters:

settlement	The security's settlement date
maturity	The security's maturity date
rate	The security's annual coupon rate
pr	The security's price
redemption	The security's redemption value
issue	The security’s issue date

Options：

@2	Semi-annually. It corresponds to the Excel frequency parameter.
@4	Quaterly. It corresponds to the Excel frequency parameter.
@1	Specify the day count basis method Actual/Actual. It corresponds to the Excel basis parameter.
@0	Specify the day count basis method Actual/360. It corresponds to the Excel basis parameter.
@5	Specify the day count basis method Actual/365. It corresponds to the Excel basis parameter.
@e	Specify the day count basis method European 30/360. It corresponds to the Excel basis parameter.

Example:

Fyield@2(date("2008-2-15"),date("2016-11-15");0.0575,95.04287,100)	0.06500000688109805
Fyield@d0(date("2008-2-16"),date("2008-3-1");0,99.795,100)	0.05282257198685834
Fyield@m(date("2008-3-15"),date("2008-11-3"),date("2007-11-8");0.0625,100.0123)	0.060954333691538576

gcd()[559][560]

Description:

Return the greatest common divisor.

Syntax:

gcd(x_i,…)

gcd(A)

Note:

The function calculates the greatest common divisor of members of [x₁, x₂,…].

Parameter:

A	Sequence
x_i	A numeric expression, which will be ignored if its value is not a number

Return value:

The greatest common divisor

Example:

gcd(7,1)

goto C^{^[561]}^{^[562]}

Description:

Jump to execute cell C.

Syntax:

goto c

Note:

The function enables jumping to execute cell C.

Example:

	A	B	C
1	=2			7
2	if A1>5	>A1=A1+4	>A1=A1+5	Within the if code block, when A1>5 is true, execute B2; otherwise jump to execute C2
3	else	goto C2

group()[563][564]

Here’s how to use group() function.

A.group(x_i,…)[565][566]

Description：

Perform equi-grouping according one or more fields or expressions.

Syntax：

A.group(x_i,…)

Note：

The function performs equi-grouping on a sequence or a record sequence according to a single or multiple fields/expressions. The result is a sequence consisting of groups.

Options：

@o	Group records by comparing adjacent ones, which is equal to the merging operation, and the result set won’t be sorted
@1	Get the first record of each group to form a record sequence and return it (Please note that 1 is a number instead of a letter)
@n	x gets assigned with group numbers which can be used to define the groups. @n and @0 are mutually exclusive
@u	Do not sort the result set by x. It doesn’t work with @o/@n
@i	x is a bool expression. If the result of x is true, then start a new group. This option is equivalent to A.group@o(a+=if(x,1,0)), in which a=0 and there is only one x
@0	Discard the group over which the result of grouping expression x is null. Use it when there’s only one expression x
@s	Perform a concatenation of sequences/records sequences after the grouping. It is equivalent to A.group(xi,…).conj()
@p	Return a sequence of integer sequences, each of which contains the positions of members in each group in sequence A
@h	Used over a grouped table with each group ordered to speed up grouping

Parameters：

A	A sequence
x_i	Grouping expression. When grouping data by multiple fields or expressions, separate grouping expressions from each other by commas

Return value：

A sequence or a record sequence

Example：

Ø Group a sequence

	A
1	[6,9,12,15,16,5,1,7,8]	[[6,12,16,8],[ 9,15,5,1,7]] The series is divided into two groups. Divide the number of members in both groups by 2, one of the remainders is 0 and the other is 1
2	=A1.group(~%2)
3	=A1.group(~%2,~%3)	[[6,12],[16],[8],[9,15],[1,7],[5]] Group the series according to multiple expressions.
4	=[6,9,16,5,1,7,8].group@s(~%2)	Divide the sequence into a group of odd numbers and a group of even numbers, and then concatenate them
5	=A1.group((#-1)\3)	Group sequence A1 every 3 members

Ø Reuse the grouping result

	A
1	=demo.query("select NAME,BIRTHDAY,GENDER from EMPLOYEE")
2	=A1.group(GENDER)	[[Rebecca,Ashley,Rachel,…],[Matthew,Ryan,Jacob,…]], each group is a sequence
3	=A2.new(GENDER:Gender,~.count():Number)	Count members of each group
4	=A2.new(GENDER:Gender,~.avg(age(BIRTHDAY)):Average)	Get different statistical results using the same grouping result

Ø Group data by multiple fields

	A
1	=demo.query("select NAME,GENDER,DEPT,BIRTHDAY from EMPLOYEE")
2	=A1.group(GENDER,DEPT)	Group records by multiple fields
3	=A1.group@o(GENDER)	Records won’t be sorted; only the adjacent ones will be compared and group them together if they are the same. Same records that are not adjacent may be put into different groups, so there may be overlapped groups and the returned result is a set of sequences.
4	=A1.group@1(GENDER)	Return the first record of each group
5	=A1.group@n(if(GENDER=="F",1,2))	x gets assigned with group numbers which can be used to define the groups directly. [[Rebecca,Ashley,Rachel,…],[Matthew,Ryan,Jacob,…]]
6	=A1.group@u(GENDER,DEPT)	Do not sort result set by the sorting field
7	=A1.group@i(GENDER=="F")	Start a new group when GENDER=="F"
8	=A1.group@p(GENDER,DEPT)	Return a sequence of integer sequences, each of which contains the positions of records in a group (grouped by GENDER field and DEPT field) in the original table sequence
9	=file("D:\\Salesman.txt").import@t()
10	=A9.group@0(Gender)	Group the table sequence by GENDER field, while discarding groups with null values
11	=file("D:/emp10.txt").import@t()	For data fiel emp10.txt, every 10 records are ordered by DEPT
12	=A11.group@h(DEPT)	As A11 is segmented and ordered by DEPT, @h option is used to speed up grouping

Related functions：

A.id()

A.group(x:F,…;y:G,…)

A.group(x:F,...;y:G,…)[567][568]

Description：

Group a sequence and then perform aggregate operations.

Syntax：

A.group(x:F,...;y:G,…)

Note：

First group the sequence according to a single or multiple fields/expressions and then aggregate each group of data. After the sequence is grouped according to x, a new table sequence with fields being F,... G,… will be created. Values of F field are the value of x field of the first record in each group and G field gets values by computing y with regard to each group.

Options：

@o	Group records by comparing adjacent ones, which is equal to the merging operation, and the result set won’t be sorted.
@n	x gets assigned with group numbers which can be used to define the groups. @n and @o are mutually exclusive.
@u	Do not sort the result set by x. It doesn’t work with @o/@n
@i	x is a bool expression. If the result of x is true, then start a new group. There is only one x.
@0	Discard the group over which the result of grouping expression x is null
@h	Used over a grouped table with each group ordered to speed up grouping

Parameters：

A	A sequence
x	Grouping expression. If omitting x:F, aggregate the whole set without grouping; in this case ;must not be omitted
F	Field name of the result table sequence
G	Names of summary fields in the result table sequence
y	Aggregate expression in which ~ is used to reference a group

Return value：

A sequence

Example：

	A
1	*=demo.query("select from SCORES")**
2	=A1.group(STUDENTID:StudentID;~.sum(SCORE):TotalScore)
3	=A1.group@o(STUDENTID:StudentID;~.sum(SCORE):TotalScore)	Only the adjacent ones will be compared and group them together if they are the same. The result set won’t be sorted.
4	*=demo.query("select from STOCKRECORDS where STOCKID<'002242'")**
5	=A4.group@n(if(STOCKID=="000062",1,2):StockID;~.sum(CLOSING):TotalPrice)	x gets assigned with group numbers
6	=A1.group(;~.sum(SCORE):TotalScore)	x:F is omitted, so compute the total score of all the students
7	*=demo.query("select from EMPLOYEE")**
8	=A7.group@u(STATE:State;~.count(STATE):TotalScore)	Do not sort result set by the sorting field
9	=A7.group@i((GENDER=="F"):IsF;~.count():Number)	Start a new group when GENDER=="F"
10	=file("D:\\Salesman.txt").import@t()
11	=A10.group@0(Gender:Gender;~.sum(Age):Total)	Discard the groups where GENDER values are null
12	=file("D:/emp10.txt").import@t()	For data file emp10.txt, every 10 records are ordered by DEPT
13	=A12.group@h(DEPT:dept;~.sum(SALARY):bouns)	As A12 are segmented and ordered by DEPT, @h option is used to speed up grouping

Related functions：

A.id()

A.group(x_i,…)

ch.group()[569][570]

Description:

Group records in a channel by comparing each one with its neighbor(s) and return a channel.

Syntax:

ch.group(x)

Note:

The function groups the records in channel ch by expression x, during which each record is compared only with its neighbor(s) and returns a channel containing a series of sequences. This is equivalent to a merge. The resulting set won’t be sorted again. This is an attached computation.

Options:

@i	With this option and with grouping expression x being a bool expression, start a new group if the result of x is true. Be sure there’s only one x in this case.

Parameters:

ch	Channel
x	Grouping expression. Use the comma to separate multiple grouping fields/expressions.

Return value:

Channel

Example:

	A
1	=demo.cursor("select EID,NAME,GENDER,DEPT,SALARY from EMPLOYEE")
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A2.group(GENDER,DEPT)	Group records by GENDER field and DEPT field
5	=A2.fetch()	Attach ch.fetch() function that gets the final result to A2’s channel to fetch and store the existing data in the channel
6	=A3.group@i(GENDER=="F")	Start a new group whenever GENDER=="F"
7	=A3.fetch()	Attach ch.fetch() function that gets the final result to A3’s channel
8	=A1.push(A2,A3)	Be ready to push the data in A1’s cursor into A2’s channel and A3’s channel, but the action needs to wait
9	=A1.skip()	Data in A1’s cursor is pushed into the channel and operations are performed as the skip() operation is performed over A1
10	=A2.result()
11	=A3.result()

cs.group()[571][572]

Description:

Group cursor records by comparing only adjacent records and return the original cursor.

Syntax:

cs.group(x,…)

Note:

The function groups cursor cs containing a set of records by expression x, according to which only the adjacent records are compared, and return the original cursor of sequences. Cursor cs should be ordered. The operation is equal to a merge and supports multicursors.

Options:

@i	x is a bool expression. Begin a new group when a record makes it return true. In this case there should be only one x.
@1	Get the first record of every group to form a record sequence and return it; here it is number 1, instead of letter l
*@q(x:F,…;x’:F’,…;…)*	When the cursor is ordered by the first grouping field, just sort the grouped data by the following field(s); support memory grouping
@s	Sort only without grouping; must work with @q option

Parameters:

cs	A cursor containing a set of records
x	Grouping expression; multiple fields/expressions for grouping will be separated from each other with the comma.

Return value:

The orginal cursor

Example:

	A
1	*=demo.cursor("select from EMPLOYEE")**
2	=A1.group(GENDER,DEPT)	Put adjacent records whose GENDER and DEPT values are equal into same group, and return the original cursor
3	*=demo.cursor("select from EMPLOYEE")**
4	=A3.group@i(GENDER=="F").fetch()	Begin a new group as long as the record satisfies GENDER=="F"
5	*=demo.cursor("select from EMPLOYEE order by GENDER ")**
6	=A5.group@1(GENDER).fetch()	Return the first record of each group
7	*=demo.cursor("select from EMPLOYEE order by DEPT ")**	Retrieve data of EMPLOYEE table, sort it by DEPT and return data as a cursor
8	=A7.group@q(DEPT;GENDER)	A7’s cursor is already ordered by DEPT, so the data just need to be ordred by group by GENDER
9	=A7.group@qs(DEPT:DEPT;GENDER:GENDER).fetch()	Sorted only without grouping

Related functions:

A.group(x_i,…)

A.group(x:F,…;y:G,…)

cs.group()^{^[573]}^{^[574]}

Description:

Group a cluster cursor by comparing each record with its next neighbor.

Syntax:

cs.group(x,…)

Note:

The function groups records in ordered cluster cursor cs according to expression x by comparing the value of x only with its next neighbor, and returns the cluster cursor containing a sequence of groups. The operation is equivalent to a merge and supports multicursors.

Parameters:

cs	A cluster cursor
x	Grouping expression; use comma to separate multiple grouping fields or expressions

Return value:

The grouped cluster cursor

Example:

	A
1	=file@n("D:/employees.ctx","192.168.0.111:8281")	Below is employees.ctx ordered by DEPT field:
2	=A1.create()	Create a cluster composite table
3	=A2.cursor()	Return a cluster cursor
4	=A3.group(DEPT)	Group the cluster cursor by DEPT and return the grouped cluster cursor
5	=A4.fetch()

cs.group (x:F,…;y:G,…)[575][576]

Description:

Group records of a given cursor by comparing each with its neighbours, peform aggregation over each group and return the original cursor.

Syntax:

cs.group(x:F,...;y:G,…)

Note:

The function groups records in cursor cs according to expression x, by which cs is ordered and whose values are only compared with their neighbors, and then performs aggregation. The resulting set won’t be sorted again. After grouping, records in the original cursor will have fields F,... G,…. Values of F field consist of values of x field in the first record of every group, and values of G field are the results of computing expression y over each group. The function supports a multicursor.

Parameters:

cs	Cursor/cluster cursor
x	Grouping expression
F	Field name
G	Aggregation field name
y	Aggregate expression

Return value:

The original cursor/cluster cursor

Example:

	A
1	*=demo.cursor("select from SCORES where STUDENTID <5 order by STUDENTID ")**	Sort records by SCOREs field
2	=A1.group(STUDENTID:StudentID;sum(SCORE):TotalScore)	Return the original cursor cs
3	=A2.fetch()

	A
1	=file@n("D:/employees.ctx","192.168.0.111:8281")	Below is employees.ctx ordered by DEPT field:
2	=A1.create()	Create a cluster composite table
3	=A2.cursor()	Return a cluster cursor
4	=A3.group(DEPT:dept;count(NAME):count)	Group the cluster cursor according to DEPT by comparing each record with its next neighbor, perform aggregation and return the grouped cluster cursor
5	=A4.fetch()

groupi()^{^[577]}^{^[578]}

Here’s how to use groupi() function.

A.groupi(D_i,…)^{^[579]}^{^[580]}

Description:

Generate a sequence for use in a data-input sheet.

Syntax:

A.groupi(D_i,…)

Note:

The function generate a sequence for use in a data-input sheet whose dimension is parameter D_i. The values of column D_i is A.group(D₁).(~.group(D₂).(…(~.id(Di))).

Options:

@o	Assume that the sequence is ordered, perform a merge by comparing each record with its next neighbor and won’t sort the result set

Parameters:

A	A sequence
D_i	A data-input sheet’s dimension

Return value:

A sequence

Example:

	A
1	=demo.query("select * from employee")	Return a table sequence
2	=A1.groupi(GENDER,STATE,DEPT,NAME)	Group data in columns GENDER,STATE and DEPT and perform distinct over column NAME
3	=demo.query("select * from employee order by GENDER,STATE,DEPT")	Return a table sequence and sort it by GENDER,STATE and DEPT
4	=A3.groupi@o(GENDER,STATE,DEPT,NAME)	Since A3’s table sequence is already ordered, perform a merge by comparing neighboring records; this gets the same result as A2’s but is faster

groupn()^{^[581]}^{^[582]}

Here’s how to use group() function.

cs.groupn(x;C)^{^[583]}^{^[584]}

Description:

Group records in a cursor and push them respectively into a sequence of channels.

Syntax:

cs.groupn(x;C)

Note:

The function groups records in cursor cs and pushes them respectively into a sequence of channels.

Parameters:

cs	Cursor records
x	Grouping expression
C	A sequence of channels

Return value:

The original cursor

Example:

	A
1	=demo.cursor("select NAME,GENDER,DEPT,BIRTHDAY from EMPLOYEE")
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A1.groupn(if(GENDER=="F",1,2);[A2,A3])	Group cursor records, and push one group where GENDER is F into A2’s channel and the other group into A3’s channel
5	=A2.fetch()	Keep data in the channel in place
6	=A3.fetch()	Keep data in the channel in place
7	=A1.fetch()
8	=A2.result()	Get result from A2’s channel
9	=A3.result()	Get result from A3’s channel

ch.groupn(x;C)^{^[585]}^{^[586]}

Description:

Group records in channel ch and push them respectively into a sequence of channels.

Syntax:

ch.groupn(x;C)

Note:

The function groups records in channel ch and pushes them respectively into a sequence of channels.

Parameters:

ch	Channel
x	Gouping expression
C	A sequence of channels

Return value:

A channel

Example:

	A
1	=demo.cursor("select NAME,GENDER,DEPT,BIRTHDAY from EMPLOYEE")
2	=channel(A1)	Push cursor records into a sequence of channels and return a channel
3	=channel()	Create a channel
4	=channel()	Create a channel
5	=A2.groupn(if(GENDER=="F",1,2);[A3,A4])	Group records of A2’s channel, and push one group where GENDER is F into A3’s channel and the other group into A4’s channel
6	=A3.fetch()	Attach ch.fetch() function that gets the final result set to A3’s channel but keep data in A3’s channel in place
7	=A4.fetch()	Attach ch.fetch() function that gets the final result set to A4’s channel but keep data in A4’s channel in place
8	=A1.fetch()
9	=A3.result()	Get result from A3’s channel
10	=A4.result()	Get result from A4’s channel

cs.groupn(x;F)^{^[587]}^{^[588]}

Description:

Group records of a cursor and write the subset groups as a sequence of bin files.

Syntax:

cs.groupn(x;F)

Note:

The function groups records of cursor cs and writes the subset groups as a sequence of bin files.

Parameters:

cs	Cursor records
x	Grouping expression
F	A sequence of bin file objects

Return value:

The original cursor

Example:

	A
1	=demo.cursor("select NAME,GENDER,DEPT,BIRTHDAY from EMPLOYEE")
2	=[file("f_dept.btx"),file("m_dept.btx")]	A sequence of bin file objects
3	=A1.groupn(if(GENDER=="F",1,2);A2)	Put records where GENDER is F into the first group and other records into the second group, and then write the subset groups into a sequence of bin files in order
4	=A3.fetch()

groups()[589][590]

Here’s how to use groups() function.

A.groups()[591][592]

Description:

Group a table sequence and then get the aggregate result cumulatively.

Syntax:

A.groups(x:F,…;y:G,…)

Note:

The function groups and aggregates table sequence A simultaneously by one or multiple fields/expressions to generate a new table sequence with F,.. G… as the fields. Namely, during the traversal through members of A, they will be placed to the corresponding result set one by one while a result set is aggregated cumulatively. Compared with the method of first grouping and then aggregation, the function has a better performance.

Options:

@o	Group records by comparing adjacent ones, which is equal to the merging operation, and the result set won’t be sorted.
@n	x gets assigned with group numbers which can be used to define the groups. @n and @o are mutually exclusive.
@u	Do not sort the result set by x. It doesn’t work with @o/@n
@i	x is a bool expression. If the result of x is true, then start a new group. There is only one x.
@m	Use parallel algorithm to handle data-intensive or computation-intensive tasks; no definite order for the records in the result set; can’t be used with @oi options.
@0	Discard the group over which the result of grouping expression x is null
@h	Used over a grouped table with each group ordered to speed up grouping

Parameters:

A	A sequence.
x	Grouping expression.
F	Field name of the result table sequence.
y	y is the function with which A is traversed. When y is an aggregate function, it only supports sum/count/max/min/top/avg/iterate/icount/median. When the function work with iterate(x,a;G_i,…) function, the latter’s parameter Gi should be omitted. When y isn’t an aggregate function, perform calculation over only the first record in each group.
G	Summary field name in the result table sequence.

Return value:

Post-grouping table sequence.

Example:

	A
1	*=demo.query("select from SCORES where CLASS = 'Class one'")**
2	=A1.groups(STUDENTID:StudentID;sum(SCORE):TotalScore)	group by a single field.
3	*=demo.query("select from SCORES")**
4	=A3.groups(CLASS:Class,STUDENTID:StudentID;sum(SCORE):TotalScore)	group by multiple fields.
5	=A3.groups@m(STUDENTID:StudentID;sum(SCORE):TotalScore)	Use @m option to increase performance of big data handling.
6	=A3.groups@o(STUDENTID:StudentID;sum(SCORE):TotalScore)	Only compare and merge with the neighboring element, and the result set is not sorted.
7	*=demo.query("select from STOCKRECORDS where STOCKID<'002242'")**
8	=A7.groups@n(if(STOCKID=="000062",1,2):StockID;sum(CLOSING):TotalPrice)	The value of x is the group sequence number.
9	*=demo.query("select from EMPLOYEE")**
10	=A9.groups@u(STATE:State;count(STATE):TotalScore)	Do not sort result set by the sorting field.
11	=A9.groups@i(STATE=="California":IsCalifornia;count(STATE):count)	Start a new group when STATE=="California".
12	*=A3.groups(CLASS:Class,STUDENTID:StudentID;iterate(~~2,10): Score1)**	Perform iterate operation within each group
13	=file("D:\\Salesman.txt").import@t()
14	=A13.groups@0(Gender:Gender;sum(Age):Total)	Discard groups where Gender values are nulls
15	=file("D:/emp10.txt").import@t()	For data file emp10.txt, every 10 records are ordered by DEPT
16	=A15.groups@h(DEPT:dept;sum(SALARY):bouns)	A15 is grouped and ordered by DEPT, for which @h option is used to speed up grouping
17	=A4.groups(STUDENTID:StudentID;SUBJECT,sum(SCORE):SUMSCORE)	Parameter y isn’t an aggregate function, so the function performs operation over the first record; the result is English

Note:

Compared with A.group(x:F,…;y:G,…), A.groups(x:F,…;y:G,…) computes in a accumulative way and thus gets a better performance.

Related functions:

A.group(xi,…)

A.group(x:F,...;y:G,…)

ch.groups()[593][594]

Description:

Group records in a channel.

Syntax:

ch.groups(x:F,…;y:G…;n)

Note:

The function groups records in channel ch according to grouping expression x, by which the records are ordered, to get a channel having F,...G,… fields. Sort records in the new channel by x. Values of F field consist of values of x field in the first record of every group, and values of G field are the results of computing expression y, which is an aggregate function executed on cs, over each group. It aims to fetch the grouping result set from the channel.

Options:

@n	With the option the value of expression x is a group number, which points to the desired group
@u	Won’t sort the resulting set by expression x; the option and @n are mutually exclusive

Parameters:

ch	Channel
x	Grouping expression, by which an aggregation over the whole grouped set is performed if x:F is omitted. In that case the semicolon should not be omitted
F	Field names of the resulting table sequence
y	An aggregate function which only supports sum/count/max/min/top /avg/iterate; the parameter Gi should be given up if function iterate(x,a;G_i,…) is used
G	The aggregate fields in the resulting table sequence

Return value:

Channel

Example:

	A
1	*=demo.cursor("select from EMPLOYEE ")**
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=channel()	Create a channel
5	=channel()	Create a channel
6	=A1.push(A2,A3,A4,A5)	Be ready to push the data in A1’s cursor into channel A2, A3 and A5, but the action needs to wait.
7	=A2.groups(;sum(SALARY):TotalSalary)	As x:F is omitted, calculate the sum of salaries of all employees
8	=A3.groups(DEPT:dept;sum(SALARY):TotalSalary)	Group and sort records by DEPT field
9	=A4.groups@n(if(GENDER=="F",1,2):SubGroups;sum(SALARY):TotalSalary)	The value of x is group number; put records where GENDER is “F” into the first group and others into the second group, and then aggregate each group
10	=A5.groups@u(STATE:State;count(STATE):count)	Won’t sort the resulting set by grouping field
11	A1.select(month(BIRTHDAY)==2)
12	A11.fetch()	Attach a fetch operation to A11’s cursor
13	=A2.result()
14	=A3.result()
15	=A4.result()
16	=A5.result()

cs.groups()[595][596]

Description:

Group records in a cluster cursor, sort them by the grouping field and peform aggregation over each group and add each aggregate to the result set.

Syntax:

cs.groups(x:F,…;y:G…;n)

Note:

Options:

@c	Perform the group operation over data in every node and compose the result sets into a cluster memory table in the segmentation way of the cursor; suppport a cluster dimension table
@d	Copy the result sets into nodes to compose a cluster duplicate memory table

Parameters:

cs	Records in a cluster cursor
x	Grouping expression; if omitting parameters x:F, aggregate the whole set; in this case, the semicolon (;) must not be omitted
F	Field name in the result table sequence
y	Aggregate function that only supports sum/count/max/min/top /avg/iterate; when the function works with iterate(x,a;G_i,…) function, the latter’s parameter Gi should be omitted
G	Aggregate field name in the result table sequence
n	The specified maximum number of groups; stop executing the function when the number of data groups is bigger than n to prevent memory overflow; the parameter is used in scenarios when it is predicted that data will be divided into a large number of groups that are greater than n.

Return value:

A table sequence/cluster memory table

Example:

	A
1	=file@n("D:/emp1.ctx","192.168.0.111:8281")	Below is emp1.ctx:
2	=A1.create()	Create a cluster composite table
3	=A2.cursor()	Return a cluster cursor
4	=A3.groups(Dept:dept;count(Name):count)	Group data by DEPT and perform aggregation

	A
1	[192.168.0.110:8281,192.168.18.143:8281]
2	=file@0("emp.ctx", A1)	emp.ctx is a distributed file on nodes 192.168.0.110 and 192.168.18.143
3	=A2.create()	Open a cluster composite table
4	=A3.cursor()	Create a cluster cursor
5	=A4.groups(GENDER:gender;sum(SALARY):totalSalary)	Group data by GENDER and perform aggregation and return result as a table sequence
6	=A3.cursor()
7	=A6.groups@c(GENDER:gender;sum(SALARY):totalSalary).dup()	Retain the way of segmentation of the distributed cursor and return a cluster memory table
8	=A3.cursor()
9	=A8.groups@d(GENDER:gender;sum(SALARY):totalSalary).dup()	Copy the result sets onto nodes to compose a cluster duplicate memory table

Related functions:

cs.groups()^{^[597]}^{^[598]}

Description:

Group records in a cursor.

Syntax:

cs.groups(x:F,…;y:G…;n)

Note:

The function groups records in a cluster cursor by expression x, sorts result by the grouping field, and calculates the aggregate value on each group. This creates a new table sequence consisting of fields F,...G,… and sorted by the grouping field x.The values of F field are the value of x field of the first record in each group and G field gets values by computing y – the aggregate function with which records of cs is aggregated – on each group. The aggregation over a cluster cursor will first be performed by the main process on the local machine and the result will then be returned to the machine that initiates the invocation; the process is called reduce.

Options:

@n		The value of grouping expression is a group number which can be used to locate the group
@u		Do not sort the result set by the grouping expression; it doesn’t work with @n
@o	Compare each record only with its neighboring record to group, which is equivalent to the merge operation, and won’t sort the result set
@i	With this option, the function only has one parameter x that is a bool expression; start a new group if its result is true
@h	Used over a grouped table with each group ordered to speed up grouping

Parameters:

cs	Records in a cursor/cluster cursor
x	Grouping expression; if omitting parameters x:F, aggregate the whole set; in this case, the semicolon (;) must not be omitted
F	Field name in the result table sequence
y	Aggregate function that only supports sum/count/max/min/top/avg/iterate; when the function works with iterate(x,a;G_i,…) function, the latter’s parameter Gi should be omitted
G	Aggregate field name in the result table sequence
n	The specified maximum number of groups; stop executing the function when the number of data groups is bigger than n to prevent memory overflow; the parameter is used in scenarios when it is predicted that data will be divided into a large number of groups that are greater than n; it doesn’t work with @n option. Support a multicuror when this parameter is absent.

Return value:

Post-grouping table sequence

Example:

	A
1	*=demo.cursor("select from SCORES where CLASS = 'Class one'")**
2	=A1.groups(;sum(SCORE):TotalScore)	As parameters x:F absent, calculate the total score of all students
3	*=demo.cursor("select from FAMILY")**
4	=A3.groups(GENDER:gender;sum(AGE):TotalAge)	Group and order data by specified fields
5	*=demo.cursor("select from STOCKRECORDS where STOCKID<'002242'")**
6	=A5.groups@n(if(STOCKID=="000062",1,2):SubGroups;sum(CLOSING):ClosingPrice)	The value of grouping expression is group number; put records whose STOCKID is “000062” to the first group and others to the second group; and meanwhile aggregate each group
7	*=demo.cursor("select from EMPLOYEE")**
8	=A7.groups@u(STATE:State;count(STATE):Total)	The result set won’t be sorted by the grouping field
9	*=demo.cursor("select from EMPLOYEE")**
10	=A9.groups@o(STATE:State;count(STATE):Total)	Compare each record with its next neighbor and won’t sort the result set
11	*=demo.cursor("select from EMPLOYEE")**
12	=A11.groups@i(STATE=="California":IsCalifornia;count(STATE):count)	Start a new group if the current record meets the condition STATE=="California"
13	=file("D:/emp10.txt").cursor@t()	For data file emp10.txt, every 10 records are ordered by DEPT
14	=A13.groups@h(DEPT:DEPT;sum(SALARY):bouns)	As A13 is grouped and ordered by DEPT, use @h option to speed up grouping
15	*=demo.query("select from employee")**
16	=A15.cursor@m(3)	Return a multicursor
17	=A16.groups(STATE:state;sum(SALARY):salary)	Group the multicursor with groups function

groupx()[599][600]

Here’s how to use groupx() function.

ch.groupx()[601][602]

Description:

Group records in a channel and return a channel.

Syntax:

ch.groupx(x:F,…;y:G…)

Note:

The function groups records in channel ch according to expression x, by which the records are ordered, to get a channel having F,...G,… fields. Values of F field consist of values of x field in the first record of every group, and values of G field are the results of computing expression y, which is an aggregate function executed on ch, over each group. It aims to fetch the grouping result set from the channel.

Options:

@n	With the option the value of expression x is a group number, which points to the desired group

Parameters:

ch	Channel
x	Grouping expression
F	Field name in the resulting table sequence
y	An aggregate function which only supports sum/count/max/min/top /avg/iterate; the parameter Gi should be given up if function iterate(x,a;G_i,…) is used
G	The aggregate fields in the resulting table sequence

Return value:

Channel

Example:

	A
1	*=demo.cursor("select from EMPLOYEE ")**
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A1.push(A2,A3)	Be ready to push the data in A1’s cursor into A2’s channel and A3’s channel, but the action needs to wait
5	=A2.groupx(DEPT:dept;sum(SALARY):TotalSalary)	Group and sort records by DEPT field
6	=A3.groupx@n(if(GENDER=="F",1,2):SubGroups;sum(SALARY):TotalSalary)	The value of expression x is a group number; put records where GENDER is “F” into the first group and others into the second group, and then aggregate each group
7	=A1.select(month(BIRTHDAY)==2)
8	=A1.fetch()	Attach a fetch operation to A7’s cursor
9	=A2.result()	Return the result as a cursor
10	=A3.result()	Return the result as a cursor

cs.groupx()[603][604]

Description:

Group the ordered records in a cursor and return result as a cursor.

Syntax:

cs.groupx(x:F,…;y:G…;n)

Note:

The function groups records in a cursor by grouping expression x to create a new cursor consisting of fields F,...G,… sorted by the grouping field x. The values F field are the value of x field of the first record in each group and G field gets values by computing y – the aggregate function with which records of cs is aggregated – on each group.

Options:

@n	Parameter n will be treated as a grouping expression to perform intra-grouping within the memory; x gets assigned with group numbers which can be used to define the groups.
@u	Won’t sort the result set by parameter x; mutually exclusive with @n.

Parameters:

cs	Records in a cursor
x	Grouping expression
F	Result field name
y	Aggregate function which only supports sum/count/max/min/top/ avg/iterate. When the function works with the iterate(x,a;G_i,…) function, the latter’s parameter Gi should be omitted
G	Aggregate field name
n	Number of buffer rows; its value is n times of the default if n is less than 1

Return value:

Cursor

Example:

	A
1	*=demo.cursor("select from SCORES where CLASS='Class one'")**
2	=A1.groupx(STUDENTID:ID;sum(SCORE):Scores).fetch()
3	*=demo .cursor("select from FAMILY")**
4	=A3.groupx@n(if(GENDER=="Male",1,2):ID;sum(AGE):TotalAge).fetch()	The value of grouping expression is a group number. Put records whose GENDER is "Male" to the first group, and others to the second group. Meanwhile, aggregate every group of records
5	*=demo.cursor("select from EMPLOYEE")**
6	=A5.groupx@u(STATE:State;count(STATE):TotalScore).fetch()	The result set isn’t sorted

Related functions:

cs.groupx()^{^[605]}^{^[606]}

Description:

Group records in a cluster cursor and return a synchronously segmented cursor.

Syntax:

cs.groupx(x:F,…;y:G…;n)

Note:

The function groups records in cluster cursor csby grouping expression x to create a new cluster cursor consisting of fields F,...G,… sorted by the grouping field x. The values F field are the value of x field of the first record in each group and G field gets values by computing y – the aggregate function with which records of cs is aggregated – on each group.

Options:

@c	Won’t merge result sets returned by the nodes but return a cluster cursor segmented in the same way

Parameters:

cs	A cluster cursor
x	Grouping expression
F	Resulting field name
y	Aggregate function that only supports sum/count/max/min/top/avg/iterate; when the function works with iterate(x,a;G_i,…) function, the latter’s parameter Gi should be omitted
G	Aggregate field name
n	Number of buffer rows

Return value:

A cluster cursor

Example:

	A
1	[192.168.31.72:8281, 192.168.31.72:8291]
2	=file@0z("orderpart.ctx", A1)	Open a cluster distributed file
3	=A2.create()	Open a cluster composite table
4	=A3.cursor()	Return a cluster cursor
5	=A4.groupx(EID:ID;count(~):IdCount)	Group A7 and perform count by EID, and return a cluster cursor
6	=A5.fetch()
7	=A3.cursor()
8	=A7.groupx(if(EID==4,1,2):ID;count(~):IdCount)	Put records where EID is 4 into the first group and others into the second group, and then count the EID values
9	=A8.fetch()

	A
1	[192.168.0.110:8281,192.168.18.143:8281]
2	=file@0("emp.ctx", A1)	emp.ctx is a distributed file on nodes 192.168.0.110 and 192.168.18.143
3	=A2.create()	Open a cluster composite table
4	=A3.cursor()	Create a cluster cursor
5	=A4.groupx@c(GENDER:gender;sum(SALARY):totalSalary)	Perform group and aggregate operations over A4’s cluster cursor by GENDER without merging result sets returned by nodes and return a cluster cursor having the same segmentation way as A4’s
6	=A5.fetch()	Fetch data from the cluster cursor

hash()[607][608]

Description:

Return a hash value.

Syntax:

hash(x_i,…;n)

Note:

The function calculates the hash value(s) over data items x_i,… and returns a positive integer less than parameter n.

Parameters:

x_i	Data of any type
n	An integer greater than 1

Return value:

A positive integer

Example:

=hash(0.2;38)	7
=hash(2,52,94;100)	28
=hash("abc";10477)	2068

hbase_close()[609][610]

Description:

Close a HBase connection.

Syntax:

hbase_close(con)

Note:

This external library function closes HBase connections.

Parameters:

con

Database connection string

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")
2	=hbase_close(A1)	Close the HBase connection

Related functions:

hbase_cmp()[611][612]

Description:

Compare data with the HBase-supplied comparator.

Syntax:

hbase_cmp(str[,r][,b]) Compare the current value with the threshold

Note:

This external library function compares data with the HBase-supplied comparator.

Options:

@p	Match the current value with the prefix
@n	Check if the current value is null but won’t perform matching
@r	Use a regular expression to match table data
@s	Use the threshold and table data, both of which are string type, to match up a string
@l	Convert a string type or a date/time/datatime type parameter to a Long type one
@b	Perform bit-level comparison using AND, OR and XOR operations

Parameters:

str

A string

Only use this parameter with @r option; its value can only be one of the following letters:

i=case insensitive (Case-insensitive)

m=multiline, (^ and $ can match up a line break within a string)

d=dotall, (The dot symbol can match up a line break)

u=unicode case, (Case-insensitive in matching up Unicode characters )

q=canon_eq (Consider same characters in different character encodings as equal)

x=unix_lines, (Consider \n as a line break only)

l=literal, (Text mode)

c=comments (Comment mode)

The value must be in quotation marks.

Only use this parameter with @b option; its value can only be one of the following: AND, OR, XOR; the value must be in quotation marks.

Return value:

Comparator handle

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")
2	=hbase_cmp("13")
3	=hbase_filter("ValueFilter","eq",A2)
4	=hbase_scan(A1,"emp";filter:A4)
5	=hbase_cmp@p("136")
6	=hbase_scan(A1,"emp";filter:hbase_filter("ValueFilter","eq",A5))
7	=hbase_cmp@r("J","i")
8	=hbase_scan(A1,"emp";filter:hbase_filter("ValueFilter","eq",A7))
9	=hbase_cmp@s("sp")
10	=hbase_scan(A1,"emp";filter:hbase_filter("SingleColumnValueFilter","company","name","=",A9))

Related functions:

hbase_filter()

hbase_filter()[613][614]

Description:

Filter data with the HBase-supplied filter.

Syntax:

hbase_filter(filterName,filterArg) Different filterName values represent different numbers and types of specific parameters, as shown in the following:

hbase_filter(ColumnCountGetFilter,n)	Get the first n values from each row
hbase_filter(ColumnPaginationFilter,limit,columnOffset)	For each row, get field values, whose number is limit, starting from the (columnOffset+1)^th column
hbase_filter(ColumnPrefixFilter,str)	For each row, get field values whose corresponding column names have a prefix which can match up str
hbase_filter(ColumnRangeFilter,minColumn,boolean,maxColumn,boolean)	For each row, get values whose corresponding column names fall in a certain range; the parameter boolean indicates an open interval – when the value is false, or a closed interval – when the value is true
hbase_filter(DependentColumnFilter,family,qualifier)	Specify a column and perform filtering to get columns whose timestamp is different
hbase_filter(FamilyFilter,ifequal,my-family)	Specify a column family, whose name is my-family, to perform the filtering; the value of ifequal can be “=”, “！=”, etc.
hbase_filter(FirstKeyOnlyFilter)	Get the first value from each row
hbase_filter(FirstKeyValueMatchingQualifiersFilter,column)	Get the first value from each row that satisfies the specified column qualifier
hbase_filter(FuzzyRowFilter,fuzzyKeysData)	Perform matching over fuzzy row key. Take a list parameter (List>) to do this. The list has a pair of byte arrays, in which the first one is the row key format, and the second one’s value is 0 or 1. 0 means a byte at same position in row key must match; 1 means a byte at same position in row key can be different.
hbase_filter(InclusiveStopFilter,stopRowKey)	Stop data scanning if a specified row is reached
hbase_(KeyOnlyFilter)	Will only return the key components, like rowkey, column family name, column name and timestamp
hbase_filter(MultipleColumnPrefixFilter,prefixes1,prefixes2,...prefixesN)	Allow to specify multiple column prefixes
hbase_filter(PageFilter,n)	Pigination filter for displaying n rows
hbase_filter(PrefixFilter,str)	Specify a prefix for rowkey
hbase_filter(QualifierFilter,cmp,cmpColumn)	To filter based on column qualifier; cmp is a comparison operator like equal (or=) and not equal (or !=); cmpColumn is column qualifier filtered out through comparator.
hbase_filter(RowFilter,cmp,cmpRow)	To filter based on row key; cmp is a comparison operator like equal (or=) and not equal (or !=); cmpColumn is row key filtered out through comparator.
hbase_filter(ValueFilter,cmp,cmpValue)	To filter based on vlaue ; cmp is a comparison operator like equal (or=) and not equal (or !=); cmpColumn is a value filtered out through comparator.
hbase_filter(SingleColumnValueExcludeFilter,family,columnName,ifequal,cmpValue)/ hbase_filter(SingleColumnValueFilter,family,columnName,ifequal,cmpValue	Filter rows based on specified column value; family is the column family name, ifequal is comparison operator, and cmpValue is the result filtered out through comparator. columnName column will be excluded with SingleColumnValueExcludeFilter, while included with SingleColumnValueFilter.
hbase_filter(RandomRowFilter,n)	Filter rows randomly and return a random result set with a certain probability. To perform same RandomRowFilter on same data set for multiple times, different result sets will be returned. Paramameter n is float type; all rows will be filtered away if n<=0, and all will be kept if n>=1.
hbase_filter(SkipFilter,hbase_filter(ValueFilter,ifequal,cmpValue))	A wrapper filter that filters an entire row if any of the cell is ineligible; work with ValueFilter.
hbase_filter(WhileMatchFilter,hbase_filter())	A wrapper filter that stops scanning as soon as the filtering condition is met.
hbase_filter(TimestampsFilter,timeStamp,boolean)	Return only values whose timestamps match up the specified timestamp.

Note:

This external library function filters data with the HBase-supplied filter.

Parameters:

filterName	HBase filter name
filterArg	Filter parameter

Return value:

Filter handle

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")
2	=hbase_scan(A1,"emp")	All data of the emp table
3	=hbase_filter("ColumnCountGetFilter",3)
4	=hbase_scan(A1,"emp";filter:A3)	rowkey is a row name, and doesn’t belong to data columns
5	=hbase_filter("ColumnPaginationFilter",2, 2)
6	=hbase_scan(A1,"emp";filter:A5)
7	=hbase_filter("ColumnPrefixFilter","na")
8	=hbase_scan(A1,"emp";filter:A7)
9	=hbase_filter("ColumnRangeFilter","age", true, "name",false)
10	=hbase_scan(A1,"emp";filter:A9)
11	=hbase_filter("DependentColumnFilter","family","age")
12	=hbase_scan(A1,"emp";filter:A11)
13	=hbase_filter("FamilyFilter","=",hbase_cmp@s("family"))
14	=hbase_scan(A1,"emp";filter:A13)
15	=hbase_filter("KeyOnlyFilter")
16	=hbase_scan(A1,"emp";filter:A15)
17	=hbase_filter("FirstKeyOnlyFilter")
18	=hbase_scan(A1,"emp";filter:A17)
19	=hbase_filter("FuzzyRowFilter","row1",[1,1,0,0])
20	=hbase_scan(A1,"emp";filter:A19)
21	=hbase_filter("InclusiveStopFilter","row3")
22	=hbase_scan(A1,"emp";filter:A21)
23	=hbase_filter("MultipleColumnPrefixFilter","na","tel","position")
24	=hbase_scan(A1,"emp";filter:A23)
25	=hbase_filter("PrefixFilter","ro")
26	=hbase_scan(A1,"emp";filter:A25)
27	=hbase_filter("QualifierFilter","eq", hbase_cmp@s("name"))
28	=hbase_scan(A1,"emp";filter:A27)
29	=hbase_filter("RowFilter","eq", hbase_cmp("row1"))
30	=hbase_scan(A1,"emp";filter:A29)
31	=hbase_filter("ValueFilter","=", hbase_cmp("C++"))
32	=hbase_scan(A1,"emp";filter:A31)
33	=hbase_filter("SingleColumnValueFilter","family","tel" ,"eq",hbase_cmp@s("13"))
34	=hbase_scan(A1,"emp";filter:A33)
35	=hbase_filter("SingleColumnValueExcludeFilter","family","tel" ,"eq",hbase_cmp@s("13"))
36	=hbase_scan(A1,"emp";filter:A35)
37	=hbase_filter("SkipFilter",hbase_filter("ValueFilter","=", hbase_cmp@s("aaa")))
38	=hbase_scan(A1,"emp";filter:A37)
39	=hbase_filter("FirstKeyValueMatchingQualifiersFilter","name")
40	=hbase_scan(A1,"emp";filter:A39)
41	=hbase_filter("TimestampsFilter",1488855959195,1488855959219,1488855959145,false)
42	=hbase_scan(A1,"emp";filter:A41)
43	=hbase_filter("RandomRowFilter",0.5)	Filer rows at random

Related functions:

hbase_cmp()

hbase_filterlist()[615][616]

Description:

Filter data with multiple filters.

Syntax:

hbase_filterlist(filterHandle1,filterHandle2,...filterHandleN)

Note:

This external library function can accommodate another hbase_filterlist() function within it. By default the filtering conditions in all filters must be met at the same time.

Options:

@o	Every filter is independent in filtering data.

Parameters:

filterHandle

Filter handle

Return value:

Filter handle

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")
2	=hbase_filter("ColumnPaginationFilter",2, 0)
3	=hbase_scan(A1,"emp";filter:A2)
4	=hbase_filter("ColumnPrefixFilter","na")
5	=hbase_scan(A1,"emp";filter:A4)
6	=hbase_filterlist(A2,A4)
7	=hbase_filterlist@o(A2,A4)
8	=hbase_scan(A1,"emp";filter:A6)
9	=hbase_scan(A1,"emp";filter:A7)

Related functions:

hbase_filter()

hbase_get()[617][618]

Description:

Query data in HBase database and return a single row.

Syntax:

hbase_get(client,tableName,rowName,family:column:type:alias,family2:column2:type:alias2,...;filter:f,timeRange:[t1,t2],timeStamp:t)

Note:

This external library function queries a HBbase database to return a sing-row table sequence.

Parameters:

client	Database connection information
tableName	Table name
rowName	Row name
family	Column family name
column	Colum name
type	Data type; can be omitted
alias	Another name of a column; can be omitted
filter:f	‘filter:’ is a fixed format, and parameter f means filter handle; can be omitted
timeRange:[t1,t2]	‘timeRange:’ is a fixed format, and parameters t1 and t2 specify a range of timestamp; can be omitted
timeStamp:t	‘timeStamp:’ is a fixed format, and parameter t is timestamp; can be omitted

Return value:

Table sequence

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")
2	=hbase_scan(A1,"emp")	Query all table data
3	=hbase_get(A1,"emp","row3","company:name"::cname,"company:position":string:cpos,"family:tel":string)	Find a row whose rowkey is row3, and rename column names

Related functions:

hbase_open()[619][620]

Description:

Create a HBase connection.

Syntax:

hbase_open(hdfsUrl, zkUrl1,zkUrl2,...zkUrlN)

Note:

This external library function connect to a HBase database. The format of parameter hdfsUrl is :hdfs://ip, and the format of parameter zkUrl is :zkServerIp. Can connect to multiple nodes.

Parameters:

hdfsUrl	HDFS connection information
zkUrl	Zookeeper connection information

Return value:

Cursor

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")	Connet to a HBase database
2	=hbase_open("hdfs://192.168.0.76", "192.168.0.76, master, 192.168.1.66")

hbase_scan()[621][622]

Description:

Query a HBase database and return result as a cursor or a table sequence.

Syntax:

hbase_scan(client,tableName,rowName,family:column:type:alias,family2:column2:type:alias2,...;rowPrefix:x,filter:f,startRow:startrow,stopRow:stoprow,timeRange:[t1,t2],timeStamp:t)

Note:

This external library function gets data from an HBase database and by default returns a table sequence. Return a cursor when there’s @c option.

Options:

@c	Return a cursor

Parameters:

client	Database connection information
tableName	Table name
rowName	Row name
family	Column family name
column	Column name
Type	Data type; can be omitted
alias	Another name of a column; can be omitted
rowPrefix:x	‘rowPrefix:’ is a fixed format; parameter x is the prefix of rowKey
filter:f	Filter handle
startRow:startrow	‘startRow:’ is a fixed format; parameter startrow represents the starting row, which will be included in data retrieval
stopRow:stoprow	‘stopRow:’ is a fixed format; parameter stoprow represents the ending row, which will be excluded in data retrieval
timeRange:[t1,t2]	‘timeRange:[,]’ is a fixed format; parameter t1 is the starting timestamp whose value will be retrieved, and parameter t2 is the ending timestamp whose value won’t be retrieved
timeStamp:t	Timestamp

Return value:

A table sequence/cursor

Example:

	A
1	=hbase_open("hdfs://192.168.0.8", "192.168.0.8")
2	=hbase_scan(A1,"emp")	Query all table data
3	=hbase_scan@c(A1,"emp")	Return a cursor
4	=A3.fetch()
5	=hbase_filter("SingleColumnValueFilter","family","tel","=",hbase_cmp@s("13"))
6	=hbase_scan(A1,"emp";filter:A5)	Return data filtered out by A5
7	=hbase_scan(A1,"emp","company:name":string:cname,"company:position":string:cpos,"family:tel":string;filter:A5,startRow:row3,stopRow:row7)	Get data from row3 to row7, which is excluded, from A5’s filtered data
8	=hbase_scan(A1,"emp","company:name":string:cname,"company:position":string:cpos,"family:tel":string;filter:A5,rowPrefix:row1)	Get a row whose prefix is row1 from A5’s filtered data
9	=hbase_scan(A1,"emp","company:name":string:cname,"company:position":string:cpos,"family:tel":string;filter:A5,startRow:row3,stopRow:row7,timeStamp:1488855958071)
10	=hbase_scan(A1,"emp","company:name":string:cname,"company:position":string:cpos,"family:tel":string;filter:A5,startRow:row3,stopRow:row7,timeRange:[1488855958071,1488855958255])

Related functions:

hbase_cmp()

hdfs_client()[623][624]

Description:

Connect to the HDFS file system and return an HDFS client object.

Syntax:

hdfs_client( xmlfile, …;url )

Note:

This external library function connects to the Hadoop server and returns an HDFS client object.

Parameters:

xmlfile	A Hadoop configuration file, like hdfs-site.xml, core-site.xml, mapred-site.xml and yarn-site.xml. Mulitple parameter files are separated by the comma; the parameter can be omitted. Users can do the configuration according to their needs. Support absolute paths only.
url	The URL format is scheme://authority/path. Scheme is the protocol name, which can be an ordinary file or an HDFS file; use an HDFS file name when accessing the HDFS file system and use an ordinary file name when accessing the local file system; authority is the host name; path is a string of the file (or directory) path.

Return value:

An HDFS client object

Example:

	A
1	=hdfs_client("D:/core-site.xml","D:/hdfs-site.xml";"hdfs://192.168.0.76:9000")	Connect to the HDFS; the Hadoop configuration files are saved in the root directory of D drive on the local machine; can do the configuration based on the actual needs
2	=hdfs_client(;"hdfs://192.168.0.8:9000")	Connect to the HDFS with the parameter xmlfile omitted

hdfs_close()[625][626]

Description:

Close the HDFS connection.

Syntax:

hdfs_close(HdfsClient)

Note:

This external library function closes a connection to the HDFS file system.

Parameters:

HdfsClient

An HDFS connection

Example:

	A
1	=hdfs_client(;"hdfs://192.168.0.8:9000")	Connect to the HDFS file system
2	=hdfs_close(A1)	Close the HDFS connection

hdfs_dir()[627][628]

Description:

Get the list of all files in a specified path.

Syntax:

hdfs_dir(hdfsfile, path)

Note:

This external library function lists names of all files in a specified path in an HDFS file system.

Parameters:

hdfsfile	An HDFS file object
path	A relative path within the path containing the HDFS file

Options:

@d	List names of all directories in the specified path
@p	List the full paths of all directories and files in the specified path
@m	Create a directory; return true if the directory is created, otherwise return false
@r	Delete a directory; return true if the operation is successful, otherwise return false

Return value:

A sequence or a boolean value

Example:

	A
1	=hdfs_client(;"hdfs://192.168.0.8:9000")	Connect to the HDFS file system
2	=hdfs_dir@p(A1,"/user")	List the full paths of all directories and files under the /user directory
3	=hdfs_dir@d(A1,"/user")	List names of all directories under the /user directory
4	=hdfs_dir(A1,"/user")	List all file names under the /dr1 directory
5	=hdfs_dir@m(A1,"/user/h1")	Create a directory named h1 under the /user directory
6	=hdfs_dir@r(A1,"/user/h1")	Delete the /user/h1 directory
7	=hdfs_close(A1)	Close the HDFS connection

hdfs_file()[629][630]

Description:

Open a specified directory and return an HDFS file flow.

Syntax:

hdfs_file(HdfsClient,file:cs )

Note:

The function returns an HDFS file flow. The file extension determines the compression method; support writing data in a stream style into a non-segmental file, but there is no such a restriction on reading data in.

Parameters:

HdfsClient	An HDFS Client object
file	The name of the to-be-loaded Hadoop file
cs	The charset embedded in JVM; by default it is the default value for a virtual machine

Return value:

A file object

Example:

	A
1	=hdfs_client(;"hdfs://192.168.0.8:9000")	Connect to the HDFS file system
2	=hdfs_file(A1,"/user/stu.txt":"GBK")	Read the HDFS file and return a file object
3	=A2.read@n()	Read the content of the file object as a string and return it
4	=A2.import@t()	Read the content of the file object as the records to form a table sequence and return it
5	=A2.cursor().fetch ()	Create a cursor based on a file object and fetch records from the cursor
6	=hdfs_close(A1)	Close the HDFS connection

hive_client()[631][632]

Description:

Create a Hive database connection.

Syntax:

hive_client(hdfsUrl,thriftUrl,dbname,hdfsUserName)

Note:

This external library function connects to a Hive database. The format of the parameter hdfsUrl is hdfs://ip:port, which represents the HDFS file’s IP and port number. The format of the parameter thriftUrl is thrift://ip:port, which represents the Thrift file’s IP and port number. The parameter dbname is database name. hdfsUserName is the user name for an HDFS file.

Parameters:

hdfsUrl	HDFS file connection information
thriftUrl	Thrift file connection information
dbname	A database name
hdfsUserName	HDFS file user name

Return value:

Cursor.

Example:

	A
1	=hive_client("hdfs://192.168.0.8:9000","thrift://192.168.0.8:9083","hive","asus")	Connect to the hive database

Related functions:

hive_close()

hive_cursor()

hive_query()

hive_close()[633][634]

Description:

Close a Hive database connection.

Syntax:

hive_close()

Note:

This external library function closes connection to a Hive database.

Example:

	A
1	=hive_client("hdfs://192.168.0.8:9000","thrift://192.168.0.8:9083","hive","asus")
2	=hive_close()	Close connection to the hive database

Related functions:

hive_cursor()

hive_query()

hive_cursor()[635][636]

Description:

Query a Hive database and return the result as a cursor.

Syntax:

hive_cursor(con,sql)

Note:

This external library function performs a SQL query and returns the result as a cursor. The parameter con is database connection.

Parameters:

con	Database connection string.
sql	A SQL query statement, like *select from tabl**e.

Return value:

Cursor

Example:

	A
1	=hive_client("hdfs://192.168.0.8:9000","thrift://192.168.0.8:9083","hive","asus")	Connect to the hive database
2	*=hive_cursor(A1, "select from table")**	Return a cursor
3	=hive_close()

Related functions:

hive_close()

hive_query()

hive_execute()[637][638]

Description:

Execute Hive’s SQL-like queries.

Syntax:

hive_execute(con,sql)

Note:

This external library function supports executing Hive’s SQL-like statements, including create table, drop table, load data, insert into, insert owerwrite, and create view. The statement Load data local inpath supports only operations on local files, rather than those on a Hive server; the statement Load data inpath supports operations on HDFS files, over which the user needs to have the corresponding privilege.

Parameters:

con	Database connection string
sql	A SQL query statement, which supports Hive’s SQL-like queries such as create table, drop table, load data, insert into, insert owerwrite, and create view

Return value:

A boolean value

Example:

	A
1	=hive_client("hdfs://192.168.0.8:9000/","thrift://192.168.0.8:9083","hive","asus")	Connect to the hive database
2	=hive_execute(A1, "create table stu2( id string, name string,age string)")	Create a table
3	=hive_execute(A1, "drop table stu")	Drop a table
4	=hive_execute(A1, "alter table stu2 add columns (ncol string)")	Add a column to the table
5	=hive_execute(A1, "insert into stu2 values ('2','dfff','21','lll')")	Insert data into the table
6	=hive_execute(A1,"load data local inpath 'D:\\haha.txt' overwrite into table ha")	Upload a local txt file to overwrite a Hive table

Related functions:

hive_query()[639][640]

Description:

Query a Hive database and return the result as a sequence.

Syntax:

hive_query(con,sql)

Note:

This external library function executes a certain SQL query on a Hive database, and returns the query result as a table sequence. The parameter con represents database connection.

Parameters:

con	Database connection string.
sql	A SQL query statement, like *select from tabl**e.

Return value:

Table sequence

Example:

	A
1	=hive_client("hdfs://192.168.0.8:9000","thrift://192.168.0.8:9083","hive","asus")	Connect to the hive database
2	*=hive_query(A1, "select from table")**	Query data in table
3	=hive_close()

Related functions:

hive_close()

hive_cursor()

hosts()[641][642]

Description:

Search the main processes to get nodes containing specified data zones.

Syntax:

hosts(h,n)

Note:

The function gets the nodes containing data zones from 1 to n from the sequence of main processes h and returns them by data zone numbers. When parameter n is 0, return all available nodes in h.

It performs the searching by node computing ability in descending order. For example, after finding the node containing data zone 1, the function assumes that the number of subtasks running on it is less than the preferred task number and re-assests the computing abilities of the other nodes to find the node holding data zone 2.

Parameters:

h	The sequence of main processes
n	Data zone number

Options:

@i	Find data zones numbered from 1 to n from the main processes and return them as a sequence. Use default hosts method to find if one or more data zones cannot be found; return null if the second searching fails.
@0	Find available nodes specified by parameter n without referencing the data zones; use this option at the second searching when it works with @i option.

Return value:

A sequence

Example:

hosts("192.168.0.116:8281",2)

hosts(["192.168.0.116:8281","192.168.0.116:8282"],0)

Parameter n is 0 and the function returns the available nodes

hosts(["192.168.0.116:8281","192.168.0.116:8282","192.168.0.129:8281"],3)

hour()[643][644]

Description:

Get the hour from a specified datetime.

Syntax:

hour(datetimeExp)

Note:

Get the hour from the specified time datetimeExp.

Parameters:

datetimeExp

Date or standard datetime format string

Return value:

Integer

Example:

hour("1983-12-15")	0
hour("1983-12-15 10:30:25")	10
hour(datetime("2006-01-15 13:20:30"))	13

Related functions:

year()

month()

day()

minute()

second()

htmlparse()^{^[645]}^{^[646]}

Description:

Get text data under a specified tag in an html file.

Syntax:

s.htmlparse(tag:i:j,…)

Note:

The function gets the j^th text file under the i^th tag from html file s. Get all data in the html file when there aren’t parameters.

Parameters:

s	Content of an html file
tag	A tag in an html file; if the tag’s value is “table”, get all data under it
i	An integer
j	An integer

Return value:

A sequence

Example:

	A
1	=file("D:/test.html").read()	Read the content of an html file
2	=A1.htmlparse("a":11:0)	Get the 1^st text file under the 12^th <a> from A1’s html file
3	=A1.htmlparse("a":11:0, "span":8:0)	Get text files under two tags from A1’s html file
4	=A1.htmlparse("table":7)	Get all content under the 8^th <table>

httpfile()[647][648]

Description:

Package the returned result of URL as the file flow and return it.

Syntax:

httpfile(url:cs,post:cs;header)

Note:

The function packages the returned result of URL string of HTTP service into a file flow and returns it, which can only be retrieved with segmentation forbidden.

Parameters:

url

HTTP service in the URL string format.

The parameter port is the port number configured in Http Server. The dfx path is the one relative to the main directory configured in Tool -> Options -> Environment.

Two scenarios about the syntax of writing a URL for performing an HTTP service:

I. esProc style

Here are the syntax of writing a URL when using esProc’s HTTP service:

http:// IP:port /dfx1.dfx()

http:// IP:port /dfx1.dfx(arg1,arg2,...)

http://IP: port/dfx1.dfx(...)dfx2.dfx

http://[IP6]:port /dfx1.dfx()

1. There’s only one dfx file. If the dfx file has parameters, write them in order in the parentheses after the file; use comma to separate the multiple parameters. If the dfx file hasn’t parameters, the parentheses are empty; in this case the format of the file’s return value is what a user expects.

2. There are two dfx files. When the return value format a user wants is different from the format of the return value in dfx1 file, dfx2 file is used to change the format of the return value in dfx1 into a desired one. The syntax for dfx1 is the same as the that for the dfx file in the first scenario, but here the file supports only the single result set. dfx2 file is a program with only one parameter, which is the return value of dfx1 file.

dfx2 file converts the format of the return value in dfx1 file into a desired one and return it as a result. For example, in the table sequence returned by dfx1 file, fields are by default separated by “|”; you can change dfx1’s return value in dfx2 to use the blank space as the separator.

If the second result set, which must contain strings, is returned, it is treated as the header.

3. For IPv6, bracket the IP address with [].

II. SAP style

http://IP:port /sapPath/dfx No parameters

http://IP:port /sapPath/dfx/arg1/arg2,... Use the slash sign (/) to separate the parameters

sapPath is relative to the dfx file’s main director; it can be a multilevel directory structure or an empty string. sapPath should be configured in [installation directory]/config/httpServer.xml. A sapPath can contain multiple paths which sparated by comma. dfx represents a dfx file’s name, which doesn’t have an extension. arg contains both the name and value; the name consists of all letters and the value always begins with a number.

Note:To access database data from the dfx file, configure the value of autoConnect property as true in raqsoftconfig.xml’s DB node; you can’t connect to the database if skipping this configuration.

Character set, which supports JVM's built-in character set, and which by default is the default value of virtual machine.

post

header

A parameter submitted with POST method with a syntax like p₁=v₁&p₂=v₂…. Can be omitted.

The header property can have multiple items, like headerName1:value1,headerName2:value2,... (the format is "property":"value",…); or can be omitted. The execution of .property() function over a returned file object will return the header property.

Return value:

File flow

Example:

	A
1	=httpfile("http:// localhost:9090/p1.dfx()":"GBK").import@t()	Here’s the p1.dfx file: Load p1.dfx file from the http server, with the charset as GBK
2	=httpfile("http://localhost:9090/p2.dfx(3)":"GBK").import@t()	Here’s the p2.dfx file where StuId is the parameter 3 is the value of parameter in p2.dfx file
3	=httpfile("http://localhost:9090/p3.dfx(3，Class%20two)":"GBK").import@t()	Here’s the p3.dfx file where StuId and Class are the parameters The two parameters are separated by a comma
4	=httpfile("http://localhost:9090/http2.dfx(30)").import@t()	Here’s the http2.dfx where id is the parameters
5	=httpfile("http://127.0.0.1:9090/http2.dfx(30)http3.dfx").import@t()	Here’s the http3.dfx Process the return value of http2.dfx in http3.dfx
6	=httpfile("http:// 192.168.0.131:6080/myweb/servlet/testServlet?table=employee&type=json")	testServlet returns a string of employee data in the JSON format
7	=httpfile("http://localhost:6080/myweb/servlet/testServlet":"GBK","table=employee&type=json":"GBK")
8	=httpfile("http://127.0.0.1:8182/scada/v1/uaes/datapoint/history/rawvalue/rtdb/access","{\"nodeIds\":[\"ns=102;s=AI_002_0600.PV\"], \"startTime\":\"2018/6/28 13:10:00\", \"endTime\":\"2018/6/28 13:11:0\", \"returnBounds\":\"false\", \"maxSizePerNode\":\"10\"}"; "Content-Type":"application/json")
9	=httpfile("http://192.168.74.1:8508/sap/arg/arg22").read()	Sap style; configure the style in [installation directory]/config/httpServer.xml; here sapPath is "/sap"; it can contain multiple values that separated by comma, like sapPath="/sap,/sap/en". The dfx file name doesn’t have an extension and the name and value of a parameter are written continuously
10	=httpfile("http://192.168.74.1:8508/arg/arg22").read()	There’s no need to configure sap if the file is under the main directory; and the port number can be directly followed by /dfx
11	httpfile("http://[fe80::2918:abe0:3017:8401%15]:8503/emp.dfx()":"GBK").import@t()	Load emp.dfx file through http service via IPv6 connectivity using GBK charset

icursor()[649][650]

Here’s how to use icursor() functions.

T.icursor()^{^[651]}^{^[652]}

Description:

Use index to filter an entity table according to the filtering condition.

Syntax:

T.icursor(C,…;w,I)

Note:

The function filters entity table T according to filtering condition w using index I and returns an ordinary cursor; automatically get the index if parameter I is absent.

Parameters:

T	An entity table
C	To-be-retrieved columns in the entity table; get all columns when the parameter is absent
w	Filtering condition, in which the filtering field for T must be the same as the indexing field
I	Index name; can be omitted

Options:

@s	Make sure the result set is ordered by the index and large result sets are supported; the option supports an entity table generated from a file group
@u	Handle multiple conditions joined up with && from left to right while the default is handling them in an optimal order

Return value:

A single-thread cursor

Example:

	A
1	=file("D:\\emp1.ctx")
2	=A1.create(#EID,NAME;EID)	Create a composite table where EID field is the key by which records are segmented
3	=demo.cursor("select EID,NAME from employee where EID< 10")
4	=A2.append(A3)
5	=A2.attach(table1,DEPT,GENDER)	Add an attached table to the base table
6	=demo.cursor("select EID,DEPT,GENDER from employee where EID< 10")
7	=A5.append(A6)	Append cursor records to the attached table
8	=A7.index(test_index,GENDER=="F";DEPT;)	Create an index named test_index
9	=A7.icursor(;DEPT=="HR",test_index)	Use index test_index to get all columns where DEPT is HR from entity table table1 and return the result as a cursor
10	=A9.fetch()	Fetch data from the cursor

T.icursor()^{^[653]}^{^[654]}

Description:

Use index to filter a cluster table according to the filtering condition.

Syntax:

T.icursor(C,…;w,I)

Note:

The function filters cluster table T according to filtering condition w using index I; automatically get the index if parameter I is absent.

Parameters:

T	A cluster table
C	To-be-retrieved columns in the cluster table; get all columns when the parameter is absent
w	Filtering condition, in which the filtering field for T must be the same as the indexing field
I	Index name; can be omitted

Options:

@s Make the result set ordered by the index and support a big result set

Return value:

A cluster cursor

Example:

	A
1	=file@z("emp1.ctx","192.168.0.101:8281")	Open a cluster file
2	=A1.create()	Create a cluster table
3	=A2.attach(table1)	Retrieve cluster table table1
4	=A3.index(test_index2,GENDER=="F";DEPT;)	Create index file test_index2
5	=A3.icursor(;DEPT=="HR",test_index2)	Use index test_index2 to get all columns in A3’s cluster table where DEPT is HR and return the result as a cluster cursor
6	=A5.fetch()
7	=A2.index(test_index1,EID<16;NAME;)	Create index file test_index1
8	=A2.icursor(EID,SURNAME;NAME=="Smith",test_index1)	Use index test_index1 to get EID column and SURNAME column in A2’s cluster table where NAME is SMITH and return the result as a cluster cursor
9	=A8.fetch()

icount()^{^[655]}^{^[656]}

Here’s how to use icount() function.

A.icount()^{^[657]}^{^[658]}

Description:

Count the number of distinct members in a sequence.

Syntax:

A.icount()

Note:

The function calculates the number of distinct members in a sequence A.

Parameters:

A	A sequence of n members

Options:

@o Remove duplicates by comparing neighboring members

Return value:

A numerical value

Example:

	A
1	=["a","c","d","e","f","a","a"]
2	=A1.icount()	5
3	=A1.icount@o()	6

id()[659][660]

Here’s how to use id() function.

A.id()[661][662]

Description:

Get distinct values from a sequence.

Syntax:

A.id(x_i,…;n)

Note:

The function gets top n distinct values of the expressions x_i,…. If the number of distinct values in an expression x is less than n, return all distinct values as a sequence; the result set consists of one ordinary sequence when there is only one expression x.

Parameters:

xi	An expression; use ~ to represent x if the latter is omitted
n	The number of to-be-retrieved distinct values counting from the beginning; return all values if it is absent

Options:

@o	Without sorting, remove the neighboring duplicate members only
@u	Do not sort the result set by x; it doesn’t work with @o
@h	Used over a grouped table with each group ordered to speed up grouping

Return value:

The new sequence composed of the distinct values of x

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1.id(DEPT)	Sort members in ascending order
3	=A1.id@o(DEPT)	No sorting
4	=A1.id([DEPT,GENDER])	Get the distinct values after sorting by DEPT & GENDER
5	=["a","b","c","a"].id()	Omitting x indicates it is the sequence members themselves that will be computed to get the distinct values. Return ["a","b","c"] as with this case
6	=A1.id@u([DEPT,GENDER])	Do not sort the result set by x
7	=A1.id(DEPT,GENDER)	Return all distinct values as parameter n is absent
8	=A1.id(DEPT,GENDER;4)	Return the first 4 distinct values; return all GENDER values as the field has less than 4 distinct values
9	=file("D:/emp10.txt").import@t()	For data file emp10.txt, every 10 records are ordered by DEPT
10	=A9.id@h(DEPT)	As A19 is grouped and ordered by DEPT, @h option is used to speed up grouping

Related functions:

A. group(xi,…)

ch.id()[663][664]

Description:

Generate a channel consisting of values of one or more fields.

Syntax:

ch.id(x_i,…;n)

Note:

The function generates a channel containing a sequence of sequences, each of which is made up of values of x_ifield in channel ch. Get at most n values for each x_ifield; return a channel containing one sequence when there is only one x_ifield. It is for getting the result set from the channel.

Parameters:

ch	Channel
x_i	Expression; use comma to separate multiple expressions
n	Integer; can’t be omitted

Return value:

Channel

Example:

	A
1	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE")
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A2.id(#1,DEPT;10)
5	=A3.id(DEPT;5)
6	=A1.push(A2,A3)	Push data in A1’s cursor into A2’s channel and A3’s channel
7	=A1.fetch()
8	=A2.result()
9	=A3.result()

cs.id()[665][666]

Description:

Generate a sequence consisting of values of fields in a given cursor.

Syntax:

cs.id(x_i,…;n)

Note:

The function generates a sequence of sequences, each of which is made up of values of x_ifield in cursor cs. Get at most n values for each x_ifield; return a sequence when there is only one x_ifield.

Parameters:

cs	Cursor
x_i	Expression; use comma to separate multiple expressions
n	Integer; return all values when omitted

Return value:

Sequence

Example:

	A
1	*=demo.cursor("select from EMPLOYEE" )**
2	=A1.id(#1,DEPT;5)
3	*=demo.cursor("select from EMPLOYEE" )**
4	=A3.id(DEPT;5)

if[667][668]

Here’s how to use if statment.

if x[669][670]

Description:

The introduction of if statement.

Syntax:

if x

Note:

The statement executes the if code block if x is true and skip if code block if x is false.

Parameters:

x	A boolean expression. If the value is true, then execute if code block. Otherwise, skip it.

Example:

	A	B
1	=6		16
2	if A1>5		if code block
3		>A1=A1+10	if code block

Related functions:

if x …{ else { if x}… }

if x … else …

if x else

if x …{ else { if x}… }[671][672]

Description:

The introduction of if statement.

Syntax:

if x

… The if code block

{else {if x}}

… The else or else if code block. When else or else if is not found, then else or else if code block does not exist.

Note:

If the conditional expression x is evaluated as true, then execute the if code block, otherwise, skip the if code block and execute the code block of else or else if.

Parameters:

x	A boolean expression. If the result is true, then execute if code block, otherwise, execute the else or else if code block, if any. If no else or else if code block is available, then the if statement terminates.

Example:

	A	B	C
1	=13	=2		C1 returns 7
2	if(A1>10)
3		if(B1==1)	>C1=2+3
4		else if(B1==2)	>C1=3+4
5		else if(B1==3)	>C1=4+5
6	else if(A1>5)
7		>C1=5+6

Related functions:

if x … else …

if x else

if x

if x…else …[673][674]

Description:

The introduction of if statement.

Syntax:

if x … else …

Note:

if and else are in the same line. If x is true, then execute the code between if and else; if x is false, execute the code after else till the end of this line. The else… part can be omitted.

Parameters:

x	A boolean expression

Example:

	A	B	C	D
1	=2				A1 returns 7
2	if A1>5	>A1=A1+4	else	>A1=A1+5

Related functions:

if x …{ else { if x}… }

if x else

if x

if x else[675][676]

Description:

The introduction of if statement.

Syntax:

if x

…

else

…

Note:

if and else must be in the same column. Execute if code block if x is true and execute else code block if x is false. The else part can be omitted.

Parameters:

x	A boolean expression. If evaluated to be true, then execute if code block, otherwise, execute else code block.

Example:

	A	B
1	=3
2	if A1>5		if code block
3		>A1=A1+10	if code block
4	else		else code block
5		>A1=A1+15	else code block

Related functions:

if x …{ else { if x}… }

if x … else …

if x

if()[677][678]

Description:

Calculate boolean expressions from left to right. if the result is true, return true value; otherwise return default value or false value.

Syntax:

if(a)	If a is true, then return true. Otherwise, return false
if(a,b,c)	If a is non-null and non-false, then return b; otherwise return c, which is null by default.
if(x1:y1,…,xk:yk;y)	Equivalent to if(x1,y1,if(x2,y2,…,if(xk,yk,y)))

Note:

This function calculates from left to right, and returns different values based on the different results of computing the boolean expressions. Return the corresponding result for the first expression whose value is trure and ignore other boolean expressions. If none of the boolean expression has true value, but there is a default value expression, then return the default value; if there is no such a default value expression, return null.

Parameters:

a	Boolean expression
b	Value expression. If the result of a is true, then return the result of b
c	Value expresssion. If the result of a is false, then return the result of c
xk	Boolean expression
yk	Value expression. If the result of xk is true, then return its result.
y	Default value expression. If all the results of boolean expressions are false, then return the result of this expression.

Return value:

The data type is dynamic, and is determined by the result of value expression. If the corresponding value expression is absent, then return null.

Example:

	A
1	=if(2>1,"Truth","Fallacy")	Truth
2	=85
3	=if(A2>90:"Excellent",A2>80:"Good",A2>60:"Passed","Failed")	Good
4	>A2=300
5	=if(A2>100:,A2>90:"Excellent",A2>80:"Good",A2>60:"Passed","Failed")	null
6	=if(A2>100)	true

Related functions:

case()

between()

ifa()[679][680]

Description:

Find whether an object is a sequence.

Syntax:

ifa(x)

Note:

The function finds whether the parameter x is a sequence.

Parameters:

x	The object to be judged

Return value:

A boolean value

Example:

	A
1	=ifa([1,2,3])	True
2	=ifa(123)	False

Related functions:

ift()

ifr()

ifv()

ifdate()[681][682]

Description:

Find whether the type of parameter is date or datetime.

Syntax:

ifdate(exp)

Note:

The function finds whether the type of parameter exp is date or datetime.

Parameters:

exp	Expression of any data type

Return value:

Boolean value

Example:

ifdate("2006-10-10")	false
ifdate(date("2006-10-10"))	true
ifdate(date("2006-10-10 10:20:30"))	true
ifdate("20061010")	false
ifdate("10:20:30")	false

Related functions:

iftime()

ifn()[683][684]

Here’s how to use ifn() function.

A.ifn()[685][686]

Description:

Get the first non-null member of a sequence.

Syntax:

A.ifn()

Equivalent to ifn(x₁,…,x_n)

Note:

The function gets the first non-null member of sequence A.

Parameter:

A	A sequence with the length of n

Return value:

The first non-null member of the sequence.

Example:

	A
1	=[1,2,4].ifn()	1
2	=[null,2,3,4].ifn()	2
3	=[null,2,null,4].ifn()	2
4	=ifn(null,1,2,4)	1

Related functions:

A.ifn(x)

A.ifn(x)[687][688]

Description:

Compute x with each member of the sequence and return the first non-null member of the new sequence.

Syntax:

A.ifn(x)

Equivalent to A.(x).ifn()

Note:

The function loops through members of sequence A to compute expression x and return the first non-null member of the new sequence.

Parameters:

A	A sequence
x	Generally an expression of a single field name, or a legal expression composed of multiple field names

Return value:

The first non-null member of the new sequence

Example:

	A
1	*=demo.query("select from EMPLOYEE")**
2	=A1.ifn(SALARY)	Return the first non-null value of SALARY
3	=A1.(SALARY+100).ifn()	Add 100 to the salary of each employee and return the salary of the first employee

Related functions:

A.ifn()

ifnumber()[689][690]

Description:

Find whether the parameter is of numeric data type.

Syntax:

ifnumber( Exp )

Note:

The function finds whether the parameter Exp is of numeric data type.

Parameters:

Exp	Expression of any data type

Return value:

Boolean value

Example:

ifnumber("abc")	false
ifnumber("1234")	false
ifnumber(1234)	true
ifnumber("1234sss")	false

Related functions:

ifstring()

ifr()[691][692]

Description:

Find whether an object is a record.

Syntax:

ifr(x)

Note:

The function finds whether the parameter x is a record.

Parameter:

x	Any data object, for example a constant, an expression, a record, a record sequence, a sequence or a table sequence.

Return value:

true/false

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=ifr(A1(1))	true
3	=ifr(A1)	false
4	=ifr(A1(1).BIRTHDAY)	false

Related functions:

ift()

ifa()

ifv()

ifstring()[693][694]

Description:

Find whether the parameter is of string data type.

Syntax:

ifstring(Exp)

Note:

The function finds whether the parameter Exp is of string type.

Parameter:

Exp	Expression of any data type

Return value:

Boolean value

Example:

ifstring("abc")	true
ifstring(1234)	false
ifstring("1980-01-01")	true
ifstring(date("1980-01-01"))	false

Related functions:

ifnumber()

ift()[695][696]

Description:

Find whether an object is a table sequence.

Syntax:

ift(x)

Note:

The function finds whether the parameter x is a table sequence.

Parameter:

x	Any object, for example a constant, an expression, a record, a record sequence, a sequence or a table sequence.

Return value:

true/false

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=ift(A1(1))	false
3	=ift(A1)	true
4	=ift([1,2,3])	false

Related functions:

ifr()

ifa()

ifv()

iftime()^{^[697]}^{^[698]}

Description:

Find whether the parameter is of time data type.

Syntax:

iftime(exp)

Note:

The function finds whether the parameter exp is of time type.

Parameter:

exp	Expression of any data type

Return value:

Boolean value

Example:

iftime("10:20:30")	false
iftime(time("10:20:30"))	true
iftime("2006-10-10")	false
iftime("2006-10-10 10:20:30")	false
iftime("20061010")	false

Related functions:

ifdate()

ifv()[699][700]

Description:

Check whether a variable exists.

Syntax:

ifv(v)

Note:

This function is mainly used to find if any variable is added to the current execution environment by the external program when the external program calls the program cellset. Generally, there is no need to check the defined variable in the cellset script. They are there for sure if you've defined them.

Parameters:

v	Parameter name

Return value:

Boolean value

Example:

	A
1	>arg1=1
2	=ifv(arg1)	true

Related functions:

ift()

ifa()

ifr()

ifx_close()[701][702]

Description:

Close Informix database connection.

Syntax:

ifx_close(ifxconn)

Note:

The function closes connection to Informix database.

Parameter:

ifxconn

Ifxconn object

Example:

	A
1	="d:/frag.txt"	A fragmentation information file
2	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli://192.168.0.3:9088/tpch:informixserver=tpch&user=informix&pwd=informix";A1)	Connect to Informix database and get the fragmentation information via a file handle
3	=ifx_close(A2)	Close Informix database connection

ifx_conn()[703][704]

Description:

Create Informix database connection.

Syntax:

ifx_conn(url; fragfile)

ifx_conn(driver,url; fragfile)

Note:

The function connects to the external Informix database. The format of the parameter url is the same as that of the JDBC URL.

Parameter:

driver	Name of JDBC driver for connecting to Informix database; the format is com.informix.jdbc.IfxDriver
url	The URL to connect to Informix server
fragfile	Fragmentation information file that records the fields and every field’s max and min values in each fragmented file

Return value:

Ifxconn object

Example:

	A
1	="d:/frag.txt"	A fragmentation information file
2	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli://192.168.0.3:9088/tpch:informixserver=tpch&user=informix&pwd=informix";A1)	Connect to Informix database and get the fragmentation information as a file handle
3	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli://192.168.0.3:9088/tpch:informixserver=tpch&user=informix&pwd=informix";"d:/frag.txt")	Connect to Informix database and get the fragmentation information as a file

ifx_cursor()[705][706]

Description:

List the fragmentation information of a specified table with cursors.

Syntax:

ifx_cursor(ifxconn, sql; k1:k2)	Query data in fragmented files from k1 to k2 using a SQL statement
ifx_cursor(ifxconn, table:where, f:alias,...; k1:k2)		List the fragmentation information of table table with cursors and search fragmented file k1 and fragmented file k2 according to the where condition. Parameter f is the table’s column name and parameter alias is the column’s another name. Parameter where can be omitted; parameter k2 will be omitted if parameter k1 is absent; search only framted file k1 when k2 is absent
ifx_cursor(ifxconn, sql; ifxCursor:f2)		Query data over the fragmented file specified by the parameter ifxCursor quries with a SQL statement; parameter f2 is the fragmented field, which, if absent, is the fragmented field of the fragmented file ifxCursor
ifx_ cursor(ifxconn, table:where, f:alias,...; ifxCursor:f2)		Query table table according to where condition over the fragmented file specified by parameter ifxCursor; parameter f is the table’s column name and parameter alias is its another name; f2 is the fragmented field, which, if absent, is the fragmented field of the fragmented file ifxCursor

Parameters:

ifxconn	Ifxconn object
sql	A SQL statement
table	A table being fragmented
where	Query condition; can be omitted
f	A column name of a fragmented file
alias	Another name of column f
k1	A fragmented file; can be omitted
k2	A fragmented file; can be omitted
ifxCursor	The fragmented file recorded with cursor
f2	A fragmented field; can be omitted

Options:

@o	Allow unordered data
@f	Require data to be ordered
@m	Enable the use of multiple channels

Return value:

Cursor

Example:

	A
1	=ifx_conn("jdbc:informix-sqli:192.168.0.3:9088/tpch:;DB_LOCALE=en_us.819;CLIENT_LOCALE=en_us.57372;NEWCODESET=GBK,8859-1,819;informixserver=tpch&user=informix&pwd=informix";"frag.txt")	Connect to Informix database
2	=ifx_takefrag(A1)
3	=ifx_cursor(A1,"select L_ORDERKEY,L_RETURNFLAG,L_LINESTATUS,L_QUANTITY,L_EXTENDEDPRICE,L_DISCOUNT,L_TAX from lineitem";2:3)	Query data in the 2^nd and the 3^rd fragmented files through a SQL statement
4	=A3.fetch(10000)
5	=ifx_cursor@o(A1,"lineitem":"L_LINESTATUS='F'","L_TAX":"tax",L_LINESTATUS;2:3)	Query the 2^nd and the 3^rd fragmented files of table lineitem according to condition L_LINESTATUS='F'; with @o option used, get column L_TAX, whose alias is tax, and column L_linestatus in an unordered way
6	=A5.fetch(10000)
7	=ifx_cursor@o(A1,"select skip 0 first 30000 L_ORDERKEY,L_RETURNFLAG,L_LINESTATUS,L_QUANTITY,L_EXTENDEDPRICE,L_DISCOUNT,L_TAX from lineitem";A3:"l_orderkey")	Query the same fragmented file as that in A3 through a SQL statement, with the fragmented field as l_orderkey, which can be omitted because it is the same as that of A3’s fragmented file
8	=A7.fetch(10000)
9	=ifx_cursor@o(A1,"lineitem":"L_LINESTATUS='F'","L_TAX":"tax",L_LINESTATUS; A5:"l_orderkey")	With @o option used, get column L_TAX, whose alias is tax, from one of the fragmented file of table lineitem, which is the same as A5’s fragmented file, and column L_LINESTATUS, according to condition L_LINESTATUS='F' in an unordered way; the fragmented field is l_orderkey, which can be omitted because it is the same as that of A5’s fragmented file
10	=A9.fetch(10000)

ifx_listfrag()[707][708]

Description:

List the fragmentation information of a specified table with table sequences.

Syntax:

ifx_listfrag(ifxconn, table)

Note:

The function lists the fragmentation information of a specified table with table sequences on the condition that the fragmentation information is already written into the ifxconn object. List the fragmentation information all fragmented table being fragmented if parameter table is absent.

Parameters:

ifxconn	The ifxconn object which holds the fragmentation information
table	A table being fragmented

Return value:

A table sequence

Example:

	A
1	="d:/frag1.txt"	Create and save a fragmentation information file
2	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli:192.168.0.7:8000/tpch:informixserver=tramsserver&user=informix&pwd=informix";A1)	Connect to Informix database
3	=ifx_takefrag(A2)	Extract the fragmentation information of all specified tables
4	=ifx_listfrag(A2)	List the fragmentation information of all specified tables
5	= ifx_listfrag(A2,"orders")	List fragmentation information of the orders table

ifx_savefrag()[709][710]

Description:

Save the fragmentation information file stored in the memory as a new file.

Syntax:

ifx_savefrag(ifxconn, file)

Note:

The function saves the fragmentation information stored in the memory as a new file. The new file can be the same as the file fragfile created via ifx_conn(), or one saved in another name.

Parameters:

ifxconn	An ifxconn object
file	A fragmentation information file, which can be the same file as fragfile or not.

Return value:

Table sequence

Example:

	A
1	="d:/frag1.txt"	Create and save a fragmentation information file
2	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli:192.168.0.7:8000/tpch:informixserver=tramsserver&user=informix&pwd=informix";A1)	Connect to Informix database
3	=ifx_takefrag(A2)	Extract the fragmentation information of all specified tables
4	=ifx_savefrag(A2,A1)	Save the fragmentation information stored in the memory as the file frag1.txt
5	=ifx_savefrag(A2,"d:/frag2.txt")	Save the fragmentation information stored in the memory as another file frag2.txt

ifx_setfrag()[711][712]

Description:

Set the fragmentation information of a specified table.

Syntax:

ifx_setfrag (ifxconn, table, fieldName, min1, min2,....)

Note:

The function sets the fragmentation information of the specified table. If the parameters after parameter fieldname are absent, then delete the specified table’s fragmentation information stored in the IfxConn object. The the number of the values of parameter min is the number of fragmented files the specified table has.

Parameters:

ifxconn	An ifxconn object
table	A table being fragmented
fieldName	Fragmented field
min	The minimum value in a fragmented file; can be omitted and can have multiple values

Return value:

Table sequence/null

Example:

	A
1	="d:/frag1.txt"	Create and save a fragmentation information file
2	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli:192.168.0.7:8000/tpch:informixserver=tramsserver&user=informix&pwd=informix";A1)	Connect to Informix database
3	=ifx_takefrag(A2,"orders")	Extract fragmentation information of the orders table
4	=ifx_setfrag(A2,"orders","o_orderkey",1,400000000)	Set fragmentation information of the orders table
5	=ifx_setfrag(A2,"orders","o_orderkey")	Delete the fragmentation information

ifx_takefrag()[713][714]

Description:

Extract fragmentation information from the database.

Syntax:

ifx_takefrag(ifxconn, table1,table2,...)

Note:

The function extracts the fragmentation information of the specified table(s) from the database and writes it into the Ifxconn object. As there isn’t the fragmentation information in fragfile file, the txt file is empty; get the fragmentation file of all tables being fragmented if parameter table is absent.

Parameters:

ifxconn	An Ifxconn object
table	The table being fragmented; can be omitted and can have multiple number of it

Example:

	A
1	="d:/frag1.txt"	Create and save a fragmentation information file
2	=ifx_conn("com.informix.jdbc.IfxDriver","jdbc:informix-sqli:192.168.0.7:8000/tpch:informixserver=tramsserver&user=informix&pwd=informix";A1)	Connect to Informix database
3	=ifx_takefrag(A2)	Extract fragmentation information of all specified tables
4	=ifx_takefrag(A2,"lineitem")	Extract fragmentation information of table lineitem

import()[715][716]

Here’s how to use import() function.

S.import()[717][718]

Description:

Retrieve contents from strings as records and return them as a table sequence.

Syntax:

S.import(F_i:type;fmt,…;s)

Note:

The function retrieves specified or all fields from string S and returns them as a table sequence.

Parameters:

S	The string. Its format: separate the records by line break, and the fields by user-defined separator; the default separator is tab.
F_i	Fields to be retrieved; by default all fields will be retrieved.
type	Field types include bool, int, long, float, decimal, number, string, date, time and datetime; data type of the first row will be used by default. It is the length of a serial byte when it is an integer.
fmt	Date\time format
s	User-defined separator; the default is tab.

Options:

@t	Take the first row in f as the field name. If not using this option, then use _1, and _2,… as the field name.
@c	Use comma as the separator when the parameter s is absent, but the user-defined separator s should take priority when there are both s and @c option.
@j	Import records from json strings and resolve them into a table sequence, with s being ignored. Of [{F:v,…},…], v is the value of F; it will be quoted when being the string constant, and represented reclusively when it is a sequence or a table sequence.
@x	Retrieve data from strings of XML format as multi-level records or a table sequence (similar to retrieving data from json strings). The identifier within <> is the field name; identifiers with the same name indicate that a table sequence will be generated; ignore the non-identifier properties within <>. <xml> <table> <row> <F>v</F> … </row> … </table> </xml> s is the level separator; slash / is used to separate the level of data to be retrieved and its superior level; when omitted data will be retrieved from the root level.
@s	Won’t split strings and data will be imported as a table sequence consisting of strings of single field values; ignor the parameters
@i	Return the result set as a sequence if it only contains one field
@q	First remove quotation marks surrounding strings, including the headers, and then handle the escaping
@o	Use quotation marks as the escape character
@k	Retain the whitespaces on both sides of the data item; without it a trim operation will be automatically performed
@e	Generate null if parameter Fi isn’t included in the imported strings; by default there will be an error report
@d	Delete a record if it contains unmatching data types or data formats and start examining data by type
@n	Ignore a row whose number of columns don’t match the first row
@v	In corporation with @d or @n, if a mismatch appears, throw an exception, terminate the execution and output the content of the problem record

Return value:

Table sequence

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1.(~.array().concat@c())	Convert to the sequence of strings.
3	=A2(1).import(;",")	Select all fields from a specified string in the sequence. Specify comma as the separator, and return a table sequence as the result
4	=demo.query("select EID,NAME,SURNAME from EMPLOYEE")
5	=A4.export()
6	=A4.export@t(EID:id,NAME:name,SURNAME:surname;"\|")
7	=A5.import()	No parameters are given. The default separator will be tab, and _1 and _2,… will be used as field names
8	=A6.import@t(id:int,name;"\|")	Select fields id and name, separated by “\|”
9	="{name:'China',province:[{name:'Heilongjiang',cities: {city:['Harbin','Daqing']}},{name:'Guangdong', cities:{city:['Guangzhou','Shenzhen','Zhuhai']}},{name:'Taiwan',cities: {city:['Taipei','Kaohsiung']}},{name:'Xinjiang', cities:{city:['Urumqi']}}]}".import@j()	Parse JSON strings to get a table sequence - [{F:v,…},…], where v is the value of F field; write v recursively if it is a sequence or table sequence
10	=A4.export@j()
11	=A10.import@j()
12	=A4.export@x(;"employee/name")
13	=A12.import@x(EID;"employee/name")	Retrieve EID field of the name level.
14	=A2(1).import@c()	With @c option, use default separator commma
15	=A5.import@s()	With @s option, won’t split strings and records are imported as a single-field table sequence
16	=A5.import@si()	A single-field result set will be returned as a sequence
17	=["12\r34","aa\nbb"].export@q()
18	=A17.import()
19	=A17.import@q()	With @q option, double quotations will be removed before generating the final table sequence
20	=["12\r34","aa\nbb"].export@qo()
21	=A20.import@qo()	With @o option, use double quotations as escape character
22	=" abc ".import@k()	Retain the whitespaces on boths sides
23	=A6.import@te(id:int,name,dept;"\|")	Generate null since dept doesn’t exist in the imported strings
24	id\|name\|surname a\|Rebecca\|Moore 2\|Ashley\|Wilson 3\|Rachel\|Johnson 4\|Emily\|Smith 5\|Ashley\|Smith 6\|Matthew\|Johnson 7\|Alexis\|Smith 8\|Megan\|Wilson
25	=A24.import@td(id:int,name;"\|")	Delete the record as it contains unmatching data types
26	=A24.import@tv(id:int,name;"\|")	Check data type matching, and, if error reports, throw an exception, terminate the execution and output the content of the problem record; the error message is: Error in cell A26
27	id\|name\|surname 1\|Rebecca\|Moore 2\|Ashley 3\|Rachel\|Johnson 4\|Emily
28	=A27.import@tdn(id:int,name,surname;"\|")	Ignore row 2 and row 3 because the number of columns don’t match that of the table sequence

Related functions:

f.import()

A.export()

f.import()[719][720]

Description:

Read contents from a file and return them as a table sequence.

Syntax:

f.import()
f.import(F_i:type:fmt,…;k:n,s)	Retrieve the k^th segment of the n segments from the text file. F_i represents the retrieved field; all fields will be retrieved by default. s is the user-defined separator; the default is tab. When retrieving a file segment by segment, it intelligently identifies the ending points to ensure the retrieved records in each segment are complete and all retrieved records are continuous and unique

Note:

The function retrieves file f and returns a table sequence where each record consists of a line of f.

Parameters:

f	A file
F_i	Fields to be retrieved. All fields will be retrieved by default. The sign # is used to represent a field with a sequence number.
type	Field types include bool, int, long, float, decimal, string, date, time and datetime. Data type of the first row will be used by default. It is the length of a serial byte when it is an integer.
fmt	Date\time format
s	User-defined separator. The default separator is tab. When the parameter is omitted, the comma preceding it can be omitted, too.
k	The segment number.
n	The number of segments. Retrieve the whole file when both k and n are omitted.

Options:

@t	Use the first row of f as the field name. If this option is not used, _1, _2,… will be used as field names; keep the original field names if F_i is #i
@b	Retrieve data from the exported binary file, with the support for parameter F_i, k and n, and with no support available forparameters type and s. Options @t, @s, @i, @q and @m will be ignored. The segmental retrieval could result in empty segment in cases when a file has only a very small number of records or it is unable to be segmented.
@e	Make the function return null when F_idoesn’t exist in the file; raise an error when the option is absent.
@s	Do not split the to-be-retrieved field when it is imported as a cursor whose content is a table sequence consisting of strings of a single field; in this case the parameters will be ignored.
@i	If the result set has only one column, return it as a sequence
@q	Remove the quotation marks, if any, of the field strings, including the field names, in the first place, and handle the escape sequences.
@m	Use multithreads to increase data retrieval speed, but this will leave an indefinite order for members of the result set. This option will be ignored when parameters k and n exist and it is often used to retrieve data from big files. More than one parallel thread should be specified in license file and configuration information.
@c	Use comma as the seperator when the parameter s is absent, but the user-defined separator s should take priority when there are both s and @c option.
@o	Use quotation marks as the escape character
@k	Retain the whitespaces on both sides of the data item; without it a trim operation will be automatically performed
@d	Delete a record if it contains unmatching data types or data formats and start examining data by type
@n	Ignore and discard rows whose number of columns don’t match the first row
@v	Verify data type matching, and, if error reports, throw an exception, terminate the execution and output the content of the problem record

Return value:

The new table sequence whose records are contents of the file object f.

Example:

	A
1	=file("D:\\score.txt").import()
2	=file("D:\\score.txt").import@t()
3	=file("D:\\score.txt").import(;1:2)	With F_i and s omitted, get the data of the first of the multiple segments
4	=file("D:\\Department2.txt").import(;"\|")	With F_i, k and n omitted, the whole file is imported
5	=file("D:\\Department2.txt").import(;1:3,"\|")	Omit the fields to be imported
6	=file("D:\\ EMPLOYEE.txt").import@c(GENDER;1:2)	Retrieve the first segment of GENDER field of comma-seperated EMPLOYEE1.txt
7	=file("D:\\Department5.txt").import@t(DEPT, MANAGER:int; 1:3,"/")	The contents of Department5.txt are separated with slash and retrieved by the specified fields DEPT and MANAGER
8	=file("D:\\ score.txt").import@e(EID;1:3)	Return null because there’s no EID field in score.txt
9	=file("D:\\Department.txt").import@ts()
10	=file("D:\\EMPLOYEE.btx").import@b(;1:2)	Retrieve the first segment of the bin file (a segmented binary file) EMPLOYEE.btx, which is exported from f.export(A,x:F,…).
11	=file("D:\\orders.txt").import@mt(;",")	Increase the speed of retrieving data from the big file. The record order in the result is not the same as that in the file.
12	=file("D:\\StuName.txt").import@i()	StuName.txt has only one column, so return it as a sequence
13	=file("D:\\test.txt").import@t()
14	=file("D:\\test.txt").import@tq()
15	=file("D:\\Sale1.txt").import()	Get all records from Sale1.txt
16	=file("D:\\ Sale1.txt").import(#1,#3)	Get the first column and the third column from Sale1.txt
17	=file("D:/Dep3.txt").import@qo()	Here is the Dep3.txt file: Return the result:
18	=file("D:/Dep1.txt").import@k()	Retain the whitespaces on both sides of the data item
19	=file("D:/Department1.txt").import@t(id:int,name;,"\|")
20	=file("D:/Department1.txt").import@td(id:int,name;,"\|")	Delete the record as it contains unmatching data types
21	=file("D:/Department1.txt").import@tv(id:int,name;,"\|")	Check data type matching, and, if error reports, throw an exception, terminate the execution and output the content of the problem record
22	=file("Dep2.txt").import@tdn(id:int,name,surname;,"\|")	Here’s the file Dep2.txt: Ignore and discard row 6 and row 8 because the number of columns don’t match that of the first row
23	=file("D://EMP1.txt").import@s(;1:2)	Don’t split field values to import as a single-field table; ignore the parameters
24	=file("D://EMP2.txt").import(#1:date:"yyyy/MM/dd")	EMP2txt: Parse data in yyyy/MM/dd format as a date type field

Note:

Text file format: Separate records by carriage return, and fields by the user-defined separator. The default separator is the tab.

Related functions:

T.import()^{^[721]}^{^[722]}

Description:

Read in records from an entity table and return them as a sequence, record sequence or table sequence.

Syntax:

T.import(...)

Remark:

The function, which is equivalent to T.cursor(...).fetch(), retrieves records from entity table T and returns them as a sequence, record sequence or table sequence.

Parameters:

T	An entity table

Return value:

A sequence/record sequence/table sequence

Example:

	A
1	for 100
2	=to(10000).new(#:k1,rand():c1).sort@o(k1)	Generate a set of random data
3	*=to(10000).new(#:k1,rand(10000):c2,rand()1000:c3).sort@o(k1)**
4	=A2.cursor()
5	=A3.cursor()
6	=file("D:\\tb1.ctx")	Create composite table’s base table
7	=A6.create(#k1,c1;k1)
8	=A7.append(A4)
9	=A7.attach(table4,c2,c3)
10	=A9.append(A5)
11	=A9.cursor(;c2<1000;2:3)	Divide records in A9’s attached table where c2 is less than 1000 into 3 segments and return columns in the 2^nd segment as a cursor
12	=A11.fetch()	Fetch data from A11’s cursor
13	=A9.import(;c2<1000;2:3)	Same result as A12

index()[723][724]

Here’s how to use index() function.

T.index()[725][726]

Description:

Create an index table for the key of a table sequence.

Syntax:

T.index(n)

Note:

The function creates an index table, whose length is n, for the key of table sequence T. The index table will be cleared if n=0, or when the table sequence’s key is reset; the index table’s length will be automatically identified if n isn’t supplied. An index table can help speed up the key-based data query process. To create an index table, we assume that there is only one key for the records, otherwise error will be reported.

Options:

@s	Create a multilevel tree-structure index and ignore parameter n if the TSeq’s key is for data ordering

Parameters:

T	A table sequence with a key
n	Index length

Return value:

Table sequence

Example:

	A
1	=demo.query("select EID,NAME,SALARY from EMPLOYEE where EID<4")
2	=A1.keys(EID)	Set EID as A1’s key
3	=A1.index(10)	Create an index table for the table squence’s key; the length is 10

Related functions:

r.key()

T.index(n)[727][728]

Description:

Create an index for the key of a memory table.

Syntax:

T.index(n)

Note:

The function creates an index whose length is n for the key of memory table T. Parameter n can be omitted if the key contains serial byte values. The index facilitates data searching when we need to perform multiple searching according to the primary key. The function assumes there is only one primary key in records.

Parameters:

T	A memory table with only one primary key
n	The length of index

Return value:

A memory table

Example:

	A
1	=file("D:\\emp3.ctx")
2	=A1.create(#EID,NAME;EID)	Create a composite table’s base table
3	=demo.cursor("select EID,NAME from employee where EID< 10")
4	=A2.append(A3)
5	=A2.attach(table3,#GENDER)	Add an attached table to the base table
6	=demo.cursor("select EID,GENDER from employee where EID< 10")	Return a cursor
7	=A5.append(A6)	Append cursor records to the attached table
8	=A5.memory()	Generate a memory table from A5’s attached table
9	=A8.keys(EID)	Set EID field as the memory table’s key
10	=A8.index(10)	Create an index whose length is 10

T.index(I:h,w;C,…;F,…)[729][730]

Description:

Create an index file for an entity table.

Syntax:

T.index(I:h,w;C,…;F,…)

Note:

The function creates index I for records meeting filtering condition w in entity table T according to keys C,…, which should not the field(s) inheriting from the parent table. The parameter w can be omitted; create a hash index with the average length as h if parameter h is present. The key(s) C,… and index name I are indispensable for creating the index. The index name should be unique, and an index file with the unique name will be automatically generated when the index creation is successfully executed. The function deletes the corresponding index when there is only one parameter I; delete all indexes of T if all parameters are absent. A hash index can be only used for performing equivalence query and supports the contain syntax.

Parameter F is the field name in the entity table. When it is present, record the field into the index file. We can only get the indexed fields C and F field when using the index to retrieve records. The greatest aspect of such an index is that we can quickly find values of F field through values of C. If parameter F is absent, the index will record the location information of all the fields in the entity table.

Parameters:

T	An entity table
I	Index name
w	Filtering condition; retrieve the whose set if the parameter is absent
C	The field for which an index is created
h	Index length
F	Field name in an entity table; can be omitted

Options:

@2	Auto-load and maintain the second-level index when only parameter I is present
@3	Auto-load and maintain the third-level index when only parameter I is present
@0	Close the index to release resources when only parameter I is present
@w	Create a full-table index based on a certain column and support like(“X”) style search

Return value:

Boolean value

Example:

	A
1	=file("D:\\emp1.ctx")
2	=A1.create(#EID,NAME;EID)	Create a composite table where EID field is the key by which records are segmented
3	=demo.cursor("select EID,NAME from employee where EID< 10")
4	=A2.append(A3)	Append cursor records to the base table
5	=A2.attach(table1,DEPT,GENDER)	Add attached table table1 to the base table
6	=demo.cursor("select EID,DEPT,GENDER from employee where EID< 10")
7	=A5.append(A6)	Append cursor records to entity table table1
8	=A7.index(test_index,GENDER=="F";DEPT;)	Create an index test_index1 by DEPT field
9	=A5.index(test_index3,["F"].contain(GENDER);DEPT;)	Use the contain syntax to create index test_index3 by DEPT field
10	=A5.index(idx1:10;DEPT;)	Create index idx1 with the length of 10 by DEPT field
11	=A5.index(test_index3)	Delete index test_index3
12	=A5.index()	Delete all indexes
13	=A5.index(test_index,GENDER=="F";DEPT;GENDER)	Via the index, get records with only the indexed field DEPT and GENDER field
14	=A7.index@w(test_index,GENDER=="F";DEPT;)	Create a full-table index based on DEPT
15	=A14.icursor (;like(DEPT,"ale"),test_index).fetch()	Use like(“X”) style search

inf()[731][732]

Here’s how to use inf() function.

inf()[733][734]

Description:

Return positive infinity value.

Syntax:

inf()

Note:

The function returns the positive infinity value.

Return value:

Positive infinity value

Example:

inf()

Infinity

Related functions:

-inf()

-inf()[735][736]

Description:

Return negative infinity value.

Syntax:

-inf()

Note:

The function returns the negative infinity value.

Return value:

Negative infinity value

Example:

-inf()

-Infinity

Related functions:

inf()

insert()[737][738]

Here’s how to use insert() function.

A.insert()[739][740]

Description:

Insert members into a sequence.

Syntax:

A.insert(k,X)	Insert the members of sequence X before position k in A, and return A.
A.insert(k,x)	Insert member x before position k in A, and return A.

Note:

The function inserts member x or members of sequence X before position k in sequence A. When parameter k is omitted, we assume the sequence A is ordered and insert member X(or x); if member X(or x) have already existed in A, the function won’t perform the insertion. Automatically update the index, if any, and check distinctness.

Parameters:

k	The position before which one or more members are inserted, when k==0, the member(s) will be appended in the end.
A	A sequence
X	A sequence composed of the members to be inserted
x	A member

Options:

@n	Return the inserted record or a record sequence of the inserted records.

Return value:

The sequence into which you have inserted new members

Example:

	A
1	=["a","c","d","e","f"]
2	=A1.insert(0,"g")	[a,c,d,e,f,g], the member is appended in the end and A1 changes
3	=A1.insert(2,["g","j"])	[a,g,j,c,d,e,f,g], insert the new members before the second member.
4	=demo.query("select * from STUDENTS")
5	=A4.insert@n(2,ID+10:ID,"Lily":NAME,"M":GENDER,15:AGE)	Return the inserted record
6	=A1.insert(,"b")	[a,b,g,j,c,d,e,f,g]; assume A1 is ordered and insert a new member b
7	=A1.insert(,"a")	[a,b,g,j,c,d,e,f,g]; member a exists in A1, so the same member won’t be inserted

Related functions:

A.delete()

A.modify()

T.insert()

T.insert()[741][742]

Description:

Insert one or more records into a table sequence.

Syntax:

T.insert(k)	Insert an empty record before the position k in the T. If k is 0, then append it in the end and return the new T
T.insert(k,xi:Fi,…)	Insert a record into T before the position k where the value of Fi is xi and return the new T. When parameter k is omitted, we assume the table sequence T is already ordered by the key and insert records; if the key value has already existed, the function won’t perform the insertion.
T.insert(k:A,xi:Fi,…)	Insert multiple records into T before the position k where the value of Fi is xi and return the new T . The number of the records to be inserted is determined by the length of sequence A.

Note:

The function inserts one or more records into the table sequence T, and automatically updates the index, if any, and checks distinctness.

Parameters:

k	The position before which the member, or the record, is inserted. When k==0, append it in the end.
xi	The Fi field value before which the new record is to be inserted
Fi	The name of field where xi resides; without Fi, it will be the corresponding i^th field.
T	A table sequence
A	A sequence or an integer; if A is an integer, then it is equal to to(A)

Options:

@n	Return the inserted record or a record sequence of the inserted records
@r(k:A)	Insert sequence A into table squence T from the k^th record according to the order of the fields
@f(k:A)	Insert sequence A into table squence T from the k^th record; only the common fields are inserted.

Return value:

The table sequence T into which you have inserted new records

Example:

	A
1	=create(id,name,age)
2	=A1.insert(0,1,"Jack",29)
3	=A1.insert(1,2,"Lucy",30)
4	=A1.insert(0)
5	=A1.insert(0:3)
6	=A1.insert@n(1:1,10,"Lily",30)	Return the inserted record
7	=create(ID,Name,Age)
8	=A7.insert(0:A1,id:ID,name:Name,age:Age)
9	=A1.delete(A1.select(id<2))
10	=A7.insert@r(5:A9)		Insert A9 into A7 from the fifth record
11	=create(ID,Name,AGE)
12	=A11.insert@f(3:A7)		Insert only the ID and Name fields of A7 to A11 from the third record
13	=A1.keys(id)		Set id as A1’s primary key, then A1’s data is as follows:
14	=A1.insert(,5,"Mary",28)		Parameter k is omitted; assume A1 is already ordered by id and insert the records
15	=A1.insert(,2,"CC",32)		Same result as A14; since the record where the key value is 2 already exists, the function cancels the insertion
16	=file("D:\\test.txt").import@t()		test.txt defines only the column headers
17	=A16.insert(0,1,"2008-8-4")		Insert a record

Related functions:

Perform interative loop on record sequences in a channel and return the result of the last calculation of a given expression.

T.delete()

A.insert()

int()[743][744]

Description:

This is a data type conversion function. It is used to obtain the integer part of a given numeric value expression or a numeric string, and convert its data type to 32-bit integer.

Syntax:

int(valueExp)

Note:

The returned result of valueExp must be a numeric string or a number.

Parameters:

valueExp

An expression, the result of which must be a numeric string or a number.

Return value:

A 32-bit integer

Example:

int("33")	33
int("33.999d")	33
int(1.5*1.5)	2
int(25.67)	25

Related functions:

float()

decimal()

long()

number()

string()

interval()[745][746]

Description:

Compute the interval between two datetime values

Syntax:

interval (datetimeExp1,datetimeExp2)

datetimeExp1- datetimeExp2

interval (datetimeExp2,datetimeExp1)

Note:

The function computes the interval between two datetime values datetimeExp1 and datetimeExp2

Parameters:

datetimeExp1	The date expression whose value is a datetime or a string of standard datetime format
datetimeExp2	The date expression whose value is a datetime or a string of standard datetime format

Options:

@y	Compute the years between two datetime values
@q	Compute the quarters between two datetime values
@m	Compute the months between two datetime values
@s	Compute the seconds between two datetime values
@ms	Compute the milliseconds between two datetime values
@r	Compute the interval between two datetime values and return a real number
	By default it computes the days between two datetime values
@w	Compute the weeks between two datetime values
@7	Compute the number of Sundays between two datetime values according to a left-open interval
@1	Compute the number of Mondays between two datetime values according to a left-open interval

Return value:

Integer

Example:

	interval(datetime("19800227","yyyyMMdd"),datetime("1983-02-27 00:00:45"))	1096
	interval@y(datetime("19800227","yyyyMMdd"),datetime("1983-02-27 00:00:45"))	3
	interval@q(datetime("19800227","yyyyMMdd"),datetime("1983-02-27 00:00:45"))	12
	interval@m(datetime("19800227","yyyyMMdd"),datetime("1983-02-27 00:00:45"))	36
	interval@s(datetime("19800227","yyyyMMdd"),datetime("1980-02-27 00:00:45"))	45
	interval@s ("1972-11-08 10:20:30","1972-11-08 10:30:50")	620
	interval@ms(datetime("19800227","yyyyMMdd"),datetime("1980-02-27 00:00:45"))	45,000
	interval@ms("1972-11-08 10:20:30","1972-11-08 10:30:50")	620,000
	interval@r(datetime("19800227","yyyyMMdd"),datetime("1980-02-27 00:00:45"))	5.208333333333333E-4
	interval@r("1972-11-08 10:20:30","1973-11-08 10:30:50")	365.00717592592594
	datetime("19850227","yyyyMMdd")-datetime("1983-02-27 00:00:45")	731
interval@w("1972-10-08 10:20:30","1972-11-08 10:30:50")
interval@7("1972-10-08 10:20:30","1972-11-08 10:30:50")
interval@1("1972-10-08 10:20:30","1972-11-08 10:30:50")

inv()[747][748]

Here’s how to use inv() function.

A.inv(p)[749][750]

Description:

Adjust the order of members of a sequence.

Syntax:

A.inv(p)

Note:

The function adjusts the order of members of A according to the integer sequence p, whose members are ranks of members of sequence A, and return the new A.

Parameters:

p	An integer sequence, whose members are ranks of members of A. So the number of its members is the same as that of members of A, and it is a unique n-integer sequence (n=A.len()).
A	A sequence or a record sequence.

Return value:

The adjusted sequence

Example:

	A
1	[b,c,a,d]
2	=A1.inv([2,3,1,4])	[a,b,c,d]

Note:

p must be a unique n-integer sequence, i.e. n must be equal to A.len()

If p has duplicate members or the number of its members is not equal to that of members of A, return null.

If the maximum member value of p exceeds the maximum sequence number of A, return null

The members of tied ranks will be ignored

Related functions:

p.inv(k)

p.inv(k)[751][752]

Description:

Compute the sequence numbers of an integer’s members in another integer sequence.

Syntax:

p.inv(k)

Note:

The function returns the sequence numbers of the mumbers from 1 to k in integer sequence p. Return 0 for the numbers that do not exist in p.

Parameters:

p	An integer sequence
k	An integer, which is p.len() by default

Return value:

An integer sequence composed of the sequence numbers of the integers from 1 to k in integer sequence p

Example:

	A
1	=[1,3,5,7]
2	=A1.inv(4)	Among the four numbers 1, 2, 3 and 4, the sequence numbers of 1 and 3 in sequence A1 are 1 and 2. 2 and 4 do not exist in sequence A1, so their sequence numbers are 0. [1,0,2,0] is returned finally.

Related functions:

A.inv(p)

invoke()[753][754]

Description:

Invoke the static function of class in the package.

Syntax:

invoke(p.c.f,a_i,…)

Note:

The function, in which a_i is the parameter, calls the static function f of class c in the package p, which can be omitted.

Parameters:

p	Package path
c	Class name
f	Static method name
a_i	Parameter

The following lists data types of the parameters passed for the invoke() function and their corresponding parameter data types in Java classes:

Bool	java.lang.Boolean
Int	java.lang.Integer
Long	java.lang.Long
Float	java.lang.Double
Decimal	java.math.BigDecimal
Date	java.sql.Date
Time	java.sql.Time
Datetime	java.sql.Timerstamp
String	java.lang.String
Blob	byte []

Example:

(I) package api;

public class Calc01 {

public static Double distance1(Number loc) {

double len = Math.abs(loc.doubleValue());

len = Math.round(len*1000)/1000d;

return Double.valueOf(len);

}

	A
1	-12.34567
2	=invoke(api.Calc01.distance1,A1)
3	=invoke(api.Calc01.distance1, -512)

The static method distance1 calculates the distance between a given point and the origin, with the result rounded to 3 decimal places. A method invoked in an esProc cellset file should be both static and public.

(II) Create a customized class LineReaders for implementing the ILineInput interface so that users can retrieve a various types of data files using the file cursor. The file path can be defined as a parameter to be passed to the customized class. Then the file contents can be retrieved through stream in a row-wise fashion or by skipping certain individual rows; and the cursor can thus be closed in a certain way.

Below is a sample program:

package api;

import java.io.BufferedReader;

import java.io.EOFException;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStreamReader;

import java.text.DateFormat;

import java.text.ParseException;

import java.text.SimpleDateFormat;

import com.raqsoft.dm.ILineInput;

import com.raqsoft.dm.UserUtils;

import com.raqsoft.dm.cursor.ICursor;

public class LineReaders implements ILineInput {

private String pathName;

private boolean hasTitle;

private BufferedReader bfr;

final String COL_SEP = "\t";

final String encoding = "UTF-8";

String lineTxt = null;

final DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

String[] rowData;

Object[] datas = new Object[3];

public LineReaders(String pathName,boolean hasTitle) {

this.pathName = pathName;

this.hasTitle=hasTitle;

}

public static LineReaders newInstance(String pathName,boolean hasTitle) {

return new LineReaders(pathName,hasTitle);

}

private BufferedReader getBufferedReader() throws IOException {

if (bfr == null) {

File file = new File(pathName);

if (file.isFile() && file.exists()) { // Check if the file exists

InputStreamReader read = new InputStreamReader(new FileInputStream(file), encoding);// Take the type of character encoding into consideration

bfr = new BufferedReader(read);

}

return bfr;

}

//Read an individual row

public Object[] readLine() throws IOException {

BufferedReader bfr = getBufferedReader();

try {

if (!hasTitle) {

datas[0] = "ID";

datas[1] = "BirthDate";

datas[2] = "Name";

}

while ((lineTxt = bfr.readLine()) != null) {

rowData = lineTxt.split(COL_SEP);

if (rowData != null && rowData.length == 3) {

if (hasTitle) {

datas[0] = rowData[0];

datas[1] = rowData[1];

datas[2] = rowData[2];

hasTitle = false;

return datas;

}

datas[0] = Integer.parseInt(rowData[0]);

datas[1] = df.parse(rowData[1]);

datas[2] = rowData[2];

return datas;

}

return null;

} catch (EOFException e) {

return null;

} catch (ParseException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return datas;

}

// Convert the ILineInput instance to a cursor

public static ICursor UserUtilsReader(String pathName,boolean hasTitle){

return UserUtils.newCursor(newInstance(pathName,hasTitle), "t");

}

//Skip an individual row

public boolean skipLine() throws IOException{

BufferedReader bfr = getBufferedReader();

try {

String s = bfr.readLine();

if(s!=null){

return true;

}

} catch (EOFException e) {

return false;

}

return false;

}

//Close the cursor

public void close() throws IOException {

if (bfr != null) {

bfr.close();

bfr = null;

}

(II) Place a LineReaders.class file in the api folder in the [esProc installation root directory]/classes path.

(III) The contents of the file (it uses the character encoding of UTF-8) retrieved by a cursor are as follows:

(IV) Invoke the customized function with invoke() function in the esProc cellset file:

	A
1	=invoke(api.LineReaders.UserUtilsReader,"D://abc.txt",true)	Call the customized function
2	=A1.skip(3)	3
3	=A1.fetch()

isalpha()[755][756]

Description:

Check if a string is composed of letters.

Syntax:

isalpha(s)

Note:

The function checks if string s is composed of letters. If s is an integer, look it up in the ASCII table to see if the corresponding characters are letters.

Parameters:

s	String/ numeric expression

Return value:

Boolean value

Example:

isalpha("abc")	true
isalpha(97)	true
isalpha("@#$")	false
isalpha("1@23")	false
isalpha("a@23")	false

Related functions:

isdigit()

isdigit()[757][758]

Description:

Check if a string is composed of numbers.

Syntax:

isdigit (string)

Note:

The function checks if the string string is composed of numbers. If string is an integer, look it up in the ASCII table to see if the corresponding characters are a number.

Parameters:

String

String/ numeric expression

Return value:

Boolean value

Example:

isdigit("123")	true
isdigit(123)	false
isdigit("abc")	false
isdigit("123ss")	false

Related functions:

isalpha()

isect()[759][760]

Here’s how to use isect() function.

A.isect()[761][762]

Description:

Compute the intersection of all the sequences that are members of a larger sequence.

Syntax:

A.isect()

Note:

Members of sequence A are also sequences. The function creates a new sequence composed of all common members of the sub-sequences.

Parameters:

A	A sequence whose members are also sequences.

Return value:

A sequence

Example:

	A
1	=[[1,2,3,4,5],[3,7,8]].isect()	[3]
2	=[[1,2,3],[3,2]].isect()	[2,3]
3	=[[1,2,2,3],2].isect()	[2]
4	=demo.query("select top 2 * from EMPLOYEE")
5	=demo.query("select top 1 * from EMPLOYEE")
6	=[A4,A5].isect()	[] Since A4 and A5 come from different table sequences and have different store addresses, so same records are regarded as different members

Related functions:

A.isect(x)[763][764]

Description:

Compute x with each member of the sequence whose members are sequences, and then perform intersection operation between members of the new sequence.

Syntax:

A.isect(x)

Note:

Members of sequence A are also sequences. The function loops through members of sequence A to compute expression x and creates a sequence composed of all common members of the new sub-sequences.

Parameters:

A	A sequence whose members are also sequences
x	An expression that returns a sequence

Return value:

A sequence

Example:

	A
1	=demo.query("select * from EMPLOYEE where GENDER = 'M' order by NAME")
2	=demo.query("select * from EMPLOYEE where GENDER = 'F' order by NAME")
3	=[A1,A2].isect(~.(NAME))	Intersection operation between A1 and A2

Related functions:

A.isect()

iselect()[765][766]

Here’s how to use iselect() function.

f.iselect()[767][768]

Description:

Create a cursor based on an ordered file and return it.

Syntax:

f.iselect(A,x;F_i,…;s)	Retrieve records from file f that is ordered by field/expression x, according to the criterion that the values of x should be members of sequence A, and return them as a cursor
f.iselect(a:b,x;F_i,…;s)	Rtrieve records from file f that is ordered by field/expression x, according to the criterion that the values of x should fall in the interval [a:b], and return them as a cursor

Note:

The function retrieves records from file f that is ordered by x field, according to the criterion that the values of x should be members of sequence A, or fall in the interval [a:b], and returns the records as a cursor. By default the values of x are all considered distinct in f.

Parameters:

f	A file object
A	A single value or a sequence
a	Field value
b	Field value
x	Field name/expression; the sign # is used to represent a field with a sequence number
F_i	Fields to be retrieved, and all fields will be retrieved by default
s	User-defined separator. The default is tab. When the parameter is omitted, the comma preceding it can be omitted, too

Options:

@t	Use the first row of f as the field names. If omitted, then use_1,_2,… as the default field names
@b	Retrieve data from an exported binary file, with the support for parameters A, x and F_i, and with no support available forparameter s. Ignore options @t and @c. Segments containing no records may appear if it is a file containing a small number of records; an error report will appear if the file isn’t segmented when being retrieved.
@c	Use comma as the separator when the parameter s is absent. But the user-defined separator s should take priority when there is one.
@r	Find all records with the same value of x field; by default x is distinct in the file f.
@q	First remove quotation marks surrounding strings, including the headers, and then handle the escaping
@o	Use quotation marks as the escape character
@k	Retain the white space on both sides of the data item; without it a trim operation will be automatically performed
@e	Return a null column if parameter F_i doesn’t exist; the default way of handling is to report error
@d	Perform type matching and delete a record if there is mismatching data type or format in it
@v	Throw an exception, terminate execution, and output the content of the current record when type matching error appears
@n	Discard a row whose number of columns doesn’t match the number in the first row

Return value:

A cursor

Example:

	A
1	=to(1:10)
2	=file("E:/files/employee.txt").iselect(A1,#1;;"\|")	Below is the file employee.txt: The first column is ordered and is separated from the next column by "\|". No fields are specified to be retrieved, so all will be retrieved – if the value of the first one is in sequence A1 – and returned as a cursor.
3	=A2.fetch()
4	=file("E:/files/employee1.txt").iselect@t(A1,EID;EID,SALARY)	Below is the file employee1.txt: Retrieve corresponding EID and SALARY fields value – if EID value is in sequence A1 – and return them as a cursor
5	=A4.fetch()
6	=file("E:/files/employee2.txt").iselect@tc(A1,EID)	Below is the file employee2.txt: Comma is used as the seperator
7	=A6.fetch()
8	=file("E:/files/employee3.txt").iselect@b(A1,EID)	Retrieve the bin file employee3.txt exported through f.export@z(A,x:F,...;s) and get records where EID≤1 and ≥10
9	=A8.fetch()
10	=file("E:/files/employee1.txt").iselect@t(1:10,EID;EID,SALARY)	Retrieve EID field and SALARY field according to the condition that EID≤1 and ≥10
11	=A10.fetch()	Same result as A5
12	=file("D:/Sale2.txt").iselect@tr(7,ID;ID,ENAME)	Retrieve all records where ID is 7 from Sales2.txt:
13	=A12.fetch()
14	=file("D:/Department1.txt").iselect@t(1:5,id;id,name;"\|").fetch()
15	=file("D:/Department1.txt").iselect@tk(2,id;id,name;"\|").fetch()	Use @k option to retain whitespaces on both sides of the data item
16	=file("D:/Department1.txt").iselect@tq(1,id;id,name;"\|").fetch()	Remove quotation marks surrounding strings
17	=file("D:/Department1.txt").iselect@tqo(5,id;id,name;"\|").fetch()
18	=file("D:/emp1.txt").iselect@et(2:5,EID;EID,SALARY,SEX).fetch()	Below is the file emp1.txt: With @e option, the function returns an empty corresponding column since column SEX doesn’t exist in the file
19	=file("D:/emp1.txt").iselect@tn(7:10,EID;EID,NAME,SALARY).fetch()	Discard the row where EID is 10 since its number of columns isn’t the same as that in the first row
20	=file("D:/emp2.txt ").iselect@t(A1,EID-5;;",").fetch()	Get 10 records whose EIDs are from 5 to 15 and which satisfy the specified expression
21	=file("D:/emp2.txt ").iselect@t(1：10,EID-5;;",").fetch()	Use an interval to get the same result

islower()[769][770]

Description:

Check if a string is composed of lower case letters.

Syntax:

islower(string)

Note:

The function checks if the string string is composed of lower case letters. If string is an integer, look it up in the ASCII table to see if the corresponding characters are in lower case.

Parameters:

String

String expression/numeric expression

Return value:

Boolean value

Example:

islower("dgfdsgf")	true
islower(97)	true
islower("dsfaAFD")	false
islower("97ffdsf")	false

Related functions:

isupper()

isolate()[771][772]

Here’s how to use isolate() function.

db.isolate()[773][774]

Description:

Define transaction isolation level for the connection according to the option and return the original level.

Syntax:

db.isolate()

Note:

The function sets transaction isolation level for the connection according to the option and returns the original level, i.e. its corresponding character of the option. Establish the connection via JDBC by default if no option is used.

Option:

@ncurs

Correspond to NONE,READ_COMMITTED,READ_UNCOMMITTED,REPEATABLE_READ,SERIALIZABLE respectively

Parameters:

db	Database connection

Return value:

The orignal level of the database connection

Example:

	A
1	=connect("demo")
2	=A1.isolate@r()	Set transaction isolation level as REPEATABLE_READ and return the original level " c"

Related functions:

connect()

isupper()[775][776]

Description:

Check if a string is composed of upper case letters.

Syntax:

isupper(string)

Note:

The function checks if the string string is composed of upper case letters. If string is an integer, look it up in the ASCII table to see if the correponding characters are in upper case.

Parameters:

String

String expression/numeric expression

Return value:

Boolean value

Example:

isupper("ADSFDGKJ")	true
isupper(85)	true
isupper("SDsdsSDAS")	false
isupper("8ASDS7")	false

Related functions:

islower()

iterate()[777][778]

Here’s how to use iterate() function.

A.iterate()[779][780]

Description:

Perform interative loop on a record sequence and return the result of the last calculation of a given expression.

Syntax:

A.iterate(x,a,c)

Note:

The function loops through members of record sequence A to calculate expression x and returns the result of the last calculation of x. ~~ represents the previous value of x. Parameter a is the default initial value for each calculation, whose absence indicates a null initial value. Exit the loop once the result of expression c is true.

Parameters:

A	A sequence/record sequence
x	An expression
a	The initial value
c	A boolean expression

Options:

@a	Return the results of calculating the expression over every member

Return value:

Result of expression x

Example:

	A
1	[2,222,22,122,2222]
2	*=A1.iterate(~2)**	4444
3	*=A1.iterate@a(~2)**	[4,444,44,244,4444]
4	*=A1.iterate(~~2,3)**	96
5	*=A1.iterate(~~2,5,~>500)**	80
6	*=demo.query("select from SALES")**
7	*=A6.derive(A6.(AMOUNT).iterate(~~2,5,~>20000):Cumulation)**

Related functions:

iterate()

ch.iterate()^{^[781]}^{^[782]}

Description:

Syntax:

ch.iterate(x,a,c)

Note:

The function loops through record sequences in channel ch to calculate expression x and returns the result of the last calculation of x. ~~ represents the previous value of x. Parameter a is the default initial value for each calculation, whose absence indicates a null initial value. Exit the loop once the result of expression c is true.

Parameters:

ch	A channel
x	An expression
a	Initial value
c	An expression returns true/false

Return value:

Result of expression x

Example:

	A
1	=[2,222,22,122,2222]
2	=channel()
3	=channel()
4	*=A2.iterate(~2)**
5	*=A3.iterate(~~2,3)**
6	=A1.push(A2,A3)
7	=A2.result()	4444
8	=A3.result()	96
9	=[100,200,800,2000]
10	=channel()
11	*=A10.iterate(~~3,10,~>250)**
12	=A9.push(A10)
13	=A10.result()	90

cs.iterate()^{^[783]}^{^[784]}

Description:

Perform interative loop on record sequences in a cursor and return the result of the last calculation of a given expression.

Syntax:

cs.iterate(x,a,c)

Note:

The function loops through record sequences in cursor cs to calculate expression x and returns the result of the last calculation of x. ~~ represents the previous value of x. Parameter a is the default initial value for each calculation, whose absence indicates a null initial value. Exit the loop once the result of expression c is true.

Parameters:

cs	A cursor
x	An expression
a	Initial value
c	An expression returns true/false

Return value:

Result of expression x

Example:

	A
1	=[2,222,22,122,2222].cursor()
2	*=A1.iterate(~2)**	4444
3	*=[2,222,22,122,2222].cursor().iterate(~~2,3)**	96
4	*=[2,222,22,122,2222].cursor().iterate(~~2,5,~>500)**	80
5	*=demo.cursor("select from SALES")**
6	*=A5.(AMOUNT).iterate(~~2,5,~>20000)**	40

iterate()[785][786]

Description:

An iterative loop for calculating an expression.

Syntax:

iterate(x,a;G_i,…)

Note:

The function performs an interative loop to compute expression x – which contains a ~~, and returns the result. Each time when the value of field G_ichanges, the value of ~~ becomes a. The parameter G_ican be omitted. When parameter a isn’t supplied, its value is null.

Parameters:

x	An expression containing ~~
a	Initial value
G_i	Field name

Return value:

Value of the given expression

Example:

	A
1	*=demo.query("select top 7 from SCORES ")**
2	*=A1.groups(CLASS:Class,STUDENTID:StudentID;iterate(~~2): Score1)**
3	*=A1.groups(CLASS:Class,STUDENTID:StudentID;iterate(~~2,10): Score1)**
4	*=A1.derive(iterate(~~2,10;STUDENTID):F1)**

Related functions:

A.iterate()

join()[787][788]

Here’s how to use join() function.

join()[789][790]

Description:

Join multiple sequences together.

Syntax:

join(A_i:F_i,x_j,..;…)

Note:

The function joins multiple sequences of A_i according to the condition that the value of relational field/expression x_jisequal to x₁, and generates a table sequence whose fields are F_i,…. which reference the records of the original record sequences A_i. If x_j is omitted, then use the key of A_i. An omitted x_j won’t be matched. No matter how many record sequences are mutually related, the equivalence determination is conducted according to the x1 in A1. Therefore this is a one-to-many relationship.

Parameters:

Fi	Field name of the resulting table sequence
Ai	Sequences or record sequences to be joined
xj	Relational field/ expression

Options:

@f	Full join;if no matching records are found, then use nulls to correspond
@1	Left join; it is the number "1" instead of the letter "l"
@m	If all A_iare ordered against x_j_, then use merge operation to compute
@p	Perform a join according to positions while ignoring parameter xj
@x	If field values of the sequences to be joined are records, the joining values will be unfolded

Return value:

A new table sequence whose fields are all referencing ones

Example:

	A
1	=demo.query("select top 3 EID,NAME from EMPLOYEE").keys(EID)
2	=demo.query("select top 3 EID,NAME from FAMILY").keys(EID)
3	=join(A1:Employee,EID;A2:Familymembers,EID)
4	=join@f(A1:Employee,EID;A2:Familymembers,EID)	Full join. If no matches, then use the nulls
5	=join@1(A1:Employee,EID;A2:Familymembers,EID)
6	=join@m(A1:Employee,EID;A2:Familymembers,EID)
7	=join@p(A1:Employee;A2:Familymembers)
8	=join(A1:Employee;A2:Familymembers)
9	=join(A1:Employee1;A2:Familymembers1)
10	=join(A7:Employee2;A8:Familymembers2)
11	=join@x(A7:Employee2;A8:Familymembers2)	Field values of A7 and A8 are records, the joining values will be unfolded

Related functions:

xjoin()

A.join()[791][792]

Description:

A foreign-key-style join between table sequences/record sequences, or a table sequence and a record sequence.

Syntax:

A.join(C:.,T:K,x:F,…; …;…)

Note:

The function matches C field of table sequence/record sequence A with the key of table sequence/record sequence T to find the desired records. Add an F field represented by x, which is T’s field expression, to A to generate a new table sequence. K can be omitted or represented by #. When omitted, K is T’s key; when written as #, K is represented by a sequence number.

Options:

@i	Delete a record with a non-matching foreign key value; by default a non-matching record will be represented by null. If parameters x:F are omitted, perform the filtering purely over parameter A
@o(F;)	Use the record as the value of F field to generate a new record; here expression x is equivalent to ~
@d	If parameter x:F is absent, delete the records matching the foreign key and perform the filtering operation only over table sequence/record sequence A
@k	When parameter x is ~, record the relationship between parameter F and parameter C to identify the potentially associative foreign key

Parameters:

A	Table sequence/record sequence
C	A’s foreign key; separate multiple fields in a composite key with the colon
T	Table sequence/record sequence/memory table
K	T’s key
x	T’s field expression, which can be represented by ~ and #; the pound sign # represents the sequence number of a record in T; record the sequence number as 0 if a record doesn’t exist in T
F	Field name in expression x

Return value:

A table sequence/record sequence

Example:

	A
1	*=demo.query("select from EMPLOYEE order by EID" )**
2	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)**
3	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").cursor().memory().keys(EMPLOYEEID)**	Return a memory table
4	=A1.join(EID,A2,BONUS+1:SALARY1)	Use null to represent a record with non-matching foreign key value
5	=A1.join(EID,A3,BONUS+1:SALARY1)	A3 is a memory table; the resut is the same as above, where null is used to represent a record with non-matching foreign key value
6	=A1.join@i(EID,A2,BONUS+1:SALARY1)	Delete a record with non-matching foreign key value
7	=A1.join@i(EID,A2:#1,BONUS+1:SALARY1)	Same result as A4’s; #1 means the first field
8	=A1.join@o(F1;EID,A2,BONUS+1:SALARY1)	Records are the values of F1 field
9	=A1.join@i(EID,A2)	As parameters x:F are omitted, perform the filtering purely over parameter A1
10	=A1.join@d(EID,A2)	Since parameter x:F is absent, delete the records matching the foreign key and perform the filtering operation only over A1

ch.join()[793][794]

Description:

A foreign-key-style join between a channel and a record sequence.

Syntax:

ch.join(C:.,T:K,x:F,…; …;…)

Note:

The function uses the key of table sequence/record sequence T to match C,… field in channel ch, and add an F field to ch by joining T’s field expression x to for a new channel. K can be omitted or represented by #; when it is omitted, use T’s key; when represented by #, the key is pointed by a sequence number. This is an attached computation.

Options:

@i	Delete the whole record if the foreign key can’t be matched; by default make it null.
@o(F;…)	Generate a new record by introducing the original record as a new field; field expression x can be represented by ~.

Parameters:

ch	Channel
C	Foreign key of a given channel; use comma to separate a composite key
T	Table sequence/record sequence
K	Key of the given table sequence/record sequence
x	A field expression of the given table sequence/record sequence
F	Name of the field expression

Return value:

Channel

Example:

	A
1	=demo.cursor("select EID,NAME,SALARY from EMPLOYEE order by EID" )
2	=demo.query("select * from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)
3	=channel()	Create a channel
4	=channel()
5	=channel()
6	=channel()
7	=A1.push(A3,A4,A5,A6)	Be ready to push data in A1’s cursor into channel A3,A4,A5 and A6, but the action needs to wait
8	=A3.join(EID,A2, BONUS+1:SALARY1)	A normal join, where a record can’t be matched with the foreign key is recorded as null
9	=A8.fetch()	Fetch and store the existing data in the channel
10	=A4.join@i(EID,A2: #1, #3+1:SALARY1)	#1 represents the first field, and #3 represents the third field
11	=A10.fetch()
12	=A5.join@i(EID,A2, BONUS+1:SALARY1)	Delete the whole record since it doesn’t match the foreign key
13	=A12.fetch()
14	=A6.join@o(F1;EID,A2,~.BONUS+1:SALARY1)	Make the original record as the F1 field
15	=A14.fetch()
16	=A1.fetch()
17	=A3.result()
18	=A4.result()
19	=A5.result()	Get the same result as A18
20	=A6.result()

cs.join()[795][796]

Description:

A foreign-key-style join between a cursor and a table sequence/record sequence.

Syntax:

cs.join(C:.,T:K,x:F,…; …;…)

Note:

The function matches foreign key field C of cursor cs with the key of parameter T to find the corresponding records in T. Add an F field represented by x, which is T’s field expression, to cs and return the original cursor. K can be omitted or represented by #. When omitted, K is T’s key; when written as #, K is represented by a sequence number. It supports the multicursor.

Parameters:

cs	A cursor/A multicursor
C	Cursor cs’s foreign key; separate multiple fields in a composite key with the colon
T	A table sequence/A record sequence
K	T’s key
x	T’s field expression
F	Field name in expression x.

Options:

@i	Delete a record with a non-matching foreign key value; by default a non-matching record will be represented by null
@o(F;…)	Use the record as the value of F field to generate a new record; here expression x can be represented by ~, which is T’s record
@d	If parameters x:F are absent, only perform a filtering over the cursor by deleting its records where the foreign key is matched

Return value:

The orignal cursor

Example:

	A
1	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Return retrieved data as a cursor:
2	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)**	Return a table sequence:
3	=A1.join(EID,A2,BONUS+1:SALARY1)	Normal join; a non-matching record will be displayed as null
4	=A3.fetch()
5	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Same as A1
6	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)**	Same as A2
7	=A5.join@i(EID,A6, BONUS+1:SALARY1)	Delete non-matching records
8	=A7.fetch()
9	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Same as A1
10	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)**	Same as A2
11	=A9.join@i(EID,A10: #1, #3+1:SALARY1)	#1 represents the 1^st field; #3 represents the 3^rd field
12	=A11.fetch()	Same as A8
13	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Same as A1
14	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)**	Same as A2
15	=A13.join@o(F1;EID,A14,BONUS+1:SALARY1)	Use records as values of F1field
16	=A15.fetch()
17	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Same as A2
18	*=demo.query("select from PERFORMANCE order by EMPLOYEEID").keys(EMPLOYEEID)**	Same as A2
19	=A17.join@o(F1;EID,A18,~:SALARY1)	Replace parameter x with the sign ~
20	=A19.fetch()
21	=file("D:\\test7.ctx")
22	=A21.create(#EMPLOYEEID,EVALUATION,BONUS;EMPLOYEEID	Create a composite table
23	=A22.attach(table3,#EMPLOYEEID,EVALUATION,BONUS)	Add an attached table
24	*=demo.cursor("select from PERFORMANCE")**	Return a table sequence
25	=A23.append(A24)	Append records to A23’s attached table
26	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )

Related functions:

join()

cs.join()^{^[797]}^{^[798]}

Description:

A foreign-key-style join between a cluster cursor and a record sequence.

Syntax:

cs.join(C:.,T:K,x:F,…; …;…)

Note:

The function matches foreign key field C,… of cluster cursor cs with the key of parameter T to find corresponding records in table T. Add an F field represented by x, which is T’s field expression, to cs and return the original cluster cursor. K can be omitted or represented by #. When omitted, K is T’s key; when written as #, K is represented by a sequence number. It supports the multicursor.

Options:

@c	With a distributed cluster table, the operation won’t involve a cross-node reference but it assumes that the referenced records are local

Parameters:

cs	A cursor/multicursor/cluster cursor
C	cs’s foreign key; separate multiple fields in a composite key with the colon
T	A cluster memory table
K	T’s key
x	T’s field expression
F	Name of T’s field expression

Return value:

The original cursor

Example:

	A
1	[192.168.18.143:8281]
2	=file@0("emp_1.ctx", A1)
3	=A2.create()
4	=A3.cursor()	A cluster cursor
5	[192.168.0.110:8281]
6	=file@0("PERFORMANCE.ctx",A5)
7	=A6.create()
8	=A7.cursor()
9	=A8.memory()	A cluster memory table
10	*=A4.join(EID,A9:EMPLOYEEID, BONUS12:total)**	Match EID field of A4’s cluser cursor with the key field EMPLOYEEID of A9’s cluster memory table, make the value of calculating expression BONUS*12 over the memory table total field and join it up with the cluster cursor, and return the cluster cursor
11	=A10.fetch()	Fetch data from A10’s cursor

joinx()[799][800]

Here’s how to use joinx() function.

joinx()^{^[801]}^{^[802]}

Description:

Join table sequences retrieved from a series of cursors.

Syntax:

joinx(cs_i:F_i,x_j,..;…)

Note:

The function performs join@m over a resulting set generated from a series of ordered cursors csi and returns a new cursor. If parameter x_jis omitted, join the cursors according to their primary keys; if parameter x_jis present but there isn’t any primay key, perform the join based on values of x_j. The function can be also used to join multiple multicursors where each one must have the same number of parallel cursors or subcursor. Parameter csi can be a table sequence.

Supposing multiple cursors csi are already ordered by relational field/expression x_j, the function performs a join between them on the condition that x_j’s value is equivalent to the value of x₁field and returns a cursor consisting of F_i,…. fields. F_i,…. are referencing fields that reference the records of the cursors cs_i. Note: xj… only supports the ascending order.

Regardless of the number of cursors being joined, the equivalence determination is conducted according to cursor cs1’s x1 field. Therefore, it is a one-to-many relationship.

Options:

@f	Full join. If no matching records are found, then use nulls to correspond.
@1	Left join. Note that it is the number “1”, instead of letter “l”.
@p	Perform a join according to positions, while ignoring the parameter x_j
@u	Order by the key isn’t a must when cs1 is cursor while others are in-memory table sequences

Parameters:

cs_i	Cursors/table sequences being joined.
F_i	Field name of the result table sequence.
x_j	Relational field/expression.

Return value:

A cursor

Example:

	A
1	=demo.cursor("select * from EMPLOYEE order by EID" )
2	=demo.cursor("select * from PERFORMANCE order by EMPLOYEEID")
3	=join@x(A1:EmployeeID1,EID;A2:EmployeeID2,EMPLOYEEID)	Normal join. Discard the non-matching items, and each field value points to a record in the original cursor.
4	=A3.fetch()
5	=demo.cursor("select * from EMPLOYEE order by EID" )
6	=demo.cursor("select * from PERFORMANCE order by EMPLOYEEID")
7	=joinx@f(A5:EmployeeID1,EID;A6: EmployeeID2,EMPLOYEEID)	Full join. If no matching records, then use nulls to correspond.
8	=A7.fetch()
9	*=demo.cursor("select from EMPLOYEE order by EID" )**
10	*=demo.cursor("select from PERFORMANCE order by EMPLOYEEID")**
11	=joinx@1(A9:EmployeeID2,EID-5;A10:EmployeeID1,EMPLOYEEID)	Left join. The first cursor is regarded as the basis. If there are no matching records, then use null to correspond.
12	=A11.fetch()
13	=demo.cursor("select * from EMPLOYEE order by EID" )
14	=demo.cursor("select * from PERFORMANCE where EMPLOYEEID>3 order by EMPLOYEEID ")
15	=joinx@p(A13:EmployeeID2;A14:EmployeeID1).fetch()	Perform the join according to positions
16	=demo.query("select top 3 EID,NAME from EMPLOYEE")
17	=A16.modify(2,2,null)
18	=A16.cursor()
19	=demo.cursor("select top 20 * from EMPLOYEE")
20	=joinx(A18:Employee1,EID,NAME;A19: Employee2,EID,NAME)	Perform a join by EID and NAME fields
21	=A20.fetch()
22	=demo.query("select top 3 EID,NAME from EMPLOYEE").keys(EID)
23	=A22.cursor()
24	=demo.query("select top 20 * from EMPLOYEE").keys(EID)
25	=A24.cursor()
26	=joinx(A23:Employee1;A25: Employee2)	Perform the join according to primary keys
27	=A26.fetch()
28	=demo.cursor("select * from EMPLOYEE" )
29	=demo.query("select * from PERFORMANCE")
30	=joinx@u(A28:EmployeeID1,EID;A29:EmployeeID2,EMPLOYEEID)	With @u option, order by the ky isn’ required as only A28 is the cursor and others are in-memory table sequences
31	=A30.fetch()

Related functions:

join()

joinx()^{^[803]}^{^[804]}

Description:

Join up synchronously segmented cluser cursors.

Syntax:

joinx(cs_i:F_i,x_i,..;…)

Note:

Suppose that the joining fields/expressions x_i are ordered in an ascending order, the function joins up multiple synchronously segmented cluster cursors according to the condition that the values of the joining fields/expressions x_iand x₁are equal to generate a cluster cursor consisting of fields F_i,…. Parameter F_iis a referencing field that references records of the cs_i, the sequence of the original cluster cursors. Join up the cluster cursors by primary keys when parameter x_jis absent; and by the values of x_jwhen the parameter is present but no dimensions are set. The function supports cluster multicursors that should contain the same number of subcursors. The join operation is performed by matching the joining field x₁in cs₁with the values of all the other joining fields/expressions, which means it is a one-to-many relationship. The to-be-joined cursors should be stored in one node; cross-node retrieval isn’t allowed.

Options:

@f	Full join; use null to correspond when there is no matching value
@1	Left join; the option is number 1 instead of letter l
@p	Join by positions; ignore parameter x_j

Parameters:

F_i	The resulting field
cs_i	To-be-joined cluster cursors
x_i	Joining field/expression

Return value:

Synchronously distributed cluster cursor

Example:

	A	B
1	[192.168.0.114:8281,192.168.18.131:8281]		A cluster of two nodes
2	=file@0z("salespart.ctx", A1)	=file@0z("orderpart.ctx", A1)	Composite tables salespart.ctx and orderpart.ctx are stored on the two nodes by segments
3	=A2.create()	=B2.create()	Open the two composite tables respectively
4	=A3.cursor()	=B3.cursor()	Generate cluster cursors for the two cluster compositetables respectively
5	=B4.sortx(EID; A4)	=joinx(A4:s,EID;A5:o,EID)	A5 sorts B4’s result, distributes it according to the distribution way of salespart.ctx and generate a cursor for it; B5 joins up the two synchronously distributed cluster cursors

	A
1	=file@n("D:/t1.ctx","192.168.0.111:8281")
2	=A1.create()	Open cluster composite table t1.ctx
3	=A2.cursor@m(;;3)	Generate a synchrounous 3-parts multicursor from A2’s cluster composite table
4	=file@n("D:/t2.ctx","192.168.0.111:8281")
5	=A4.create()	Open cluster composite table t2.ctx
6	=A5.cursor(;;A3)	Synchronously segment A5 according to A3’s multicursor
7	=joinx(A3:t1,EID;A6:t2,EID).fetch()	Join up A3 and A6 to perform a multithreading computation

cs.joinx()[805][806]

Description:

Join up a cursor and a segmentable bin file by the foreign key.

Syntax:

cs.joinx(C:…,f:K:…,x:F,…;…;…;n)

Note:

The function matches the foreign key fields C,… in cursor cs with the key K in segmentable bin file f, which is ordered by K, to find the corresponding record in f, and makes the record’s expression x a new field F and adds it to cs to generate a new cursor. The value corresponding to a mismatched record will be recorded as null.

Options:

@i	Discard the records whose foreign key values can’t be matched
@o(F;…)	Generate a new record by adding a F field whose values are referenced records; expression x can be represented by ~, which means a record
@d	When parameters x:F are absent, discard the records whose foreign key values are matching
@q	Speed up the matching action according to a certain order when the cursor contains a relatively small amount of data or it is a sequence
@c	Speed up the matching action if the cursor is ordered by the first foreign key field; can work with @q option
@u	Speed up the matching operation by shuffling records in the cursor

Parameters:

cs	A cursor/multicursor
C	cs’s foreign key
f	A bin file
K	The bin file’s key; it is treated as row number when written as #
x	An expression of the field of f
F	Name of the field of expression x
n	Number of buffer rows

Return value:

A cursor

Example:

	A
1	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Return a data retrieval cursor:
2	=file("D:\\joinx.btx")	Return a bin file:
3	=A1.joinx(EID,A2:EMPLOYEEID,BONUS+1:SALARY1)	Normal join; use null to represent the records whose foreign key values are mismatched
4	=A3.fetch()
5	=A1.joinx@i(EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Discard the records whose foreign key values are mismatched
6	=A5.fetch()
7	=A1.joinx@i(EID,A2:EMPLOYEEID;5)	The result when parmeters x:F are absent when @i option works:
8	=A7.fetch()
9	=A1.joinx@o(F1;EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Use the original records as values of the new field F1
10	=A9.fetch()
11	=A1.joinx@o(F1;EID,A2:EMPLOYEEID,~:SALARY1;5)	Use ~ to represent parameter x
12	=A11.fetch()
13	=A1.joinx@d(EID,A2:EMPLOYEEID;5)	Keep records whose foreign key values are mismatched when parameters x:F are absent
14	=A13.fetch()
15	=A1.joinx@q(EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Retrieve corresponding records from the bin file in order to match with the foreign key
16	=A15.fetch()
16	=A1.joinx(EID,A2:#1,BONUS+1:SALARY1)	#1 represents the field whose number is 1, which is EMPLOYEEID here
17	=A16.fetch()

cs.joinx()[807][808]

Description:

Join up a cursor and an entity table by the foreign key.

Syntax:

cs.joinx(C:…,T:K:…,x:F,…;…;…;n)

Note:

The function matches the foreign key fields C,… in cursor cs with the key K in entity table T, which is ordered by K, to find the corresponding record in T, and makes the record’s expression x a new field F and adds it to cs to generate a new cursor. The value corresponding to a mismatched record will be recorded as null. Parameter n is the number of buffer rows.

Options:

@i	Discard the records whose foreign key values can’t be matched
@o(F;…)	Generate a new record by adding a F field whose values are referenced records; expression x can be represented by ~, which means a record
@d	When parameters x:F are absent, discard the records whose foreign key values are matching
@q	Speed up the matching action according to a certain order when the cursor contains a relatively small amount of data or it is a sequence
@qc	Speed up the matching action if the cursor is ordered by the first foreign key field
@u	Speed up the matching operation by shuffling records in the cursor

Parameters:

cs	A cursor/multicursor
C	cs’s foreign key
T	An entity table/composite table cursor
K	The entity table’s key; it is treated as row number when written as #
x	An expression of the field of T
F	Name of the field of expression x
n	Number of buffer rows

Return value:

A cursor

Example:

	A
1	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Return a data retrieval cursor:
2	=file("D:\\PERFORMANCE3.ctx")
3	=A2.create()	Open an entity table:
4	=A1.joinx(EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Normal join; use null to represent the records whose foreign key values are mismatched
5	=A4.fetch()
6	=A1.joinx@i(EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Discard the records whose foreign key values are mismatched
7	=A6.fetch()
8	=A1.joinx@d(EID,A3:EMPLOYEEID;5)	Keep records whose foreign key values are mismatched when parameters x:F are absent
9	=A8.fetch()
10	=A1.joinx@o(F1;EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Use the original records as values of the new field F1
11	=A10.fetch()
12	=A1.joinx@o(F1;EID,A3:EMPLOYEEID,~:SALARY1;5)	Use ~ to represent parameter x
13	=A12.fetch()
14	=A1.joinx@q(EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Retrieve corresponding records efficiently from the entity table in order to match with the foreign key
15	=A14.fetch()
16	*=demo.cursor("select from PERFORMANCE")**	Return a cursor
17	=file("D:/employees.ctx").create().cursor()	Return a composite table cursor
18	=A16.joinx(EMPLOYEEID,A17:EID,Name).fetch()	Join a cursor and a composite table cursor via the foreign key
19	=A1.joinx(EID,A3:#1,BONUS+1:SALARY1;5)	#1 represents the field whose number is 1, which is EMPLOYEEID here
20	=A19.fetch()

ch.joinx()[809][810]

Description:

Join up a channel and a bin file or an entity table by the foreign key.

Syntax:

ch.joinx(C:…,f:K:…,x:F,…;…;…;n) Match C,… field in channel ch with key K of the segmentable bin file f to find the corresponding records in f

ch.joinx(C:…,T:K:…,x:F,…;…;…;n) Match C,… field in channel ch with key K of the entity table T to find the corresponding records in T

Note:

The function matches the foreign key fields C,… in channel ch with the key K in bin file f or entity table T, which is ordered by K, to find the corresponding record in f /T, and makes the record’s expression x a new field F and adds it to ch to generate a new channel. The value corresponding to a mismatched record will be recorded as null. Parameter n is the number of buffer rows.

Options:

@i	Discard the records whose foreign key values can’t be matched
@o(F;…)	Generate a new record by adding a F field whose values are referenced records; expression x can be represented by ~, which means a record
@d	When parameters x:F are absent, discard the records whose foreign key values are matching
@q	Speed up the matching action according to a certain order when the channel contains a relatively small amount of data or it is a sequence
@qc	Speed up the matching action if the channel is ordered by the first foreign key field
@u	Speed up the matching operation by shuffling records in the channel

Parameters:

ch	A channel
C	ch’s foreign key
f	A bin fiel
T	An entity table
K	The bin file/entity table’s key
x	An expression of the field of f/T
F	Name of the field of expression x
n	Number of buffer rows

Return value:

Channel

Example:

Bin file:

	A
1	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Return a data retrieval cursor:
2	=file("D:\\joinx.btx")	Return a bin file:
3	=channel()	Create a channel
4	=channel()
5	=channel()
6	=channel()
7	=channel()
8	=channel()
9	=A1.push(A3,A4,A5,A6,A7,A8)	Join cursor A1 to channels A3, A4, A5, A6, A7 and A8, and be ready to push data into the channels
10	=A3.joinx(EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Normal join; use null to represent the records whose foreign key values are mismatched
11	=A4.joinx@i(EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Discard the records whose foreign key values are mismatched
12	=A5.joinx@o(F1;EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Use the original records as values of the new field F1
13	=A6.joinx@o(F1;EID,A2:EMPLOYEEID,~:SALARY1;5)	Use ~ to represent parameter x
14	=A7.joinx@d(EID,A2:EMPLOYEEID;5)	Keep records whose foreign key values are mismatched when parameters x:F are absent
15	=A8.joinx@q(EID,A2:EMPLOYEEID,BONUS+1:SALARY1;5)	Retrieve corresponding records from the bin file in order to match with the foreign key
16	=A1.fetch()	Push data in cursor A1 into the channels
17	=A3.result().fetch()
18	=A4.result().fetch()
19	=A5.result().fetch()
20	=A6.result().fetch()
21	=A7.result().fetch()
22	=A8.result().fetch()

Entity table:

	A
1	=demo.cursor("select EID,NAME,DEPT,SALARY from EMPLOYEE where EID<10 order by EID" )	Return a data retrieval cursor:
2	=file("D:\\PERFORMANCE3.ctx")
3	=A2.create()	Open an entity table:
4	=channel()	Create a channel
5	=channel()
6	=channel()
7	=channel()
8	=channel()
9	=channel()
10	=A1.push(A4,A5,A6,A7,A8,A9)	Join cursor A1 to channels A3, A4, A5, A6, A7 and A8, and be ready to push data into the channels
11	=A4.joinx(EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Normal join; use null to represent the records whose foreign key values are mismatched
12	=A5.joinx@i(EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Discard the records whose foreign key values are mismatched
13	=A6.joinx@o(F1;EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Use the original records as values of the new field F1
14	=A7.joinx@o(F1;EID,A3:EMPLOYEEID,~:SALARY1;5)	Use ~ to represent parameter x
15	=A8.joinx@d(EID,A3:EMPLOYEEID;5)	Keep records whose foreign key values are mismatched when parameters x:F are absent
16	=A9.joinx@q(EID,A3:EMPLOYEEID,BONUS+1:SALARY1;5)	Retrieve corresponding records from the entity table in order to match with the foreign key
17	=A1.fetch()	Push data in cursor A1 into the channels
18	=A4.result().fetch()
19	=A5.result().fetch()
20	=A6.result().fetch()
21	=A7.result().fetch()
22	=A8.result().fetch()
23	=A9.result().fetch()

json()[811][812]

Description:

Parse a string, a record or a table sequence in JSON format.

Syntax:

json(x)

Note:

If parameter x is a JSON string, the function parses it into a table sequence to return; if parameter x is a record or a table sequence, the function parses it into a JSON string to return.

Parameters:

x	A JSON string/record/sequence

Return value:

A table sequence/JSON string

Example:

1	{name:'China',province:[{name:'Heilongjiang',cities: {city:['Harbin','Daqing']}},{name:'Guangdong', cities:{city:['Guangzhou','Shenzhen','Zhuhai']}},{name:'Taiwan',cities: {city:['Taipei','Kaohsiung']}},{name:'Xinjiang',cities:{city:['Urumqi']}}]}
2	=json(A1)	A1 is a JSON string, which is parsed into a table sequence and return the result:
3	=demo.query("select EID,NAME,SURNAME from EMPLOYEE")
4	=json(A3)	A3 is a table sequence, which is parsed into a JSON string and return the result:

k()[813][814]

Description:

Generate a serial byte with a specified number of bytes.

Syntax:

k(n:l)	Generate a serial byte with the length of l bytes from the integer n
k(n_i,…)	Generate a serial byte where byte values are n_i,…

Note:

The function generates a serial byte (Sbyte) with a specified number of bytes. A SByte is an integer made up of byte values and can have a maximum length of 8 bytes. It is used to represent key values. Two SBytes with the same length are comparable, but can’t be computed.

Parameters:

n	An integer
l	The length of bytes with 1 being the default value; the max value is 8
n_i	Byte value

Return value:

A serial byte value

Example:

=k(1)	1; generate a serial byte value whose length is one byte from integer 1
=k(256:1)	Generate a serial byte value whose length is 1 byte from integer 256; since 256 occupies more than one byte, error will be reported:Out-of-bound index
=k(256:2)	256; generate a serial byte value whose length is two bytes from integer 256
=k(1,2,3)	66051

k{}[815][816]

Description:

Get certain bytes from a serial byte to form a new serial byte value.

Syntax:

k{a,…,b:c,…}

Note:

The function gets certain bytes a,…,b:c,… from a serial byte k to form a new serial byte value. {} can only use constants.

Parameters:

A serial byte value

The a^th byte of a serial byte

b:c

The bytes from the b^th position to the c^th position in a serial byte

Return value:

A serial byte

Example:

=k(4,5,6,8){2}			5; get the second byte from serial byte value k(4,5,6,8) to generate a singe-byte serial byte value
=k(4,5,6,8){1:3}			263430; get the bytes from 1 to 3 from serial byte value k(4,5,6,8) to generate a new serial byte value
=k(4,5,6,8){1,2,3}			263430; get the first 3 bytes from serial byte value k(4,5,6,8) to generate a new serial byte value
=k(4,5,6,8){1,2:3}			263430; get the first byte and the next two bytes from serial byte value k(4,5,6,8) to generate a new serial byte value
=k(1,2,3,4,5,6,7){1,2:3,5,6}			4328719622 get the first, the 2^nd and 3^rd, and the 5^th and the 6^th bytes from serial byte value k(1,2,3,4,5,6,7) to generate a new serial byte value

		A
	1	=create(k1,v1).record([k(1000:3),110000,k(223332:3),2045803,k(31121:3),90730,k(453384:3),78940,k(231410:3),100])		Create a table sequence
	2	=file("D:/ckv.ctx")		The composite table file
	3	=A2.create(#k1:3,v1;k1:3)		Create the composite table’s base table where key k1 is the serial byte data whose length is 3
	4	=A3.append(A1.cursor())		Append cursor records to the base table
	5	=A3.cursor(k1).fetch()		Return data of column k1 in the base table
	6	=A3.cursor(k1{1}).fetch()		Get the serial bytes of the fist bytes of k1’s values
	7	=A3.cursor(k1{2}).fetch()		Get the serial bytes of the second bytes of k1’s values
	8	=A3.cursor(k1{2:3}).fetch()		Get the serial bytes of the second and third bytes of k1’s values

kafka_close()[817][818]

Description:

Close a Consumer connection.

Syntax:

kafka_close (fd)

Note:

The function closes a Consumer connection to release resources.

Parameter:

fd	A consumer object

Example:

	A
1	=kafka_subscribe("D:/kafka_string.properties";"topic-test";"String","byte[]")	Connect to Kafka server
2	=kafka_close(A1)	Close connection to Kafka server

kafka_commit()[819][820]

Description:

Commit the current consumer offset position.

Syntax:

kafka_commit (fd)

Note:

By default, the function commits the real-time consumer offset position.

Parameters:

fd	A consumer object

Example:

	A
1	=kafka_subscribe("D:/kafka_string.properties";"topic-test";"String","byte[]")	Connect to Kafka server
2	=kafka_poll(A1)	Get records from topic test1
3	=kafka_commit(A1)	Commit the current consumer offset

kafka_poll()[821][822]

Description:

Return records in a Consumer topic as a table sequence.

Syntax:

kafka_poll (fd, timeout)

Note:

The function gets records of the current Consumer topic.

Parameters:

fd	A Consumer object
timeout	The interval of consumer poll loop; default is 1000ms

Options:

@c	Enable a cursor-based query

Return value:

Table sequence or cursor

Example:

	A
1	=kafka_subscribe("D:/kafka_string.properties";"topic-test";"String","byte[]")	Connect to Kafka server
2	=kafka_poll(A1)	Get records from topic test1
3	=kafka_poll@c(A1)	Get records from topic test1 with cursor

kafka_subscribe()[823][824]

Description:

Connect to Kafka server.

Syntax:

kafka_subscribe (prop:value,....;topic,...;keyType, valueType)

kafka_subscribe (filename or fileObject; topic,...; keyType, valueType)

Note:

The function connects to the Kafka server, and inputs the property parameter properties in the form of k:v, or stores properties as a configuration file suffixed with .properties.

Parameters:

prop:value	The property parameter Properties, which will be input in the form of k:v and which can include multiple property parameters; refer to Kaka documents to learn more about this
topic	Query a topic or multiple topics
keyType	The data type of a Consumer key, which is by default the string; it supports int, integer, float, long and string
filename	The property parameter file suffixed with .properties
fileObject valueType	A file object The data type of a Consumer key, which is by default the string; it supports int, integer, float, long and string

Return value:

A Consumer object

Example:

	A
1	=kafka_subscribe("D:/kafka_string.properties";"test1";"String","byte[]")	Connect to Kafka server through the configuration file kafka_string.properties where the topic is test1, key is String, and value is byte[]
2	=kafka_subscribe(file("D:/kafka_string.properties");"test1";"String","byte[]")	Connect to Kafka server through the configuration file object, with the rest of the settings being same as the above
3	=kafka_subscribe("bootstrap.servers":"192.168.0.144:9092","zookeeper.connect":"192.168.0.144:2181", "group.id":"test","zookeeper.session.timeout.ms":"4000","zookeeper.sync.time.ms":"200", "auto.commit.interval.ms":"500","auto.offset.reset":"latest", "serializer.class":"kafka.serializer.StringEncoder", "key.deserializer":"org.apache.kafka.common.serialization.StringDeserializer", "value.deserializer":"org.apache.kafka.common.serialization.ByteArrayDeserializer"; "test1";"String","byte[]")	Connect to Kafka server through a parameter, with the rest of the settings being same as the above

key()[825][826]

Here’s how to use key() function.

r.key()[827][828]

Description:

Get the primary key value of a record.

Syntax:

r.key(F_i,…)

Note:

The function gets the primary key value of record r according to key F_i. If F_i is omitted, return the whole primary key value. If the key isn’t set for r, return null. If it is a one-field key, just return the single key value; and with a composite key, return a sequence of values.

Parameters:

r	A record
F_i	Key

Return value:

A record’s primary key

Example:

	A
1	*=demo.query("select from EMPLOYEE ")**
2	=A1(1).key()	1; return null because A1 doesn’t set a key
3	=A1.keys(EID)	Set EID field as the key
4	=A1(1).key()	1; return the primary key value of the first record
5	=A1.keys(EID,DEPT)	Set EID&DEPT fields as the key
6	=A1(1).key()	[1,R&D]; the primay key value is a sequence because the key consist of two fields
7	=A1(1).key(DEPT)	R&D; get the value of a specified key field

Related functions:

T.keys()

v.v()

keys()[829][830]

Here’s how to use keys() function.

T.keys()[831][832]

Description:

Set a key for a table sequence.

Syntax:

T.keys(K_i,…)

Note:

The function sets K_i,… as the key of the table sequence T. The absence of the parameter will clear the key. A T.create() operation will copy the key at the same time.

Parameters:

T	A table sequence
K_i	Key

Return value:

A table sequence with a key

Example:

	A
1	=demo.query("select EID,NAME,DEPT,SALARY from EMPLOYEE order by EID asc,DEPT asc")
2	=A1.keys(EID,DEPT)	Set EID&DEPT fields as A1’s key
3	=A1(1).key()	[1,R&D]
4	=A1.keys()	Remove the ky
5	=A1(1).key()	Return null because A1 doesn’t set a key
6	=A1.keys(EID,DEPT)
7	=A1.create()	Copy the key since table sequence T has one
8	=A7.insert(0,1,"Jack","HR",3000)
9	=A8(1).key()	[1,HR]

Related functions:

r.key()

v.v()

T.keys(Ki,…)[833][834]

Description:

Define the key(s) for a memory table.

Syntax:

T.keys(Ki,…)

Note:

The function defines the key(s) Ki,… for memory table T.

Parameters:

Ki	Key name; can be one or multiple keys; delete all keys of a memory table when the parameter is absent
T	A memory table

Return value:

A memory table

Example:

	A
1	=demo.cursor("select EID,NAME,GENDER from EMPLOYEE where EID<10")	Return cursor of the retrieved data
2	=A1.memory()	Return a memory table
3	=A2.keys(EID,NAME)	Set EID and NAME as the memory table’s keys
4	=A3(1).key()	Get the keys of the first record and return the result:
5	=A2.keys()	Delete all keys of the memory table
6	=A3(1).key()	Query the keys of the first record and return null

T.keys(Ki,…;n)^{^[835]}^{^[836]}

Description:

Create an index over a primary key when the latter is set.

Syntax:

T.keys(Ki,…;n)

Note:

The function set primary key Ki,... for table sequence/memory table T and, in the meantime, create an index over the key. To create a hash index, one of @i option and parameter n should be present. To create a serial byte index, omit parameter n. When both @s option and parameter n exist, ignore the option.

Parameters:

Ki	Primary key, which can be one or multiple; delete all keys of a memory table when this parameter is absent
T	A table sequence/memory table
n	An integer greater than 1, which is length of the hash table; its default lenght is the table length. Will be omitted when creating a serial byte index with @s option

Options:

@i	Create a hash index
@s	Create a serial byte index for a serial byte primary key; omit parameter n when using this option

Return value:

A table sequence/memory table

Example:

	A
1	=demo.query("select EID,NAME,DEPT,SALARY from EMPLOYEE")
2	=A1.keys(EID,DEPT;1)	Set EID,DEPT as A1’s primary key and create a hash index for it; length of the hash is 1
3	=A1.keys@i(EID,DEPT)	Same as A2
4	=A1.keys@i(EID,DEPT;1)	Same as A2
5	=A1.keys@s(EID)	Set EID as A1’s primary key and create a serial byte index over the key
6	=A1.keys@s(EID;1)	Set EID as A1’s primary key and create a hash index whose length is 1 for the key; ignore @s option since parameter n is present

lcm()[837][838]

Description:

Return the least common multiple.

Syntax:

lcm(x_i,…)

lcm(A)

Note:

The function gets the least common multiple of the numeric members of [x₁, x₂,…]. If there is any member that is equal to or less than 0, than the lcm function returns the false value 0

Parameter:

A	A sequence
x_i	An expression, which will be ignored if its value is not a number

Return value:

The least common multiple

Example:

lcm(5,2)

left()[839][840]

Description:

Get a substring starting from the leftmost side of a string.

Syntax:

left(string,n)

Note:

The function gets a substring with the length of n starting from the leftmost side of string string. If n<0, the substring’s length is the sum of source string’s length and the value of n.

Parameters:

string	The source string from which the substring is obtained
n	The length of the substring

Return value:

A string

Example:

left("abcdefg",3)	"abc"
left("abcdefg",-3)	"abcd"

Related functions:

mid()

right()

len()[841][842]

Here’s how to use len() function.

A.len()[843][844]

Description:

Get the length of a sequence.

Syntax:

A.len()

Note:

The function gets the length of sequence A.

Parameters:

A	Sequence object

Return value:

An integer

Example:

	A
1	=[1,2,4]
2	=A1.len()	3
3	=["a","b"].len()	2
4	=[]
5	=A4.len()	0

k.len()[845][846]

Description:

Get the length of a serial byte.

Syntax:

k.len()

Note:

The function returns the length of serial byte k, which is the number of bytes in k.

Parameters:

k	A serial byte

Return value:

An integer

Example:

k(2).len()	1
k(256:2).len()	2
k(1,2,3).len()	3

T.len()[847][848]

Description:

Get the number of records in a memory table.

Syntax:

T.len()

Note:

The function gets the number of records in memory table T.

Parameters:

T	A memory table

Return value:

An integer

Example:

	A
1	=demo.query("select EID,NAME,GENDER from employee where EID< 10").cursor()	Return cursor of retrieved data
2	=A1.memory()	Return a memory table
3	=A2.len()	9

len()[849][850]

Description:

Compute the length of a string.

Syntax:

len(s,cs)

Note:

The function computes the length of a string. The default charset is GB2312; calculate the string’s length in Unicode if parameter cs is absent.

Parameters:

s	String for which you want to compute the length
cs	Charset; can be omitted

Return value:

An integer

Example:

len("esproc")	6
len(" esproc ")	8
len("esproc",)	6
len("esproc","UTF-8")	6

lg()[851][852]

Description:

Compute the logarithm to base 10.

Syntax:

lg(numberExp)

Note:

The function computes numberExp’s logarithm to base 10.

Parameters:

numberExp

Data for which you want to compute the logarithm to base 10

Return value:

Numeric value

Example:

lg(54)

1.7323937598229684

Related functions:

ln()

like()[853][854]

Description:

Find if a string matches a format string.

Syntax:

like(stringExp, formatExp)

Note:

The function checks if the string stringExp matches the format string formatExp. In the formate string, the symbol asterisk "*" matches 0 or multiple characters; and the question mark "?" matches a single character. An escape character is used to make "*" match the character itself, for example, \* is escaped to * and \\ to \.

Parameters:

stringExp	A string expression
formatExp	A format string expression

Option:

@c	It makes the matching case-insensitive, while the default is case-sensitive.

Return value:

Boolean value

Examples:

like("abc123", "abc*")	true
like("abc123", "abc1?3")	true
like("abc123", "abc*34")	false
like("abc123", "ABC*")	false
like@c("abc123", "ABC*")	true
like ("abc123", "abc\")	true
like("abc123", "abc\\*")	true abc\\ is escaped to abc\

ln()[855][856]

Description:

Compute the natural logarithm of the parameter.

Syntax:

ln(numberExp)

Note:

The function computes the natural logarithm of parameter numberExp.

Parameters:

numberExp

Data for which you want to compute the natural logarithm

Return value:

Numeric value

Example:

ln(54)

3.9889840465642745

Related functions:

lg()

lock()^{^[857]}^{^[858]}

Description:

Use a synchronization lock.

Syntax:

lock(n,s)

Note:

The function enforces limits on access to a file in an multithreading execution environment using lock-based synchronization. With the lock, only one thread can access and process the file at a time.

Parameters:

n	Lock name
s	Timeout (in millisecond); waiting to be locked if the parameter is absent

Options:

@u	Unlock the restriction

Return value:

Lock name

Example:

Locking:

	A
1	=lock(1)	Use a lock named 1
2	>output("Task "/arg1/" start...")	Output the parameter and start to calcualte
3	=file("D:/file/test/1.btx")	Create a btx file
4	=create(ID,Value)	Create a table sequence
5	*>A4.record([arg1,arg1arg1])**	Add records to A4’s table sequence
6	>sleep(1000)	Make the system sleep for 60s
7	>A3.export@ab(A4)	Write A4’s table sequence into the btx file
8	>output("Task "/arg1/" finished.")	Output the parameter and finish the calculation
9	>lock@u(1)	Unlock the access restriction

File access:

	A
1	=file("D:/file/test/1.btx")
2	D:\test\December’s esProc release \lock1.dfx
3	=callx(A2,to(100))	When using callx() function to acess a file, the max number of parallel task set in Tool -> Options should be greater than 1 in case that the lock-based synchronization reports an error
4	=A1.import@b()

long()[859][860]

Description:

Convert a string or a number to a 64-bit long integer.

Syntax:

long(stringExp)

long(numberExp)

Note:

The value of parameter stringExp must be a string that consists of a long integer which has 64 bits or less. For a value with more than 64 bits, the result of long(stringExp) is imprecise and its decimal part, if any, will be truncated.

The value of parameter numberExp must be a long integer which has 64 bits or less. For a value with more than 64 bits, the result of long(numberExp) is imprecise.

Parameters:

stringExp	The string expression you want to convert as a long integer.
numberExp	The number you want to convert as a long integer, whose decimal part, if any, will be truncated.

Return value:

A 64-bit long integer

Examples:

long("1234567")	1234567
long(1234567.789)	1234567

Related functions:

float()

int()

decimal()

number()

string()

lower()[861][862]

Description:

Convert all characters of a string to lower case.

Syntax:

lower(s)

Note:

The function converts all characters of a string to lower case.

Parameters:

s	The string you want to convert to the lower case

Options:

@q	A quoted string won’t be converted

Return value:

A string

Example:

lower("ABCdef")

abcdef

lower("defABC")

defabc

lower@q("\'AD\'")

lower("\'AD\'")

'AD'

'ad'

	A
1	"ABC"
2	=lower@q(A1)	"ABC"

Related functions:

upper()

m()[863][864]

Here’s how to use m() function.

A.m()[865][866]

Description:

Get members at specified positions.

Syntax:

A.m(i)	-n<=i<=n and i is not equal to 0; 1<=i<=n indicates getting the i^th member; -n<=i<=-1 indicates getting the i^th member from the bottom
A.m(P)	P is a non-zero n-integer sequence

Note:

A is a sequence whose length is n, from which you get members at specified positions. The function is generally used to get members reversely from a sequence.

Parameters:

A	A sequence expression
i	An integer
P	A non-zero n-integer sequence

Options:

@r	Turn back if the specified position exceeds the boundary of A, that is, to set i=if(i%n==0,n,i%n), where n is the length of A.
@0	The member represented by a sequence number that exceeds the boundary of A will be excluded from the result.

Return value:

A value or a sequence composed of the members at the specified positions in sequence A

Example:

	A
1	[a,b,c,d,e,f,g,h,i,j]
2	=A1.m(2)	b
3	=A1.m(-2)	i
4	=A1.m([2,3])	[b,c]
5	=A1.m([-2,-3])	[i,h]
6	=A1.m@0([5,12])	[e]
7	=A1.m@r([5,12])	[e,b]

Related functions:

A.p()

A.m(a:b,c,d:e)[867][868]

Description:

Get members of a sequence at specified positions to form a new sequence.

Syntax:

A.m(a:b,c,d:e)

Note:

A is a sequence whose length is n, from which you get members at specified positions to form a new sequence, with the condition -n<=a<=n & a!=0. If 1£a£n, it is the a^th member of sequence A when counted from left to right; if -n£ a £-1, it is the a^th member of sequence A when counted from right to left. The rules also apply to b, c, d, and e. So the function is ofent used to get members reversely from a sequence. The members a and d represent must be respectively on the left side of the members b and e designate. When the parameter on the left side of the colon is omitted, the default value is 1; when the parameter on the right side of the colon is omitted, the default value is -1.

Parameters:

A	A sequence
a	An integer; 1 by default
b	An integer; -1 by default
c	An integer
d	An integer; 1 by default
e	An integer; -1 by default

Return value:

A sequence

Example:

	A
1	=to(1,100).m(1:3,9,97:)	[1,2,3,9,97,98,99,100]
2	=to(1,100).m(:5,-1,66:-32)	[1,2,3,4,5,100,66,67,68,69]

max()[869][870]

Here’s how to use max() function.

A.max()[871][872]

Description:

Compute the maximum value of all the non-null members in a sequence.

Syntax:

A.max()

Equivalent to max(x₁,…,x_n)

Note:

The function computes the maximum value of all the non-null members in sequence A. Note that this function doesn’t apply to a sequence whose members are not of the same data type.

Parameters:

A	A sequence

Return value:

The maximum value of all members in sequence A

Example:

	A
1	=[8,-6,1,3,5].max()	8
2	=["c","b","e","A"].max()	"e"
3	=["a",1].max()	Error message is displayed because the members are of different data types
4	=["a",null,"b"].max()	"b"
5	=max(8,-6,1,3,5)	8

Related functions:

A.max(x)[873][874]

Description:

Compute x with each member of the sequence and then find the maximum value of the members of the new sequence.

Syntax:

A.max(x)

Equivalent to A.(x).max()

Note:

The function loops through members of sequence A and returns the maximum value among members of the new sequence.

Parameters:

A	A sequence
x	Generally an expression of a single field name, or a legal expression composed of multiple field names

Return value:

The maximum value of members of a new sequence obtained by performing computations on members of sequence A.

Example:

	A
1	*=demo.query("select from EMPLOYEE")**
2	=A1.max(SALARY)	Compute the highest salary
3	=A1.(SALARY+100).max()	Add 100 to the salary of each employee and then compute the highest salary

Related functions:

A.max()

maxp()[875][876]

Here’s how to use maxp() function.

A.maxp()[877][878]

Description:

Get the member of a sequence that makes the maximum value for the expression.

Syntax:

A.maxp(x)

Note:

The function computes expression x with each member of sequence A and returns the member which makes the maximum value for expression x.

Options:

@1	Return the first member that fulfills the condition.
@a	Return all the members that fulfill the condition. By default, return what @1 gets.
@z	Search the member from back to front

Parameters:

A	A sequence
x	The expression to be computed

Return value:

The member which makes the maximum value for the expression x

Example:

	A
1	[2,5,4,3,2,1,4,1,3]
2	=A1.maxp(~*~)	5, @1 is the default option
3	=A1.maxp@a(~*~)	[5]
4	=A1.maxp@z(~*~)	5
5	=A1.maxp@az(~*~)	[5]
6	=demo.query("select EID,NAME,BIRTHDAY from EMPLOYEE")
7	=A6.maxp(BIRTHDAY)

Related functions:

A.pmax()

A.minp()

mcursor()[879][880]

Here’s how to use mcursor() function.

CS.mcursor()[881][882]

Description:

Generate a multicursor based on a sequence of cursors.

Syntax:

CS.mcursor()

Note:

The function generates a multicursor based on CS, a sequence of cursors. Every cursor in the cursor sequence must have the same structure. A multi-multicursorwill be generated if CS is a sequence of multicursor.

Parameters:

CS	A sequence of cursors

Return value:

Multicursor

Example:

test_mcs.dfx is the deployment file for deploying remote node servers. The nodes are 【"192.168.0.204"," 192.168.0.205","192.168.0.206"】; their port numbers are 8081. Below is the file:

	A
1	*=connect("demo").cursor("select from SCORES where SUBJECT=?",arg1)**
2	return A1

	A
1	=callx("test_mcs.dfx",["English","Math","PE"];["192.168.0.204:8081","192.168.0.205:8081","192.168.0.206:8081"])	Each of the three parallel nodes returns a cursor to form a cursor sequence
2	=A1.mcursor()	Generate a multicursor based on the cursor sequence
3	=A2.fetch()	Fetch all records from the multicursor

cs.mcursor()[883][884]

Description:

Generate a multicursor based on one cursor.

Syntax:

cs.mcursor(n)

Note:

The function generates a multicursor based on cursor cs, from which data is fetched and stored in n subcursors. If n isn’t set, the default value is the number of parallel tasks set in Tool>Options.

Parameters:

cs	A single cursor
n	An integer

Return value:

Multicursor

Example:

	A
1	*=demo.cursor("select from EMPLOYEE")**
2	=A1.mcursor(3)	Create a multicursor

md5()^{^[885]}^{^[886]}

Description:

Return a string’s MD5 signature.

Syntax:

Md5(s)

Note:

The function returns string x’s MD5 signature. MD5 is a widely used hash function producing a hash value.

Parameters:

A string

Return value:

A string

Example:

md5("abced")

median()^{^[887]}^{^[888]}

Here’s how to use median() function.

A.median(k:n)^{^[889]}^{^[890]}

Description:

Divide a sequence into multiple segments and return the specified bordering member(s).

Syntax:

A.median(k:n)	Divide sequence A into n segments evenly according to its length and return the bordering member between the k^th segment and the (k+1)^th segment
A.median(k:n,x)	Calculate expression x over each member of sequence A to generate a new sequence in ascending order, then divide the new sequence into n segments evenly according to its length and return the bordering member between the k^th segment and the (k+1)^th segment

A.median(k:n)

Note:

The function returns a sequence of the bordering members between every two segments when parmeter k is absent but parameter n is present.

Parameter x should always be present. When prameters k,n are absent, if the length of the sequence is an odd, return the median member value; if it is an even, return the average value of the two members in the middle. Perform a logical division if the length of the sequence is indivisible.

Parameters:

A	A sequence
k	The k^th segment (1=<k<=n); return the bordering members of between every two segments as sequence when k is absent
n	The number of to-be-divided segments, which is greater than 1 and whose default is 2; can be omitted when parmeter k is absent
x	An expression

Return value:

A number or a sequence

Example:

	A
1	=[1,2,3,4,5,6,7,8]
2	=A1.median()	As all parameters are absent and the length of the sequence is an even number, the function returns the average of the two members in the middle, that is (4+5)/2=4.5
3	=A1.median(2:3)	The sequence is divided as follows: Divide the sequence into 3 segments and return the bordering member between the second segment and the third on, which is 6
4	=A1.median(:3)	As no segment is specified, return the bordering members between every two segments as a sequence, which is [3,6]
5	=A1.median(:10)	The sequence is divided as follows: Result: [1,2,3,4,4.5,5,6,7,8]
6	=A1.median(:,~%2)	Divide each member of sequence A1 by 2 and get the remaider to generate a new sequence in ascending order: [0,0,0,0,1,1,1,1]; As prameters k,n are absent and the the length of the sequence is an even, the function returns the average value of the two members in the middle: (0+1)/2=0.5
7	A1.median(2:3,~%2)	Divide the new sequence evenly into 3 segments and return the bordering member between the 2^nd and the 3^rd : 1

memory()[891][892]

Here’s how to use memory() function.

cs.memory(K,…)^{^[893]}^{^[894]}

Description:

Generate a memory table from a cursor.

Syntax:

cs.memory(K,…)

Note:

The function generates a memory table, whose key is K, from a cursor. When parameter K is absent, the newly-generated memory table will inherit the cursor’s key.

Parameters:

K	The key; can be omitted
cs	A cursor

Options:

@z	Generate a compressed memory table to save space

Return value:

A memory table

Example:

=demo.cursor("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<10")

Return the cursor with retrieved data

=A1.memory(EID)

Return a memory table whose key is EID

cs.memory(K,…)^{^[895]}^{^[896]}

Description:

Generate a cluster memory table from a cluster cursor.

Syntax:

cs.memory(K,…)

Note:

According to cluster cursor cs, the function generates a cluster memory table that distributed the same way as cs and whose key is K. If cs is a cluster multicursor, load a series of cursors in order.

Parameters:

K	The key; can be omitted
cs	A cluster cursor

Return value:

A cluster memory table

Example:

	A
1	=file@n("D:/test0.ctx","169.254.121.62:8281")	Open a duplicate file
2	=A1.create()	Create a duplicate cluster table
3	=A2.attach(table)	Retrieve cluster table table
4	=A3.cursor(NAME,GENDER;EID<6)	Get NAME field and GENDER field where EID<6 from cluster table table and return them as a cursor
5	=A4.memory(GENDER)	Generate a cluster memory table whose key is GENDER from a cluster cursor

memory(h,V)^{^[897]}^{^[898]}

Description:

Generate a cluster memory table from a local memory table.

Syntax:

memory(h,V)

Note:

The function generates a cluster memory table from local memory table V, which is stored in a global variable, held in node sequence h.

Parameters:

h	Node sequence
V	A memory table’s global variable

Return value:

Cluster memory table

Example:

Generate a global variable:

	A
1	=file@0("test1.ctx",["192.168.31.72:8281","192.168.31.72:8291"])	Open a cluster file
2	=A1.create()	Open a cluster composite table
3	=A2.memory(;;arg1)	arg1Generate global variable cluster memory table arg1 from A2’s cluster composite table

	A
1	=memory(["192.168.31.72:8281","192.168.31.72:8291"],arg1)	Generate a cluster memory table from the local memory table arg1
2	=A1.cursor().fetch()

T.memory()^{^[899]}^{^[900]}

Description:

Convert a compressed memory table into an uncompressed one.

Syntax:

T.memory()

Note:

The function converts a compressed memory table into an uncompressed one.

Options:

@z	Convert an uncompressed memory table into a compressed one to save memory space

Return value:

A memory table

Example:

	A
1	=demo.cursor("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<10")	Return a cursor containing retrieved data
2	=A1.memory@z(EID)	Return a compressed memory table whose key is EID
3	=A2.memory()	Convert a compressed memory table into an uncompressed one
4	=A3.memory@z()	Convert an uncompressed memory table into a compressed one

T.memory(C,…;w)[901][902]

Description:

Generate a memory table from an entity table.

Syntax:

T.memory(C,…;w)

Note:

The function filters entity table T according to filtering condition w and imports the data into the memory to generate a memory table containing column C. we can handle a memory table as we do to a table sequence. When parameter C,… is absent but parameter w is present, the semicolon before w can’t be omitted. If a column C is preceded by # in the entity table, column C will be the key of memory table T. The memory table inherits the entity table’s key if you don’t set a key for it.

Parameters:

C	A column name; import all columns when the parameter is omitted
w	Filtering condition; won’t perform filtering when the parameter is omitted
T	An entity table in a composite table

Return value:

A memory table

Example:

	A
1	=file("D:\\employees.ctx")	employees is an existing composite table file
2	=A1.create()	Open the composite table
3	=A2.attach(t1)	Return the composite table’s attached table t1
4	=A2.memory()	Generate a memory table using all columns of the base table
5	=A2.memory(EID,Dept,Name;EID<5)	Get some columns where EID<5 from the base table to generate a memory table
6	=A3.memory()	Get all columns from the attached table to generate a memory table

T.memory(C,…;w)[903][904]

Description:

Generate a cluster memory table from a cluster entity table.

Syntax:

T.memory(C,…;w)

Note:

The function generates a cluster memory table from a cluster entity table T, which must have at least one dimension that is used to segment T and facilitates the segmentation. Clear a node’s memory at exit; will perform auto-clear when timeout occurs.

Parameters:

C	A column name; import all columns when the parameter is omitted
w	Filtering condition; won’t perform filtering when the parameter is omitted
T	A cluster composite table’s entity table with dimensions

Return value:

A cluster memory table object

Example:

	A
1	=file@0("emp1.ctx",["192.168.0.116:8281","192.168.0.129:8281"])	Open a duplicate file
2	=A1.create()	Create a duplicate cluster table
3	=A2.attach(t1)	Get cluster table t1
4	=A3.memory(NAME,GENDER;EID<5)	Get columns NAME and GENDER with EID being less than 5 from t1 to generate a memory table

merge()[905][906]

Here’s how to use merge() function.

A.merge()[907][908]

Description:

Merge multiple table sequences/record sequences.

Syntax:

A.merge (x_i,…)

Note:

The function merges multiple table sequences/record sequences A(i)s (which can be represented as A(i)|…) according to the rules of r.v() function when parameter x_i is omitted and primary keys are not set for A, a sequence of table sequences/record sequences. Every A(i) must be of the same structure.

Parameters:

A	Multiple table sequences/record sequences of the same structure
xi	A field of A(i); if performing merge by multiple fields, use the comma to separate them, for example, x₁,x₂...

Options:

	@u		Remove the duplicates from the table sequence/record sequence generated from unioning members of A(i)s in certain order
	@i		Return a table sequence/record sequence composed of the common members of A(i)s
	@d		Generate a new table sequence/record sequence by removing members of A(2)&…A(n) from A(1).
@o		Do not assume that A(i) is already sorted by [x_i,…]
@0		Put records with null values at the end
@x		Remove common members of A(i) and union the other members to generate a new table sequence/sequence

Return value:

Table sequence/record sequence

Example:

	A
1	=demo.query("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<6")	EID field is ordered
2	=demo.query("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID>3")	EID field is ordered
3	=[A1,A2].merge(EID)	Merge A1 and A2 in order by EID field
4	=[A1,A2].merge@u(EID)	Merge A1 and A2 in order by EID field and remove duplicates from the result
5	=[A1,A2].merge@i(EID)	Merge A1 and A2 in order by EID field but only keep records that have duplicates
6	=[A1,A2].merge@d(EID)	Delete A2’s members from A1
7	=[A1,A2].merge@o(SALARY)
8	=[A1,A2].merge@x(EID)	Merge A1 and A2 to get a new sequence by removing their common members
9	=demo.query("select * from EMPLOYEE where GENDER = 'M'").keys(EID)
10	=demo.query("select * from EMPLOYEE where GENDER = 'F'").keys(EID)
11	=[ A9,A10].merge()	With x_i omitted, this table sequence is the result of merge by the order of the primary keys
12	=demo.query("select * from EMPLOYEE where GENDER = 'M' and EID<15")
13	=demo.query("select * from EMPLOYEE where GENDER = 'M' and EID>=15")
14	=[A12,A13].merge(EID,GENDER)	Merge by the EID field and GENDER field
15	=A1.run(EID=null)
16	=[A2,A15].merge(EID)
17	=[A2,A15].merge@0(EID)

Related functions:

CS.mergex()

Mergex()[909][910]

Here is how to use mergex() function.

CS.mergex()[911][912]

Description:

Merge data of the member cursors of a cursor sequence.

Syntax:

CS.mergex(x_i,…)

Note:

CS is a sequence of cursors ordered by [x_i,…], and from each cursor a sequence of records can be output. The function merges the records of these cursors by the expression x_i. Members of the cursor sequence must be of the same structure. If members are multicursors, they must have the same number of parallel cursors and be segmented synchronically.

Parameters:

CS	A sequence of cursors.
x_i	An expression. If perfoming merge by multiple fields, use comma to separate them, for example, x₁,x₂...

Options:

@u	Union operation. Remove the duplicate records from the resulting cursor obtained by unioning the cursor members of CS in certain order. By default the duplicate records are included
@i	Intersection operation. Return a cursor composed of common members of members of CS, the sequence of cursors.
@d	Difference operation. Create a new cursor by removing members of CS2&…CSn from CS1
@0	Put records with null values at the end
@x	Only merge distinct records in member cursors

Return value:

A cursor

Example:

	A		B		C
1	*=demo.cursor("select from STOCKRECORDS")**					Retrieve data and return a cursor
2	For
3		=A1.fetch(500)				Fetch data from the cursor
4		if B3==null		break
5		else
6				=B3.sort(STOCKID)		Sort by STOCKID
7				=file("D:\\"+"a"+string(A2)+".txt").export@t(C6)		Store data retrieved each time in a file.
8				=B1=B1\|file("D:\\"+"a"+string(A2)+".txt")		File object sequence
9	for B1
10		=A9.cursor@t()
11		=C1=C1\|B10				File cursor sequence
12	=C1.mergex(STOCKID)					Merge members of the sequence in order by STOCKID.
13	=A12.fetch()					Get records from the merged cursor
14	=directory@p("D://*.txt")					Below are several txt files:
15	for A14
16			=file(A15).c rsor@t()		=B14=B14\|B16
17	=B14.mergex@i(STOCKID)		=A17.fetch()			Return a cursor composed of their common members, with STOCKID already ordered.
18	=directory@p("D://*.txt")					The txt files are the same as the above
19	for A18
20			=file(A19).cursor@t()		=B18=B18\|B20
21	=B18.mergex@u(STOCKID)		=A21.fetch()			Return a new cursor in which duplicate records have been removed. STOCKID is already ordered.
22	=directory@p("D://* txt")					The txt files are the same as above
23	for A22
24			=file(A23).cursor@t()		=B22=B22\| 24
25	=B22.mergex@d(STOCKID)		=A25.fetch()			A new cursor created by removing from the first cursor the members of the other cursors; STOCKID is already ordered.
26	*=directory@p("D://.txt")**
27	for A26
28			=file(A27).cursor@t()		=B26=B26\|B28
29	=B26.mergex@x(STOCKID)		=A29.fetch()			Get dinstinct recors from the cursors to create a new cursor ordered by STOCKID

Related functions:

A.merge()

cs.mergex()^{^[913]}^{^[914]}

Description:

Merge all parts of a cluster cursor into a local ordinary cursor.

Synatx:

cs.mergex(x_i,…)

Note:

The function merges all parts of a cluster cursor by field expression x_i. Parameter cs is a sequence made up of all parts of a cluster cursor ordered by field expressions [x_i,…]. If cs is multicursor for a composite table and there are no parameters, perform the merge by dimension(s).

Parameters:

cs	A sequence consisting of all parts of a cluster cursor
x_i	A field expression; use the comma to separate multiple expressions if it is a merge by multiple fields, like x₁,x₂...

Return value:

An ordinary cursor

Example:

	A
1	=file@0("emp2.ctx",["127.0.0.1:8282"])	Open a cluster file
2	=A1.create()	Create a cluster composite table
3	=A2.cursor(EID,NAME;EID<8)	Return a part of the cluster cursor
4	=A2.cursor(EID,NAME;EID>495)	Return a part of the cluster cursor
5	=[A3,A4].mergex(EID)	Merge two parts of the cluster cursor in A3 and A4 by EID and return a local ordinary cursor
6	=A5.fetch()

	A
1	[192.168.0.110:8281,192.168.18.143:8281]
2	=file@0("emp.ctx", A1)	Distributed composite table file
3	=A2.create()	Open a cluster composite table
4	=A3.cursor@m(;;3)	Return a cluster multicursor
5	=A4.mergex()	Perform the merge by deminsion as A4 is a multicursor for a composite table and there are no parameters

mcs.mergex()^{^[915]}^{^[916]}

Description:

Merge multicursors into an ordinary cursor.

Syntax:

mcs.mergex(x_i,…)

Note:

The function merges multicursors by field expression x_i. Parameter mcs is a sequence of multicursors ordered by field expressions [x_i,…], in which each member is synchronously segmented and has the same number of segments. When mcs is a sequence of multicursors for a composite table, perform the merge automatically by dimensions.

Parameters:

mcs	A sequence of multicursors
x_i	A field expression; use the comma to separate multiple expressions if it is a merge by multiple fields, like x₁,x₂...

Return value:

An ordinary cursor

Example:

	A
1	=demo.query("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<6")	Data is ordered by EID
2	=demo.query("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<10 and EID>5")	Data is ordered by EID
3	=[A1.cursor(),A2.cursor()].mcursor()	Union A1 and A2 into a multicursor
4	=[A1.cursor(),A2.cursor()].mcursor()	Same as A3
5	=[A3,A4].mergex(EID)	Merge A3 and A3’s multicursors by EID
6	=A5.fetch()

mid()[917][918]

Description:

Return the substring of a string.

Syntax:

mid(s,start{,len})

Note:

The function returns a substring of s from the specified position start. The length of the substring is len.

Parameters:

s	The source string from which you get the substring
start	The starting position of the substring
len	The length of substring. By default, the length will be counted from the starting character to the end of the source string

Return value:

A string

Example:

mid("abcde",1)	abcde
mid("abcde",1,2)	ab
mid("abcde",3)	cde

Related functions:

left()

right()

millisecond()[919][920]

Description:

Get the millisecond from a specified datetime value.

Syntax:

millisecond(datetimeExp)

Note:

The function gets the millisecond from the datetime value datetimeExp.

Parameters:

datetimeExp

An expression whose result is a date or a datetime value of standard format

Return value:

An integer

Example:

millisecond(datetime("1980-02-27 12:00:02:123 ","yyyy-MM-dd HH:mm:ss:SSS"))		123
millisecond(now())	Milliseconds of the current time

Related functions:

year()

month()

day()

hour()

minute()

second()

min()[921][922]

Here’s how to use min() function.

A.min()[923][924]

Description:

Compute the minimum value of all the non-null members in a sequence.

Syntax:

A.min()

Equivalent to min(x₁,…,x_n)

Note:

The function computes the minimum value of all the non-null members in sequence A. Note that this function doesn’t apply to a sequence whose members are of different data types.

Parameters:

A	A sequence

Return value:

The minimum value of all members in sequence A

Example:

	A
1	=[8,-6,1,3,5].min()	-6
2	=["c","b","e","A"].min()	"A"
3	=["a",1].min()	An error message will be displayed because members are of different data types
4	=["a",null,"b"].min()	"a"
5	=min("c","b","e","A")	"A"

Related functions:

A.min(x)[925][926]

Description:

Compute x with each member of the sequence and then find the minimum value of the members of the new sequence

Syntax:

A.min(x)

Equivalent to A.(x).min()

Note:

The function loops through each member of sequence A to compute expression x and return the minimum value of members of the resulting sequence.

Parameters:

A	A sequence
x	Generally an expression of a single field name, or a legal expression composed of multiple field names.

Return value:

The minimum value of all members after computations have been performed on sequence A.

Example:

	A
1	*=demo.query("select from EMPLOYEE")**
2	=A1.min(SALARY)	Compute the lowest non-null value of SALARY
3	=A1.(SALARY+100).min()	Add 100 to the salary of each employee and then compute the lowest salary

Related functions:

A.min()

minp()[927][928]

Here’s how to use minp() function.

A.minp()[929][930]

Description:

Get the member that makes the minimum value for the expression.

Syntax:

A.minp(x)

Note:

The function computes expression x with each member of sequence A and returns the member which makes the minimum value for the expression x

Options:

@1	Return the first member that fulfills the condition.
@a	Return all the members that fulfill the condition. By default, return what @1 gets
@z	Search the member from back to front

Parameters:

A	A sequence
x	The expression to be computed

Return value:

The member which makes the minimum value for the expression x

Example:

	A
1	[2,5,4,3,2,1,4,1,3]
2	=A1.minp(~*~)	1, @1 is the default
3	=A1.minp@a(~*~)	[1,1]
4	=A1.minp@z(~*~)	1
5	=A1.minp@az(~*~)	[1,1]
6	=demo.query("select EID,NAME,BIRTHDAY from EMPLOYEE")
7	=A6.minp(BIRTHDAY)

Related functions:

A.pmin()

A.maxp()

minute()[931][932]

Description:

Get the minute from a datetime value.

Syntax:

minute(datetimeExp)

Note:

The function gets the minute from the specified datetime value datetimeExp.

Parameters:

datetimeExp

An expression whose result is a date or a datetime value of standard format

Return value:

An integer

Example:

minute(datetime("19800227","yyyyMMdd"))	0
minute("1972-11-08 10:20:30")	20
minute(datetime("2006-01-15 13:20:30"))	20

Related functions:

year()

month()

day()

hour()

second()

modify()[933][934]

Here’s how to use modify() function.

r.modify(xi:Fi,…)[935][936]

Description:

Modify the field values of a record.

Syntax:

r.modify(xi:Fi,…)

Note:

The function modifies the field values in record r, the status of r will be changed to 1(modify) after being modified. Automatically update the index, if any, and check distinctness.

Parameters:

r	The record to be modified
xi	Modification expression
Fi	Name of the field to be modified. The i^th field in r will be modified if Fi isn’t supplied.
r'	The new record that will replace record r

Options:

@r(r')	Replace record r with record r' according to the former’s order
@f(r')	Modify a certain field value of record r with record r'

Return value:

The modified record r

Example:

	A
1	=[[1,"Lucy",29]].new(~(1):ID,~(2):Name,~(3):Age)
2	=A1(1).modify(2,"Petter")	Modify the first and the second field
3	=A2.modify(30:Age)	Modify Age field
4	=A3.modify(3,33:Age)	Modify the first field and Age field
5	=[[4,"Lily",23]].new(~(1):SID,~(2):SName,~(3):SAge)
6	=A4.modify@r(A5(1))	Fill members of A5(1) in A4 according to A4’s order
7	=A6.modify@f(([["ella"]].new(~(1):Name))(1))	Modify only the value of Name field in A6

Related functions:

T.insert()

T.delete()

T.modify()[937][938]

Description:

Modify field values in a table sequence.

Syntax:

T.modify(k,xi:Fi,…)	Modify the k^th record, which is equal to T(k).modify(x_i:F_i,…)
T.modify(k:A,xi:Fi,…)	Modify the records from the k^threcord to the (k+\|A\|-1)^th record

Note:

The function modifies one or more records at the specified position(s). The status of the records which have been modified will be changed to 1. Automatically update the index, if any, and check distinctness.

Parameters:

k	The position at which the record will be modified. If k exceeds the limit, then append a new record in the end.
xi	The value of Fi field to be modified
Fi	Name of the field of the record which will be modified. If Fi is omitted, then modify the i^th field of T.
T	A table sequence
A	A sequence or an integer; If A is an integer, then it is equal to to(A)

Options:

@n	Return the newly-modified records or record sequences
@r(k:A)	Modify table sequence T using squence A from the k^th record according to the order of the fields
@f(k:A)	Modify table sequence T using squence A from the k^th record; only the common fields are modified.

Return value:

The modified table sequence T

Example:

	A
1	=demo.query("select * from DEPARTMENT")
2	=A1.modify(1,"Sales",5)
3	=A1.modify(2,6:MANAGER)
4	=A1.modify@n(2:1,"AAA":DEPT,76:MANAGER)	Return the modified second record
5	=create(DeptName,ManagerID)
6	=A5.modify(1:A1,DEPT:DeptName,MANAGER:ManagerID)
7	=A1.delete(A1.select(MANAGER>5))
8	=A5.modify@r(1:A7)	Modify A5 using A7 from the first record
9	=create(DeptName,MANAGER)
10	=A9.modify@f(1:A7)	Modify MANAGER field only

Related functions:

A.modify()[939][940]

Description:

Assign value(s) to one or more members of a sequence according to the specified position(s).

Syntax:

A.modify(k,x)	Assign x to the k^th member of sequence A
A.modify(k,X)	Assign members of X to members of A in order from the k^th position to the (k+\|X\|-1)^th position

Note:

The function assigns x to the k^th member of sequence A or members of X to the members of A from the k^th position to the number (k+|X|-1)^th position in order. Automatically update the index, if any, and check distinctness.

Parameters:

A	A sequence
k	A member position; If k is greater than the length of sequence A, then append the member in the end
x	A member value
X	A sequence

Options:

@n	Return the modified record or a record sequence of modified records

Return value:

A sequence

Example:

	A
1	=["a","c","d","e","f"]
2	=A1. modify(2,"g")	[a,g,d,e,f]
3	=A1.modify(6,[2,4,5])	[a,g,d,e,f,2,4,5]; append the values at the end as the specified position execeeds the limit
4	=demo.query("select * from STUDENTS")
5	=A4.modify@n(2:3,ID+10:ID)	Return a record sequence of modified records

Related functions:

A.delete()

A.insert()

mongo_close ()[941][942]

Description:
Close conncetion to MongoDB database.

Syntax:
mongo_close(fd)

Note:

The function closes conncetion to MongoDB database.

Parameters:

fd	MongoDB connection object

Example:

	A
1	=mongo_open("mongodb://localhost:27017/mydb")	Connect to a MongoDB
2	=mongo_close(A1)	Close the connection

mongo_insert()[943][944]

Description:

Insert data to a MongoDB database.

Syntax:

mongo_insert(fd,collection,T)

mongo_insert(fd,collection,cs)

Note:

The function inserts data of a table sequence or a cursor to a MongoDB database.

Parameters:

fd	A MongoDB database object to be connected
collection	A MongoDB collection
T	A table sequence
cs	A cursor

Return value:

Boolean value

Example:

	A
1	=mongo_open("mongodb://127.0.0.1:27017/mydb")	Connect to mydb database in Mongo server with IP: 127.0.0.1 and port 27017 and without a user name and a password
2	=demo.cursor("select NAME,GENDER,BIRTHDAY,DEPT,SALARY from employee where DEPT = 'R&D' ")	Query data in a table and return it as a cursor
3	=mongo_open("mongodb://127.0.0.1:27017/user0")	Query data in a table and return it as a table sequence
4	=mongo_insert(A1,"emp",A2)	Insert data in A2’s cursor to mongodb’s emp collection
5	=mongo_insert(A1,"emp",A3)	Insert data in A3’s table sequence to mongodb’s emp collection
6	=mongo_shell(A1,"emp.find()").fetch()	Get data from emp collection
7	=mongo_close(A1)	Close MongoDB connection

mongo_open()[945][946]

Description:
Connect to the MongoDB server.

Syntax:
mongo_open(url)

Note:

The function establishes a connection to the MongoDB server. If parameter username is absent, parameter password can be omitted.

Parameters:

url	mongodb://[username:password@]host1[:port1] [,host2[:port2],...[,hostN[:portN]]]/database[?options]
username：password	Username and password; can be omited
host	The host name or IP of to-be-connected MongoDB server; at least one value needs to be specified; to connect a replica set, specifiy multiple host machine IPs
port	Port number
database	Database name
options	MongoDB connection in standard format; can bet omitted

Return value:
MongoDB connection object

Example:

	A
1	=mongo_open("mongodb://root:sa@localhost:27017/col")	With username root, password sa, host name localhost, and port number 27017, connect to database col on MongoDB server
2	=mongo_open("mongodb://127.0.0.1:27017/mydb")	With IP: 127.0.0.1 and port number 27017, connect to database mydb on MongoDB server; no username and password
3	=mongo_open("mongodb://127.0.0.1/mydb?safe=true; wtimeoutMS=2000")	Conncet to database mydb on MongoDB server via IP: 127.0.0.1 in the safe mode; no port number; timeout value is 2 seconds

mongo_shell()[947][948]

Description:
Query the databsase and return the query result.

Syntax:
mongo_shell(fd,s)

Note:

The function executes aMongoDB shell command s and returns the result. So far functions supported by s are find, count, distinct and aggregate.
Options:

@x	Close the MongoDB connection automatically closes when the execution finishes; if the returned result is a cursor, disconnect from the database as the cursor closes.

Parameters:

fd	MongoDB connection object
s	An MongoDB function, which supports find, count, distinct and aggregate and follows the MongoDB syntax

Return value:
A sequence/table sequence/cursor

Example:

	A
1	=mongo_open("mongodb://localhost:27017/mydb")	Conncet to database mydb on MongoDB server
2	=mongo_shell(A1,"emp.find()").fetch()	Query records of the emp set in database mydb
3	=mongo_shell(A1,"emp.find({GENDER:\"F\"})")	Query records where GENDER is F and return result as a cursor
4	=A3.fetch()
5	=mongo_shell@x(A1,"emp.count()")	Use @x option to query the number of records, and close the connection after result is returned
6	=mongo_open("mongodb://localhost:27017/mydb")	Connect to the MongoDB database
7	=mongo_shell(A6,"emp.aggregate([{$group : {_id : \"$GENDER\", number : {$sum : 1}}}])")	Count records by gender
8	=mongo_shell(A6,"emp.distinct(DEPT)")	Query DEPT in the emp set to remove duplicate values
9	=mongo_close(A6)	Close the database connection

month()[949][950]

Description:

Get the month from a specified date/datetime value.

Syntax:

month(dateExp)

Note:

The function gets the month from the date dateExp.

Parameters:

dateExp

An expression whose result is a date or a datetime value of standard format.

Options:

@y	Return a 6-digit number if there is a year part in the parameter

Return value:

An integer

Example:

month(datetime("19800227","yyyyMMdd"))	2
month("1972-11-08 10:20:30")	11
month(datetime("2006-01-15 13:20:30"))	1
month@y("1972-11-08 10:20:30")	197211

Related functions:

year()

day()

hour()

minute()

second()

movefile()[951][952]

Here’s how to use movefile() function.

movefile(fn,path)[953][954]

Description:

Move, delete, or rename a file.

Syntax:

movefile(fn,path)

Note:

The function moves file fn to a file specified by parameter path. Delete file fn if path is absent; rename the file if only the file name is specified in the path.

Parameters:

fn	A file
path	The path (with file name) along which the file is moved, or a file name

Options:

@y	Force an execution of the function if the target file already exists. Without the option you can’t force an execution. Delete the target file if parameter path is absent.
@c	Copy the file. If the target file name is the same as that of the specified file to which it will be moved, the copy fails.

Return value:

Boolean value

Example:

	A
1	=movefile(file("E://test.property"),"D://testfile.property")	Move the file to testfile.property file under root directory on driver D
2	=movefile(file("D://testfile.property"),"file.property")	D://testfile.property is renamed file.property
3	=movefile(file("D://file.property"))	Delete file.property
4	=movefile@y(file("E://test1.property"),"D://testfile1.property")	The file testfile1.property already exists. Force the move and override the original file
5	=movefile@c(file("D://testfile1.property"),"file.property")	Copy the file, instead of renaming it
6	=movefile@cy(file("E://test2.property"),"D:// file.property")	file.property already exists. Force the copy and override the original file
7	=movefile@y(file("D://testfile1.property"))	Delete testfile1.property

Related functions:

f. exists()

f. date()

n.f(x)[955][956]

Description:

Perform a loop operation by declaring an integer loop variable.

Note:

The function performs a loop operation with integer n as the loop variable.

n.(x)	Equivalent to to(n).(x)
n.f(x)	Equivalent to to(n),f(x)

Parameters:

n	An integer
x	An expression
f	The function name

Example:

Ø n.(x)

	A
1	=3.(~*2)	[2,4,6]

Ø n.f(x)

	A
1	=3.sum(~*2)	12

name()[957][958]

Here’s how to use name() function.

f.name()[959][960]

Description:

Return a file’s path relative to the main directory.

Syntax:

f.name()

Note:

The function returns file f’s path relative to the main directory; return the full path if f isn’t in the main directory.

Parameters:

A file

Options:

@p Return a full path

Return value:

String

Example:

	A
1	=file("G:/Program files/raqsoft/esProc/demo/data/data.txt").name()	Return the path which is relative to the main directory because the file is under the main directory: G:/Program files/raqsoft/esProc/demo
2	=file("E:/Program files/raqsoft/esProc/data/data.txt").name()	Return the full path when the file isn’t in the main directory
3	=file("employee1.txt").name@p()	Return the full path since employee1.txt is in the main directory

new()[961][962]

Here’s how to use new() function.

A.new(xi_:Fi,…)[963][964]

Description:

Generate a new table sequence/record sequence, whose field values are computed from the field values of a table sequence/record sequence.

Syntax:

A.new(xi:Fi,…)

Note:

The function generates a new table sequence/record sequence with the same length as table sequence/record sequence A, the field names and values of which are respectively Fi and xi. When parameter xi is #i, it represents the i^th field and the original field name will be used.

Parameters:

Fi	Field name. If omitting it, then use the identifier parsed from the xi.
xi	Expression whose result is the field value. If omitted, field values will be null and :Fi must not be omitted at the same time. The sign # is used to represent a field with a sequence number.
A	Table sequence/record sequence.

Options:

@m	Use parallel algorithm to handle data-intensive or computation-intensive tasks; no definite order for the records in the result set.
@i	Won’t generate a record if the result of expression xi is null.

Return value:

The new table sequence.

Example:

Ø Generate from an individual table sequence

	A
1	=demo.query("select EID,NAME,DEPT,BIRTHDAY from EMPLOYEE")
2	=A1.new(EID:EmployeeID,NAME, #3:dept)
3	=A1.new(NAME,age(BIRTHDAY):AGE)	Generate the new table sequence by computing new field values.
4	=A1.new@m(NAME,age(BIRTHDAY):AGE)	Use @m option to increase performance of big data handling.
5	=file("D:\\txt_files\\data1.txt").import@t()	Below is the file data1.txt:
6	=A5.new@i(CLASS,STUDENTID,SUBJECT,SCORE:score)	If the SCORE value is null, the corresponding record won’t be generated

Ø Generate from multiple table sequences of the same order

	A
1	=create(Name,Chinese).record(["Jack",99,"Lucy",90])
2	=create(Name,Math).record(["Jack",89,"Lucy",96])
3	=A1.new(Name:Name,Chinese:Chinese,A2(#).Math:Math)

Related functions:

cs.new()

ch.new()[965][966]

Description:

Return the channel with newly-computed field values for its records.

Syntax:

ch.new(x_i:F_i,…)

Note:

The function computes expression x_iover each of the records in channel ch, names the new fields F_i, and returns the original ch consisting of F_ifields. This is an attached computation.

Parameters:

ch	Channel
x_i	An expression, whose values are used as new field values. It is treated as null if omitted; in that case, parameter : F_i can’t be omitted. The sign # is used to represent a field with a sequence number
F_i	Field name in the given channel; use the identifiers parsed from expression x_iif it is omitted

Options:

@i	Won’t generate the corresponding record when the result of computing expression x_iis null

Return value:

The original channel with new field values

Example:

	A
1	*=demo.cursor("select from SCORES")**	Create a cursor
2	=file("D:\\txt_files\\data1.txt").import@t()	Below is data1.txt:
3	=channel()	Create a channel
4	=channel()	Create a channel
5	=A3.new(CLASS,#2:ID,SCORE+5:newScores)	Change the structure of A2’s channel into CLASS, ID and newScores, among which the newScores values are computed from the original SCORE values according to an expression
6	=A3.fetch()	Fetch and store the existing data in the channel
7	=A4.new@i(CLASS,STUDENTID,SUBJECT,SCORE:score)	Won’t generate the corresponding record if the result of computing a SCORE value is null
8	=A4.fetch()
9	=A1.push(A3)	Be ready to push data in A1’s cursor into A3’s channel, but the action needs to wait
10	=A2.push(A4)	Push data in A2’s sequence into A4’s channel
11	=A1.fetch()	Data in A1’s cursor is pushed into the channel and operations are performed as the fetch() operation is performed over A1
12	=A3.result()
13	=A4.result()

cs.new()[967][968]

Description:

Return a cursor with newly-computed field values for its records.

Syntax:

cs.new(xi:Fi,…)

Note:

The function computes expression xi against each record in cursor cs, names the newly-computed Fi fields, and returns the original cursor containing Fi fields.

Parameters:

cs	Cursor
x_i	An expression, whose values are uses as the new field values. It is treated as null if omitted; in that case, : F_i can’t be omitted. The sign # is used to represent a field with a sequence number
F_i	Field name of cs; use the identifiers parsed from expression x_iif it is omitted

Options:

@i	Won’t generate a record if the result of expression xi is null

Return value:

The original cursor with new field values

Example:

	A
1	=connect("demo").cursor("select * from SCORES where SCORES<60")
2	=A1.new(#2:ID, CLASS, SCORE+5:newScores)	Generate a new cursor composed of ID, CLASS, and newScores by performing expression evaluation on the existing SCORE field
3	=A2.fetch()
4	=file("D:\\txt_files\\1.txt").cursor@t()	Below is the file data1.txt:
5	=A4.new@i(CLASS,STUDENTID,SUBJECT,SCORE:score)	If the SCORE value is null, the corresponding record won’t be generated
6	=A5.fetch()

T.new(A/cs,x:C,…;wi,...)^{^[969]}^{^[970]}

Description:

Retrieve non-key fields from a composite table according to key values of a table sequence/record sequence or a cursor and return a table sequence or a cursor.

Syntax:

T.new(A/cs,x:C,…;wi,…)

Note:

The function retrieves non-key fields from composite table T according to key values of table sequence/record sequence A or cursor cs; parameter A/cs is ordered by their key.

Parameters:

T	A composite table
A/cs	A table sequence/cursor
x	Field values
C	Column alias
wi	Filtering condition; separate multiple conditions, which should be met at the same time, by comma(s)

Return value:

A table sequence/cursor

Example:

	A
1	=file("D:\\emp10.ctx")
2	=A1.create()	Open a composite table
3	=demo.query("select EID from EMPLOYEE")
4	=A2.new(A3,NAME,GENDER)	Retrieve non-key fields from A2’s composite table accroding to the key values of A3’s table sequence
5	=demo.query("select EID from EMPLOYEE").cursor()
6	=A2.new(A5,NAME:NAME,GENDER:GENDER).fetch()	Retrieve non-key fields from A2’s composite table accroding to the key values of A5’s cursor
7	=file("D:/employees.ctx").create()	Open a composite table
8	=demo.query("select EID from employee where EID<10 ").keys(EID)	Return a table sequence
9	=A7.new(A8,EID,Gender,Dept;Gender=="F",Dept=="Sales")	Retrieve Gender field and Dept field from A7’s composite table by the key EID; filtering condition is Gender=="F" & Dept=="Sales"

T.new(A/cs,x:C,…;wi,...)^{^[971]}^{^[972]}

Description:

Retrieve non-key fields from a cluster composite table according to key values of a table sequence/record sequence or a cursor and return a table sequence or a cluster multcursor.

Syntax:

T.new(A/cs,x:C,…;wi,…)

Note:

The function retrieves non-key fields from cluster composite table T according to key values of table sequence/record sequence A or cursor cs; parameter A/cs is ordered by their key.

Parameters:

T	A composite table
A/cs	A table sequence/cursor
x	Field values
C	Column alias
wi	Filtering condition; separate multiple conditions, which should be met at the same time, by comma(s)

Return value:

A table sequence/cursor

Example:

	A
1	=file@0("emp10.ctx",["192.168.0.118:8281"])
2	=A1.create()	Open a composite table
3	=demo.query("select EID from EMPLOYEE")
4	=A2.new(A3,NAME,GENDER)	Retrieve non-key fields from A2’s cluster composite table accroding to the key values of A3’s table sequence
5	=demo.query("select EID from EMPLOYEE").cursor()
6	=A2.new(A5,NAME:NAME,GENDER:GENDER).fetch()	Retrieve non-key fields from A2’s cluster composite table accroding to the key values of A5’s cursor

news()[973][974]

Here’s how to use news() function.

A.news(X;xi:Fi,…)[975][976]

Description:

Compute field values based on a table sequence/record sequence, and concatenate them to generate a new one.

Syntax:

A.news(X;x_i:F_i,…)

Note:

The function computes field values based on record sequence X, concatenates the newly-computed fields to create a new table sequence/record sequence where parameter x_iis field value of each record and F_iis the field name, which will be automatically identified according to parameter x_i if F_i is omitted. When parameter xi is #i, it represents the i^th field and the original field name will be used.

Parameters:

A	A table sequence/record sequence
X	A record sequence/integer; equivalent to to(X) if it is an integer, meaning the frequency of inserting each record in A
x_i	Expression, whose results will be field values; the sign ~ used in the parameter references data from record sequence X instead of A. The sign # is used to represent a field with a sequence number
F_i	Field name of the new table sequence/record sequence; when omitted, it will be automatically identified

Return value:

A new table sequence/record sequecne

Example:

	A
1	*=demo.query("select from EMPLOYEE")**
2	=A1.group(GENDER;~:group,~.avg(SALARY):avg)	Perform group by GENDER
3	=A2.news(group;EID,NAME,GENDER, #3:surname, age(~.BIRTHDAY):age,SALARY+50: salary,A2.avg:AvgSalary)	A2 is composed of data groups; based on each group field values are computed and a table sequence is generated; and then table sequences are concatenated into a new one.
4	=A1.news(2;EID,NAME,GENDER,STATE,age(A1.BIRTHDAY):AGE)	Generate a new table sequence by inserting each record twice
5	=A1.group(DEPT).(~.group(GENDER))	Group records first by DEPT then by GENDER
6	=A5.news(~;A5.~.DEPT:DEPT,A5.~.~.GENDER:GENDER,A5.~.~.avg(SALARY):AvgSalary)	Get DEPT values and GENDER values from A5 to show the average salaries of different GENDERs in every DEPT

Related functions:

cs.new()

ch.news()[977][978]

Description:

Get new values for the fields of records in a channel and update them into the channel.

Syntax:

ch.news(X;x_i:F_i,…)

Note:

With channel ch, the function computes values of fields in record sequence X and updates the new field values into the channel. F_iis the new field name that will be automatically identified if the parameter is omitted; x_i represents the new field values. This is an attached computation.

Parameters:

ch	Channel
X	Record sequence
x_i	Expression, whose results will be field values; the sign ~ used in the parameter references data from X instead of A. The sign # is used to represent a field with a sequence number
F_i	Field name in the given channel; will be automatically identified if the parameter is omitted

Return value:

The original channel with new fields

Example:

	A
1	*=demo.cursor("select from EMPLOYEE")**
2	*=demo.query("select from EMPLOYEE")**
3	=channel()	Create a channel
4	=A2.group(GENDER;~:group)	Group records by GENDER
5	=A1.groupx(GENDER;avg(SALARY):avg)	Group records by GENDER
6	=A5.join(GENDER,A4:GENDER,group)
7	=A3.news(group;EID,NAME,GENDER,#3:surname, age(~.BIRTHDAY):age,SALARY+50: salary,avg:AvgSalary)	A6 is one of the groups; compute field values based on each group and concatenate the results into A3’s channel
8	=A3.fetch()	Fetch and store the existing data in the channel
9	=A6.push(A3)	Be ready to push data in A6’s cursor into A3’s channel, but the action needs to wait
10	=A6.fetch()	Data in A6’s cursor is pushed into the channel and operations are performed as the fetch() operation is performed over A6
11	=A3.result()

cs.news()[979][980]

Description:

Compute new cursor field values to update them into the original cursor.

Syntax:

cs.news(X;x_i:F_i,…)

Note:

The function computes field values based on cursor cs, updates the newly-computed fields into the original cursor where x_iis field value of each record and F_iis the new field name, which will be automatically identified if F_i is omitted.

Parameters:

cs	Cursor
X	Record sequence
x_i	An expression, whose values are uses as the new field values. It is treated as null if omitted; in that case, : F_i can’t be omitted. The sign # is used to represent a field with a sequence number
F_i	Filed name of the new cs; use the identifiers parsed from expression x_iif it is omitted

Return value:

The original cursor with the new field values

Example:

	A
1	*=demo.cursor("select from EMPLOYEE")**
2	*=demo.query("select from EMPLOYEE")**
3	=A2.group(GENDER;~:group)	Perform group by GENDER
4	=A1.groupx(GENDER;avg(SALARY):avg)	Perform group by GENDER
5	=A4.join(GENDER,A3:GENDER,group)
6	=A5.news(group;EID,NAME,GENDER,#3:surname, age(~.BIRTHDAY):age,SALARY+50: salary,avg:AvgSalary)	A4 is composed of data groups; based on each group field values are computed and a cursor is generated; and then cursors are concatenated into a new one.
7	=A6.fetch()

Related functions:

A.news(X;x_i:F_i,…)

T.news(A/cs,x:C,…;wi,...)[981][982]

Description:

Retrieve fields from a table sequence or a cursor according to key values to form a new table sequence.

Syntax:

T.news(A/cs,x:C,…;wi,...)

Note:

The function retrieves fields from table sequence A or cursor cs according to key values to form a new table sequence. It can perform a one-to-many association between a table sequence/cursor and a composite table and return a result set consisting of composite table T’s records pointing to the table sequence/cursor.

Parameters:

T	A composite table
A/cs	A table sequence/cursor/composite table cursor
x	Field value
C	Column alias
wi	Filtering condition; multiple conditions are separated by comma(s) and they must be met at the same time

Return value:

A table sequence

Example:

	A
1	=file("score.ctx").create()	Open a composite table file
2	=demo.query("select * from students").keys(ID)	Return a table sequence with ID as the key
3	=A1.news(A2,STUDENTID,SUBJECT,SCORE;SUBJECT=="Math",SCORE>70)	Join A1’s composite table and A2’s table sequence where the filteing condition is SUBJECT=Math & SCORE>70 and return eligible records in the composite table

next{a}[983][984]

Description:

Skip the current loop and continue with the next loop.

Syntax:

next{a}

Note:

next is used to skip the remaining code block in the current loop and execute the next loop as long as the cycling does not finish.

Parameters:

a	The master cell of the loop code block. If the master cell a is omitted, then it is the current loop that is running.

Example:

	A	B	C	D
1	=[]				[1,1,3,3]
2	for 5				In this example, the next A2 and the break A2 are to control loop of the A2 level. The computation of A1 is the sequence [1, 1, 3, 3]
3		for 2
4			if A2==2	next A2
5			if A2==4	break A2
6			>A1=A1\|[A2]
7	=demo.query("select * from EMPLOYEE")
8	=create(ID,Dept)
9	for A7				Extract records whose DEPT values are not "Sales" from the EMPLOYEE table
10		if A9. DEPT=="Sales"
11			Next
12		>A8.insert(0,A9.EID: ID,A9. DEPT:Dept)			A8 returns the result

Note:

1. By comparison, the break is to jump out of the cycling directly, while next is to ignore the remaining code block in the current loop, and proceeds to the next loop as long as the cycling does not finish.

2. If a is omitted, then the current loop will be under control. To control the loop at higher level, a is required.

nodes()[985][986]

Here’s how to use nodes() function.

P.nodes()[987][988]

Description:

Find the children nodes of a specified record.

Syntax:

P.nodes(F,r,n)

Note:

The functions performs recursive query on field F of record sequence P referred by the foreign key until the value of field F is equal to r, and returns the children nodes of the record r. If the specified record r can’t be found, the function will return NULL. n is the maximum recursion depth, its default value is 1,000.

Parameters:

P	A record sequence
F	Field name
r	A record
n	A number

Options:

@d	Make the function return leaf-level nodes
@p	Make the function return paths connecting children nodes and their leaf-level nodes

Return value:

A sequence

Example:

	A
1	=file("D://emp.txt").import@t().keys(empid)
2	>A1.switch(mgrid,A1:empid)
3	=A1.nodes(mgrid,A1.select@1(name=="Diana"),5)	According to mgrid field, the foreign key references, search for all records of Diana’s subordinates and those of the subordinates of Diana’s subordinates
4	=A1.nodes@d(mgrid,A1.select@1(name=="Diana"),5)	Search for the records of Diana’s subordinates who are not an executive
5	=A1.nodes@p(mgrid,A1.select@1(name=="Diana"),5)	Display a relationship structure with Diana as the root, from which you see that Diana is the superior of empid=7, who is the superior of empid=14

not()[989][990]

Description:

On integers, perform bitwise NOT operation to get the logical negation on each bit.

Syntax:

not(x)

Note:

The function performs bitwise NOT operation to get the logical negation on each bit of an integer.

Parameters:

x	The numeric expression for which you want to find the logical negation on each bit

Return value:

An integer

Example:

not(6)

-7

now()[991][992]

Description:

Get the current system datetime.

Syntax:

now()

Note:

The function gets the current system datetime accurate to the millisecond.

Options:

@d	Return the date part only, date type
@t	Return the time part only, time type
@m	Acurrate to minute
@s	Accurate to second

Return value:

Datetime

Example:

now()	The current system datetime, for example: 2010-07-15 16:10:40
now@d()	The current system date, for example:2010-07-15
now@t()	The current system time, for example:16: 10: 40
now@m()	The current system datetime, for example:2013-12-09 17:05:00:0
now@s()	Current system datetime, for example:2013-12-09 17:05:33:0

null[993][994]

Description:

Null value

Syntax:

null	Usually the value of an empty cell is null.

Note:

It can be used directly in a constant cell or expression.

Example:

	A	B
1	=null		Assign a null value to A1
2	=A1==null		Judge if A1 is null
3	if A2==true	>a=4	If it is null, assign 4 to a
4	else	>a=3	Otherwise, assign 3 to a

Related functions:

true

false

number()[995][996]

Description:

Convert a string to a number.

Syntax:

number (stringExp,format)

Note:

The function parses string stringExp as a numeric value in the format of fmt.The value of stringExp must be a numeric string.

Parameters:

stringExp	A string expression, the result of which is a numeric value
format	A format string;can be absent

Return value:

32-bit integer, 64-bit integer, or 64-bit floating-point number

Example:

number("123")	123
number("123f")	123.0
number("123.45")	123.45
number("123.456d")	123.456
number("$1,100.05","$#,###.##")	1100.05

Related functions:

float()

int()

long()

decimal()

string()

nvl()^{^[997]}^{^[998]}

Description:

Get the first non-null member that isn’t double quoted from an integer sequence.

Syntax:

A.nvl()

Equivalent to nvl(x₁,…,x_n)

Note:

The function gets the first non-null member that isn’t double quoted from integer sequence A.

Parameters:

A	An integer sequence

Return value:

A non-null an non-double-quoted member

Example:

	A
1	=[1,2,4].nvl()	1
2	=[null,2,3,4].nvl()	2
3	=["",2,3,4].nvl()	2

olap_close()[999][1000]

Description:

Close connection to a multidimensional database.

Syntax:

olap_close(conn)

Note:

This external library function closes the connection to a multidimensional database.

Parameters:

conn

Database connection string

Example:

	A
1	=olap_open("http://192.168.0.178:8088/msmdpump.dll","CubeTest","Administrator","admin")
2	>olap_close(A1)	Close connection to the multidimensional database

Related functions:

olap_open()

olap_query()

olap_open()[1001][1002]

Description:

Establish connection to multidimensional database.

Syntax:

olap_open(url, catalog, user, pwd)

Note:

An external library function. Whether or not the username and password are required depends on how the privilege levels are set up for the given server.

Parameters:

url	Address of the server on which a multidimensional database runs
catalog	The multidimensional database name
user	User name for accessing a multidimensional database
pwd	Password for accessing a multidimensional database

Return value:

Return the connection object

Example:

	A
1	=olap_open("http://192.168.0.178:8088/msmdpump.dll","CubeTest","Administrator","admin")	Connect to the multidimensional database named CubeTest
2	=olap_open("http://192.168.0.178:8088/msmdpump.dll","Analysis Services Tutorial")	Connect to the multidimensional database named Analysis Services Tutorial

Related functions:

olap_close()

olap_query()

olap_query()[1003][1004]

Description:

Query data in a multidimensional database and return the result.

Syntax:

olap_query(conn,mdx)

Note:

This external library function queries data from a multidimensional database and returns the result.

Options:

@c	Return a cursor

Parameters:

conn	The connection object
mdx	A multidimensional database query that allows one or two axes

Return value:

A table sequence or a cursor

Example:

	A
1	=olap_open("http://192.168.0.178:8088/msmdpump.dll","CubeTest","Administrator","admin")	Connect to the multidimensional database named CubeTest
2	=olap_query(A1," select {[Measures].[OrderAmount]} on columns from [DataSourceMulti]")	Find out total sales amount
3	=olap_query@c(A1," with member [Measures].[AnnualInterestRate] as '[Measures].[SalesAmount]/[Measures].[StandardCost]-1' select{[Measures].[SalesAmount],[Measures].[StandardCost],[Measures].[ AnnualInterestRate]} on columns, {[Order Date].[Calendar Year].[Calendar Year]} on rows from [DataSourceMulti]")	Find out each year’s sales amount and standard cost and calculate the annual interest rate, and return result as a cursor
4	=A4.fetch(5)
5	>olap_close(A1)	Close connection to the dimensional database

Related functions:

olap_close()

olap_open ()

or()[1005][1006]

Description:

Perform bitwise OR operation on integers.

Syntax:

or(x_i,…)

or(A)

Note:

Bitwise OR operation on integers.

Parameters:

A	A sequence
x_i	A numeric expression based on which you perform the bitwise OR operation

Retrun value:

An integer

Example:

or(3,5)

output()[1007][1008]

Description:

Output data to console.

Syntax:

output(x,...)

Note:

The function exports one or more variables separated with the comma; the data printed out from console is separated with the tab. If parameter x is a table sequence, the function can only export 10 rows at most; to export all rows, use A.export() function first to convert the table sequence into strings and then output the data with this function.

Parameters:

x,…	Export parameters separated with the comma.

Options:

@t	Output data as well as the current time which will be placed before the printout data.

Example:

	A
1	=to(4)
2	=output(A1)	Output “[1,2,3,4]”
3	=output@t(A1)	Output “2013-05-02 11:51:59 [1,2,3,4]”
4	=demo.query("select * from employee").export()
5	=output(A4)	Output all rows in the table sequence

p()[1009][1010]

Here’s how to use p() function.

A.p()[1011][1012]

Description:

Get sequence numbers of the members at specified positions.

Syntax:

A.p(i)	-n<=i<=n; 1<=i<=n indicates getting the sequence number of the i^th member; -n<=i<=-1 indicates getting the sequence number of the i^thmember backwards.
A.p(P)	P is the n-integer sequence whose length is m. Its members should be greater than -n and less than n, but they should not be equal to 0.

Note:

A is a sequence whose length is n, from which you get sequence numbers of the members at specified positions. The function is generally used to get the sequence numbers of the members reversely.

Parameters:

A	A sequence object whose length is n
i	An integer
P	An n-integer sequence whose length is m

Options:

@r	Turn back if the specified position exceeds the boundary of A, that is, to set i=if(i%n==0,n,i%n), where n is the length of A.
@0	The member represented by a sequence number that exceeds the boundary of A will be excluded from the result of A.p(P).

Return value:

An integer or an integer sequence composed of sequence numbers of members at specified positions in a sequence

Example:

	A
1	[a,b,c,d,e,f,g,h,i,j]
2	=A1.p(2)	2
3	=A1.p(-2)	9
4	=A1.p([2,3])	[2,3]
5	=A1.p([-2,-3])	[9,8]
6	=A1.p@0([5,12])	[5]
7	=A1.p@r([5,12])	[5,2]

Related functions:

A.m()

pad()[1013][1014]

Here’s how to use pad() function.

pad()[1015][1016]

Description:

Pad a string to the specified length with another string added on the left.

Syntax:

pad(s,c,l)

Note:

The function pads string s to a new length of l by continuously adding characters of string c to the left side.

Parameters:

s	A string expression
c	A string expression
l	A number or an xpression whose result is the numeric value

Options:

@r	Pad to the right side of a string, to a new length

Return value:

String

Example:

	A
1	=pad("Soth","Miss",10)	The return value is" MissMiSoth "
2	=pad@r("Soth","er",8)	The return value is" Sotherer "

A.pad()[1017][1018]

Description:

Add members of a sequence to another one until the latter reaches certain length.

Syntax:

A.pad(x,n)

Note:

The function adds members of sequence x sequentially and continuously to sequence A until the length of A reaches n. If n is less than A’s length, the function will return A itself.

Parameters:

A	A sequence
x	A single value or a sequence; with a sequence, add its members sequentially to sequence A
n	An integer

Options:

@l	Add members before the existing members of sequence A; by default the additions will be placed at its end.
@m	If the length of sequence A is the multiple of n, do not perform the adding action. If the length of A isn’t the multiple of n, add members to A until its length is the multiple of n; the number of additions – which are members of sequence x – need to be added after the existing members can be calculated with the formula – m=n-A.len()%n.

Return value:

Sequence

Example:

	A
1	[a,b,c,d,e,f]
2	=A1.pad(["q",2],2)	["a","b","c","d","e", "f"]
3	=A1.pad("j",9)	["a","b","c","d","e", "f","j","j","j"]
4	=A1.pad@m("j",7)	["a","b","c","d","e", "f","j"]
5	=A1.pad@m("j",3)	["a","b","c","d","e", "f"]
6	=A1.pad@l(["q",2],11)	["q",2, "q",2, "q","a","b","c","d","e", "f"]

parse()[1019][1020]

Description:

Parse a string into the corresponding data type.

Syntax:

parse(s)

Note:

This function analyzes string s and parses it into corresponding data type.

Parameters:

String

Options:

@e	Remove quotes of the string before starting an escape sequence including the escape character and unicode. By default the string will not be escaped.
@n	Retrieve a substring with enough length starting from the left side and parse it, while ignoring the non-numeric rest. Note that the string needs to begin with the numeric value.
@q	If a string starts with the squotation marks, parse it until the next quotation marks appear and leave the rest of the string alone, and return a string.

Return value:

Data of different data types

Example:

	A
1	="10:20:30"
2	=parse(A1)	10:20:30. The string is parsed into time data type
3	\u4e2d\u56fd
4	a\tb
5	=parse@e(A3)	中国. The string is automatically parsed into the corresponding Unicode characters
6	=parse@e(A4)	a b. Escape characters are handled automatically
7	=parse@n("12sadsdxc23")	12. Retrieve and parse the first numeric value
8	=parse@q("\'sadsdxc\'+23")	'sadsdxc' ; the string begins with quotation marks and the parsing stops at the next quotation marks

paste()[1021][1022]

Here’s how to use paste() function.

T.paste()[1023][1024]

Description:

Loop through the records of a sequence to modify the specified field of a table sequence in order.

Syntax:

T.paste(A_i:F_i,…;k)

Note:

The function loops through the records of sequence A_ito modify the values of F_ifield of table sequence T from the k^th record. The modification will stop once the the number of records that have been modified reaches this result number.

Parameters:

T	A table sequence
A_i	A table sequence/record sequence/sequence, whose records/members will be values of F_ifield
F_i	The field to be modified; when it isn’t supplied, modify the i^th field of T
k	The position the modification starts. The default is 0, in which case records or members will be appended at the end.

Options:

@i	Loop through the records of sequence A_ito insert them to F_ifield of table sequence T before the k^th record.

Return value:

A table sequence

Example:

	A
1	*=demo.query("select from DEPARTMENT").keys(DEPT)**
2	=A1.modify(1,"Sales",5)
3	*=demo.query("select from DEPARTMENT")**
4	=A3.paste(A1:DEPT,[20,10,20]:MANAGER;3)	Modify values of records according to different fields
5	=A3.paste@i(A1:DEPT,[20,10,20]:MANAGER;3)	Insert values according to different fields.

pdate()[1025][1026]

Description:

Get the first day and the last day of the week/month/quarter to which a date belongs.

Syntax:

pdate (dateExp)

Note:

The function gets the first day and the last day of the week/month/quarter to which the date dateExp belongs.

Parameters:

dateExp Expression whose result is a date, or of standard date format

Options:

@w	Get the Sunday of the week to which the specified date belongs
@we	Get the Saturday of the week to which the specified date belongs
@m	Get the first day of the month to which the specified date belongs
@me	Get the last day of the month to which the specified date belongs
@q	Get the first day of the quarter to which the specified date belongs
@qe	Get the last day of the quarter to which the specified date belongs The default is to get the Sunday of the week to which the specified date belongs
@y	Get the first day of the year to which the specified data belongs

Return value:

Datetime type

Example:

pdate@w(datetime("19800227","yyyyMMdd"))	1980-02-24
pdate@we (datetime("19800227","yyyyMMdd"))	1980-03-01
pdate@m(datetime("19800227","yyyyMMdd"))	1980-02-01
pdate@me(datetime("19800227","yyyyMMdd"))	1980-02-29
pdate@q(datetime("19800227","yyyyMMdd"))	1980-01-01
pdate@qe(datetime ("19800227","yyyyMMdd"))	1980-03-31
pdate@y(datetime("19800227","yyyyMMdd"))	1980-01-01

penum()[1027][1028]

Here’s how to use penum() function.

E.penum()[1029][1030]

Description:

Judge to which enum group an object belongs.

Syntax:

E.penum(y)

Note:

The functions judges to which group of record sequence E the y belongs, and returns the sequence number(s) of the group(s), i.e. sequence number(s) of the record(s) of E that satisfy the grouping condition.

Parameters:

E	A sequence/record sequence
y	y is allowed to be omitted

Options:

@r	Return the sequence numbers of all the groups satisfying the grouping condition, and the default is to return the sequence number of the first group
@n	If no eligible sequence member of E is found, return the length of E plus 1.

Function keyword:

?	Represents the value of y

Return value:

A sequence number or an integer sequence composed of sequence numbers

Example:

Ø E is the sequence

	A
1	=["?<=70&&?<=60","?>=70 && ?<=90","?>=90"]	Use y to replace the ? in the grouping conditions when computing
2	=A1.penum(90)	2; the sequence number of the first group satisfying the condition will be returned
3	=A1.penum@r(90)	[2,3]; return the sequence numbers of all the groups
4	=A1.penum@n(43)	4

Related functions:

P.enum()

periods()[1031][1032]

Description:

Generate a sequence of datetime values by specified regular intervals.

Syntax:

periods(s,e,i)

Note:

The function generates a new sequence composed of datetimes in a period from s to e inclusive at a regular interval of i.

Parameters:

s	A datetime variable
e	A datetime variable
i	An integer indicating the interval; its unit is day and its value is 1 by default

Options:

@y	i is the year
@q	i is the quarter
@m	i is the month
@t	i is measured by ten days
@s	i is the second
@x	Exclusive of the ending point
@o	Do not adjust the first datetime value to the beginning point of the time unit. By default, it will be adjusted, and the adjustment is mandatory in the case of using @t.

Return value:

A new sequence composed of datetimes

Example:

	A
1	2000-08-10 12:00:00
2	=periods@y(A1,now(),1)	Set year as the interval unit
3	=periods@yo(A1,now(),1)	Do not adjust the first datetime; it is adjusted to the beginning point of the time unit by default, and must be adjusted when using @t.
4	=periods@q(A1,now(),1)	Set quarter as the interval unit
5	=periods@m(A1,now(),1)	Set month as the interval unit
6	=periods@s(A1,now(),7)	Set second as the interval unit
7	=now()
8	=pdate@m(A7)	Get the beggining date of the current month
9	=pdate@me(A7)	Get the ending date of the current month
10	=elapse(A8,6-day@w(A8))	Get the first Friday
11	=periods@x(A10,A9,7)	Get the sequence of Fridays
12	=A11(2)	Get the second Friday
13	=A11.m(-1)	Get the last Friday
14	=A11.len()	Get the number of Fridays

permut()[1033][1034]

Description:

Return the number of permutations.

Syntax:

permut(n,k)

Note:

The number of ways of rearranging the k elements picked from a set of n different objects.

Parameters:

n	An integer that is the number of the objects
k	An integer that is the number of the objects in each permutation

Retrun value:

The number of permutations

Example:

permut(5,4)

120

pfind()[1035][1036]

Here’s how to use pfind() function.

A.pfind()[1037][1038]

Description:

Get the sequence number of a record by its primary key.

Syntax:

A.pfind(k)

Note:

The function gets the sequence number of a record whose primary key value is k. Report error if the key isn’t set; return 0 if the eligible record can’t be found.

Parameters:

A	Record sequence/table sequence
k	Primary key; multiple field values from a composite primary key will be presented in sequence [k₁,k₂,…] or (k₁,k₂,…).

Options:

@b	Enable the binary search which requires that A must be ordered by the key, otherwise the result will be wrong.
@s	Return the opposite number of an insertable position number when the eligible record cannot be found

Return value:

The sequence number of the eligible record

Example:

	A
1	=demo.query("select * from EMPLOYEE")
2	=A1. keys (NAME,DEPT)
3	=A1.pfind(["Alexis","Sales"])	7; use a sequence to represent the value of a multi-field primay key
4	=demo.query("select * from EMPLOYEE")
5	=A4.keys(EID)
6	=A4.pfind@b(3)	3; @b is used to enable the binary search in order to speed up the computation
7	=demo.query("select * from EMPLOYEE where GENDER='M'")
8	=A7.keys(EID)
9	=A7.pfind@s(7)	-2; Return the opposite number of an insertable position number when the record in which EID=7 cannot be found

Related functions:

A.find()

pi()[1039][1040]

Description:

Compute the circumference-to-diameter ratio or its multiple.

Syntax:

pi(numberExp)

Note:

The function computes the circumference-to-diameter ratio or its multiple. The default value of numberExp is 1.

Parameters:

numberExp

The number of times. If this parameter is not supplied, the function returns the circumference ratio.

Return value:

Circumference ratio or its multiple

Example:

pi()	3.141592653589793
pi(2)	6.283185307179586

pivot()[1041][1042]

Here’s how to use pivot() function.

A.pivot(g,…;F,V;N_i:N'_i,…)[1043][1044]

Description:

Perform row-to-column transposition for a sequence.

Syntax:

A.pivot(g,…;F,V;N_i:N'_i,…)

Note:

According to grouping fields/expression g, the function transfers values Ni in F field in each group as new field names N'_i to perform a row-to-column transposition, and reassigns values of V field to the new fields. By default, N_iincludes non-duplicate values in F field; when N'_i is omitted , just use N_i.

Parameters:

A	A sequence
g	Grouping fields/expressions
F	A to-be-transposed field in the specified sequence
V	A field in the specified sequence
N_i	Values of F field
N'_i	The new name of N_ifield

Options:

Transpose rows to columns. In this case the default fields in N_iare the fields of A that are not included in g. Perform column-to-row transposition, where field names N_i are transposed as values of F field; when parameter N'_i is present, it will be values of F field and values of original N_ifield will be assigned to new field V . In this case the default values of N_iare all fields in sequence A except for grouping field g

Return value:

A sequence/record sequence

Example:

	A
1	*=demo.query("select from SCORES")**
2	=A1.pivot(CLASS,STUDENTID;SUBJECT,SCORE;"English":"ENGLISH","Math","PE")	Transpose values of SUBJECT column English, Math and PE to new fields, in which the new name of English field is ENGLISH; values of original SCORE field will be reassigned to the new fields
3	=A1.pivot(CLASS,STUDENTID;SUBJECT,SCORE;"English","Math","PE")	N'_Iis omitted
4	=A1.pivot(CLASS,STUDENTID;SUBJECT,SCORE)	Both N_i and N'_i are omitted, and values of N_i are by default the distinct values of the original SUBJECT field
5	=A2.pivot@r(CLASS,STUDENTID;SUBJECT,SCORE;ENGLISH:"English",Math,PE)	column-to-row transposition; make columns ENGLISH, Math and PE values of SUBJECT field; and values of original ENGLISH, Math, PE fields values of column SCORE
6	=A2.pivot@r(CLASS,STUDENTID;SUBJECT,SCORE)	N_i is omitted; its values are by default all the original field names except for CLASS and STUDENTID

pmax()[1045][1046]

Here’s how to use pmax() function.

A.pmax()[1047][1048]

Description:

Get the positions of members with the maximum value in a sequence.

Syntax:

A.pmax( x)

Note:

The function computes expression x with each member of sequence A and returns the sequence numbers of the members whose computations are the maximum. Can be used to find positions of the maximum value in a sequence.

Parameters:

A	A sequence
x	A field name or an expression, in which "~" is used to reference the current record.

Options:

@a	Return one sequence number or multiple ones s of the members that make expression x get the largest value. When omitted, only return the sequence number of the first member.
@z	Perform the search backwards from the last member; by default perform the search from the first member.

Return value:

A sequence number or a sequence composed of sequence numbers

Example:

	A
1	[2,5,4,3,2,9,4,9,3]
2	=A1.pmax(~*~)	6
3	=A1.pmax@a(~*~)	[6,8]
4	=A1.pmax@z(~*~)	8
5	=A1.pmax@az(~*~)	[8,6]
6	=demo.query("select * from EMPLOYEE ")
7	=A6.pmax(BIRTHDAY)	472

Related functions:

A.maxp()

A.pmin()

pmin()[1049][1050]

Here’s how to use pmin() function.

A.pmin()[1051][1052]

Description:

Get the positions of members with the minimum value in a sequence.

Syntax:

A.pmin(x)

Note:

The function computes expression x with each member of sequence A and returns the sequence numbers of the members whose computations are the minimum. Can be used to find the positions of the minimum value in a sequence.

Parameters:

A	A sequence
x	A field name or an expression, in which "~" is used to reference the current record.

Options:

@a	Return one sequence number or multiple ones of the members that make expression x get the smallest value.
@z	Perform the search backwards from the last member; by default perform the search from the first member.

Return value:

A sequence number or a sequence composed of sequence numbers

Example:

	A
1	[2,5,4,3,2,1,4,1,3]
2	=A1.pmin(~*~)	6
3	=A1.pmin@a(~*~)	[6,8]
4	=A1.pmin@z(~*~)	8
5	=A1.pmin@az(~*~)	[8,6]
6	=demo.query("select * from EMPLOYEE")
7	=A6.pmin(BIRTHDAY)	296

Related functions:

A.minp()

A.pmax()

pos()[1053][1054]

Here’s how to use pos() function.

A.pos()[1055][1056]

Description:

Get the position of a member in a sequence.

Syntax:

A.pos(x)

Note:

The function locates member x in sequence A where x may appear repeatedly. Return null if the member cannot be found; return different values according to different options.

Parameters:

A	A sequence object or an expression that returns one.
x	A member.

Options:

@b	Use the binary search to query the location. In this case A is by default an ordered sequence. Both increasing and decreasing are applicable.
@a	Return an n-integer sequence consisting of sequence numbers of all the members that fulfill the query condition.
@z	Perform the search backwards from the last member; by default perform the search from the first member.
@s	With an ordered A and the binary search, return the position of x if it is a member of A; otherwise, return the opposite number for the sequence number representing the position where x can be inserted sequentially.
@p	Find position of the sequence x, which needs to be treated as a single value, in A, which, in this case, is a sequence of sub-sequences.
@n	Return the result of the length of A plus 1 if x cannot be found in A. This option and @a are mutually exclusive.

Return value:

A sequence number or a sequence composed of sequence numbers

Example:

	A
1	=[1,2,8,4,5,6,7,8]
2	=A1.pos(8)	3
3	=A1.pos@a(8)	[3,8]
4	=A1.pos@z(8)	8
5	=A1.pos@az(8)	[8,3]
6	=A1.pos@z(9)	null
7	=[1,2,3,4,5,6,7,8].pos@b(5)	5
8	=[1,2,4,5,6,7,8].pos@s(3)	-3
9	=[[6,2,1,4,6,3,7,8],[1,4,6]].pos@p([1,4,6])	2
10	=[6,2,1,4,6,3,7,8].pos@n(5)	9

Note:

If A is not ordered, then options @b and @s should not be used, or they may bring about the incorrect results. For example:

[7,6,1,2,3].pos@b(3)

Return null

Related functions:

A.pos(x)

A.psort()

A.pos(x)[1057][1058]

Description:

Get the positions of sequence members in another sequence.

Syntax:

A.pos(x)

Note:

x is a sequence. The function returns integer sequence p which satisfies A(p)==x, and returns null if it cannot find the positions for all members of x.

Parameters:

A	A sequence
x	A sequence

Options:

@i	Return a monitonically increasing integer sequence p which satisfies A(p)==x
@c	Return the position in which sequence x first appears in A. By doing so, the position of sub-sequence x in sequence A can be located. If x is not the sub-sequence of A, then return null.
@b	Use the binary search to query the location. In this case A is by default assumed as an ordered sequence. Both Increasing and decreasing are applicable

Return value:

A monotonically increasing integer sequence or an integer sequence

Example:

[6,2,1,4,6,3,7,8].pos@i([1,4,6])	[3,4,5], which is a monitonically increasing integer sequence
[6,2,1,4,6,3,7,8].posi([1,4,6])	[3,4,1], which is an integer sequence
[1,2,3,4,6,7,8].pos@b([3,1,4,6])	[3,1,4,5]
[2,1,4,6,3,7,8].pos@i([8,4,6])	null
[2,1,4,6,3,7,8,4,6,1].pos@c([4,6])	[3]

Related functions:

A.pos()

A.psort()

pos()[1059][1060]

Description:

Get the position of a substring in its parent string.

Syntax:

pos(s1, s2{, begin})

Note:

The function finds the position of substring s2 in the parent string s1, which starts from the position begin, and returns null if the substring cannot be found.

Parameters:

s1	The parent string where you want to search for the substring.
s2	Substring of interest.
begin	The position from which the search starts; the default search is from the beginning.

Options:

@z	Perform the search leftward starting from begin, while the search will be done rightward by default.

Return value:

Integer type

Example:

pos("abcdef","def")	4
pos("abcdefdef","def",5)	7
pos("abcdef","defa")	(null)
pos@z("abcdeffdef","def",7) pos("abcdeffdef","def",7)	4 8

power()[1061][1062]

Description:

Perform exponentiation or find the n^th root of a number.

Syntax:

power(x, n)

Note:

The function computes number x raised to the n^th power, or takes an n^th root of x; if parameter n’s value is a reciprocal (1/n), the function finds the root .

Parameters:

x	Base
n	Power; default is 2

Return value:

Numeric type

Example:

power(2,4)

power(16,1/4)

16.0

2.0

power(5)

Related functions:

exp(n)

prior()[1063][1064]

Here’s how to use prior() function.

r.prior()[1065][1066]

Description：

Among the records, query fields referred by the foreign key recursively.

Syntax:

r.prior(F_,r'_,n)

Note：

The function recursively queries field F referred by the foreign key, like [r,r. F, r. F. F,…] in record r. The query will not stop until the value of field F is equal to r'. If r == r' , then return [].The default value of r' is NULL. The recursive query will be performed through all the records to the end. If the specified record r' does not exist, then return NULL. n is the maximum recursion depth, its value is 1,000 by default.

Parameters：

r	Records
F	Field name
r'	A record
n	A Number

Return value：

A sequence

Example：

	A
1	=file("D://emp.txt").import@t().keys(empid)
2	>A1.switch(mgrid,A1:empid)
3	=A1.select@1(name=="Kitty").prior(mgrid)	Based on mgrid field referred by the foreign key , select all records of people who are superior to Kitty
4	=A1.select@1(name=="Kitty").prior(mgrid,A1.select@1(name=="Tiger"),5)	Judge if Tiger is superior to Kitty and list all records of people superior to Barnes but inferior to Tiger

proc()[1067][1068]

Here’s how to use proc() function.

db.proc()[1069][1070]

Description:

Call a database stored procedure.

Syntax:

db.proc( sql, param:type:mode:variable, ... )

Note:

The function calls a database stored procedure and sends its output variables to a cellset file. The output variables can be entered into the current context and their generated values can thus be referenced by the current cellset program.

Parameters:

db	Database connection object
sql	The statement for executing a stored procedure, like call test(?,?)
param	The value of an input parameter.
type	The data type of the parameter
mode	"i" or "o". "i" indicates an input parameter and "o" indicates an output parameter.
variable	The output variable's name, through which the result of executing the stored procedure can be referenced in a cellset file.

Values for type:

public final static byte DT_DEFAULT = (byte) 0; // By default, perform automatic recognition.

public final static byte DT_INT = (byte) 1;

public final static byte DT_LONG = (byte) 2;

public final static byte DT_SHORT = (byte) 3;

public final static byte DT_BIGINT = (byte) 4;

public final static byte DT_FLOAT = (byte) 5;

public final static byte DT_DOUBLE = (byte) 6;

public final static byte DT_DECIMAL = (byte) 7;

public final static byte DT_DATE = (byte) 8;

public final static byte DT_TIME = (byte) 9;

public final static byte DT_DATETIME = (byte) 10;

public final static byte DT_STRING = (byte) 11;

public final static byte DT_BOOLEAN = (byte) 12;

public final static byte DT_INT_ARR = (byte) 51;

public final static byte DT_LONG_ARR = (byte) 52;

public final static byte DT_SHORT_ARR = (byte) 53;

public final static byte DT_BIGINT_ARR = (byte) 54;

public final static byte DT_FLOAT_ARR = (byte) 55;

public final static byte DT_DOUBLE_ARR = (byte) 56;

public final static byte DT_DECIMAL_ARR = (byte) 57;

public final static byte DT_DATE_ARR = (byte) 58;

public final static byte DT_TIME_ARR = (byte) 59;

public final static byte DT_DATETIME_ARR = (byte) 60;

public final static byte DT_STRING_ARR = (byte) 61;

public final static byte DT_BYTE_ARR = (byte) 62;

public final static byte DT_CURSOR = (byte) 101;

public final static byte DT_AUTOINCREMENT = (byte) 102;

Example:

Ø Return a record through a stored procedure

	A
1	=orac.proc("{call RQ_TEST_CUR(?,?)}",:101:"o":table1,1:0:"i":)
2	=table1	A2 references the result of executing the stored procedure via the output variable table1 in A1.It gets the same result as A1.

Here’re the contents of the stored procedure:

Ø Return table sequences through a stored procedure

	A
1	=orac.proc("{call proAA(?,?)}",:101:"o":a,:101:"o":b)	[[7369,7499,7521,…],[1,2,3]]. Return a sequence of table sequences; each table sequence is referenced by an output variable
2	=A1(1)	Return the first table sequence in the sequence of A1
3	=a	A3 and A4 get stored procedure results by referencing the output variables in A1
4	=b

Here’re the contents of the stored procedure:

Related functions:

db.execute()

db.query()

product()[1071][1072]

Description:

Return the product of a set of numbers.

Syntax:

product(x_i,…)

product(A)

Note:

The function multiplies the members of [x₁, x₂,…], where any member that is not a number will be ignored.

Parameter:

A	A sequence
x_i	An expression

Example:

	A
1	=product(17,3,5)	255
2	=product(4,"b",12,2)	96

property()[1073][1074]

Here’s how to use property() function.

f.property()[1075][1076]

Description:

Retrieve property value from the property file.

Syntax:

f.property(p)

Note:

The function retrieves property p from property file f and return.

Parameters:

f	File object
p	Property name; the function returns a table sequence composed of all properties if it is omitted

Options:

@v	Read a property value and parse it as what it is; by default return the value as a string.

Return value:

A value/a table sequence

Example:

	A
1	=file("E://test.property").property("color")	Property file, export”red”
2	=file("E://test.property").property()

Related functions:

f.read()

f.write()

pseg()[1077][1078]

Here’s how to use pseg() function.

A.pseg(x,y)[1079][1080]

Description：

Return the sequence number of the interval in which the parameter falls.

Syntax：

A.pseg(x,y)

Note：

The function returns the sequence number of the interval in which y falls in sequence A, which must be an ordered one. By default the sequence members form intervals that are left-closed and right-open. Parameter x is an expression which will be calculated over each member of sequence A.

In the cases where y is not a member of A, if y is less than the smallest member of an increasing sequence A (or y is greater than the largest member of a decreasing sequence A), then return 0; if y is greater than or equal to the largest member of an increasing sequence A (or y is less than or equal to the smallest member of a decreasing sequence A), then return the length of A.

Parameters：

A	A sequence
x	An expression, which is a field name or a legal expression made up of field name and in which the sign ~ can be used to reference the current record; can be absent
y	An expression

Options:

@r Form intervals that are left-open and right-closed

Return value：

The sequence number of the interval to which y belongs

Example：

	A
1	[2,22,122,222,2222]
2	=A1.pseg(12)	1. The intervals formed by members of the sequence are [2,22), [22,122), [122,222), [222,2222) and [2222,∞)
3	=A1.pseg(2222)	5
4	=A1.pseg@r(2222)	4
5	[1,4,8]
6	=A5.(~+~).pseg(10)	2
7	=A5.pseg(~+~,10)	2; the expression is equivalent to A6’ s expression
8	=A1.pseg(1)	0

pselect()[1081][1082]

Here’s how to use pselect() function.

A.pselect()[1083][1084]

Description:

Get the positions of the specified members from a sequence.

Syntax:

A.pselect( x)
A.pselect(x1:y1,x2:y2,......xi:yi)	The simplified syntax for the composite query using "&&" . It is equal to A.pselect(x1==y1 && x2==y2 &&...... xi==yi).

Note:

The function returns the sequence number of a member that fulfils condition x, or returns an empty sequence/null if it cannot find the eligible member. The return value is also subject to the option working with the function.

Options:

@a	Return a sequence composed of sequence numbers of all the members that fulfill the condition x. When it is not supplied, return the sequence number of the first eligible member.
@z	Perform the search backwards from the last member; by default perform the search from the first member.
@b	Perform the binary search when A is an ordered sequence by default. Note that in this case x_i must be in ascending or descending order. If A is not an ordered sequence, this option could return incorrect result. When it is used with A.pselect(x1:y1,x2:y2,......xi:yi) to find out members that make cmp(x,y) return 0, simply write A.pselect@b(x1:y1,x2:y2,......xi:yi) without including cmp().
@s	It requires that members in A are ordered for expression x. With the binary search, if no members in A can make the expression x return 0, then return the opposite number of the position where x can be inserted.
@n	If no sequence member is found, return the result of the length of A plus 1. This option and @a are mutually exclusive

Parameters:

A	A sequence
x	A boolean expression, whose value can be null. When using @b option, x should be an expression whose return value is an integer
xi:yi	xi is an expression, and yi is a comparing value

Return value:

The sequence numbers of the member that fulfils condition x or that makes the result of expression x equals y in the given sequence. @a option works to return a sequence composed of all the sequence numbers of the member that fulfils condition x, and return a sequence composed of the sequence numbers of all the members when x is null.

Example:

	A
1	[2,5,4,3,2,9,4,9,3]
2	=A1.pselect(~>4)	2
3	=A1.pselect@a(~>4)	[2,6,8]
4	=A1.pselect@z(~>4)	8
5	=A1.pselect@az(~>4)	[8,6,2]
6	=[1,3,5,7,9].pselect@b(~-5)	3. The syntax of A8 and A9 are equal, and their return values are the same. When using a colon, the syntax of using @b doesn’t need to be changed
7	=[1,3,5,7,9].pselect@b(~:5)
8	=[1,3,5,7,9].pselect@s(~:4)	-3. Cannot find 4 and return the opposite number of the position where 4 can be inserted
9	=[1,3,5,7,9].pselect@n(~:4)	6
10	=demo.query("select * from EMPLOYEE")
11	=A10.pselect(GENDER:"M",DEPT:"Sales")	6
12	=demo.query("select * from EMPLOYEE where GENDER='M' order by EID asc")	EID and GENDER are in the same order
13	=A12.pselect@b(EID:10,GENDER:"M")	2
14	=A12.pselect@s(EID:3,GENDER:"M")	-1. Cannot find the record satisfying EID=3 and GENDER=M and return the opposite number of the position where the record can be inserted
15	=A12.pselect@n(EID:3,GENDER:"M")	239

Note:

If A is not an ordered sequence, and xi is not in ascending or descending order, the use of options @b and @s may bring about incorrect results.

Related functions:

A.select()

psort()[1085][1086]

Here’s how to use psort() function.

A.psort()[1087][1088]

Description:

Get the original positions of the sorted members of a sequence.

Syntax:

A.psort (x)

A.psort(xi,...)

Note:

The function sorts members of sequence A according to the value of expression x and returns their sequence numbers before they are sorted.

Parameters:

A	A sequence
x	The sorting expression
xi	If there are multiple sorting expressions, they can be written as xi,.., a compound expression consisting of multiple expressions. The function sorts members by xi,… sequentially in ascending order by default. - xi means sorting in descending order

Options:

@m Perform parallel algorithm to enhance performance of handling data-intensive or computation-intensive tasks.

@z	Sort a sequence in descending order and return the position of a member in the original sequence
@0	Put records with null values at the end

Return value:

A sequence composed of the sequence numbers of all the members in a given sequence before they are sorted by expression x.

Example:

	A
1	[a,c,e,g,f,d,b]
2	=A1.psort(~)	[1,7,2,6,3,5,4]
3	=demo.query("select * from EMPLOYEE")
4	=A3.psort(DEPT,BIRTHDAY)	A3 is sorted in ascending order by DEPT first, and then in descending order by BIRTHDAY.
5	=A3.psort@m(DEPT,BIRTHDAY)	Use @m opton to increase performance of big data handling.
6	=A1.psort@z(~)	[4,5,3,6,2,7,1]
7	[a,c,e,,f,d,b]
8	=A7.psort(~)	[4,1,7,2,6,3,5]
9	=A7.psort@0(~)	[1,7,2,6,3,5,4]

Related functions:

A.pos()

A.sort()

A.pos(x)

A.swap(p,q)

A.rvs()

ptop()[1089][1090]

Here’s how to use ptop() function.

A.ptop()[1091][1092]

Description:

Get the sequence numbers of the n smallest members in a sequence.

Syntax:

A.ptop(n,x)

Note:

The function sorts members of sequence A according to expression x and returns a sequence comprising the sequence numbers of the n smallest members in the given sequence. List both if the smallest member and the largest member are the same. n must be supplied; if n is 0, return null. The absence of x is equivalent to ~; and if the value of x is 0, sorting action won’t be performed.

Parameters:

A	A sequence
x	Sorting expression
n	An integer

Options:

@1	Return a single value if n is ±1

Return value:

A sequence composed of sequence numbers of specified members

Example:

	A
1	[a,c,e,g,f,d,b]
2	=A1.ptop(3,~)	[1,7,2]
3	=A1.ptop(3)	Same as A2, as x is not supplied
4	=demo.query("select * from EMPLOYEE")
5	=A4.ptop(3,HIREDATE)	[8,18,203]
6	=A1.ptop(-1)	4
7	=A4.ptop(3,0)	[1,2,3]
8	=A1.ptop@1(-1)
9	[a,c,e,g,f,d,b,a]
10	=A9.ptop(1,~)	[1,8]

Related functions:

push()[1093][1094]

Here’s how to use push() function.

A.push()[1095][1096]

Description:

Push data in a given sequence into a channel.

Syntax:

A.push(ch_i ,…)

Note:

The function pushes data in sequence A into channel ch_iand returns the sequence itself. Unless a function that gets the final result set is attached to the channel, the final result set can’t be retrieved from it as the sequence is pushed in.

Parameters:

A	A sequence
ch_i	Channel

Return value:

Sequence

Example:

	A
1	=demo.query("select * from SALES")
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A2.groups(SELLERID:SellerId;sum(AMOUNT):Amount)	Attach ch.groups() operation that gets the final result to A2’s channel
5	=A3.select(ORDERID<10)	A3 attaches ch.select() operation to A2’s channel
6	=A3.fetch()	Attach ch.fetch() function that gets the final result to A3’s channel to fetch and store the existing data
7	=A1.push(A2,A3)	Push data in A1’s sequence into A2’s channel and A3’s channel
8	=A2.result()	Get results from A2’s channel
9	=A3.result()	Get results from A3’s channel

Related functions:

ch.push()

cs.push()

channel()

ch.push()[1097][1098]

Description:

Push data in a channel into another channel.

Syntax:

ch.push(ch_i ,…)

Note:

The function pushes data in channel ch into channel ch_i, and returns channel ch itself.

Parameters:

ch	Channel
ch_i	Channel

Return value:

Channel

Example:

	A
1	*=demo.cursor("select from SALES")**	Create a channel
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A2.select(ORDERID>100)	Attach ch.select() operation to A2’s channel
5	=A1.push(A2)	Push data in A1’s cursor into A2’s channel
6	=A2.push(A3)	A3 Push data in A2’s channel into A3’s channel
7	=A2.fetch()	Attach ch.fetch() function that gets the final result set to A2’s channel to fetch and store the existing data
8	=A3.groups(SELLERID:SellerId;sum(AMOUNT):Total)	Attach ch.groups() operation to A3’s channel
9	=A1.groups(SELLERID:SellerId;sum(AMOUNT):Total)	Data in A1’s cursor is actually pushed into the channel as the operation begins
10	=A2.result()	Get results from A2’s channel
11	=A3.result()	Get results from A3’s channel

Related functions:

A.push()

cs.push()

channel()

cs.push()[1099][1100]

Description:

Push data in a cursor into a channel.

Syntax:

cs.push(ch_i ,…)

Note:

The function pushes data in cursor cs into channel ch_i, but the action needs to wait until the data in the cursor is fetched; then returns the cursor itself. The function supports multicursors.

Parameters:

cs	Cursor
ch_i	Channel

Return value:

Cursor

Example:

	A
1	=demo.cursor("select * from SALES")	Create a cursor
2	=channel()	Create a channel
3	=channel()	Create a channel
4	=A2.groups(SELLERID:SellerId;sum(AMOUNT):Total)	Perform ch.groups() operation in the channel
5	=A3.select(ORDERID<10)	Attach ch.select() operation to A3’s channel
6	=A3.fetch()	Fetch and store the existing data in the channel
7	=A1.push(A2,A3)	Be ready to push data in A1’s cursor into the channel, but the action needs to wait
8	=A1.groups(SELLERID:SellerId;sum(AMOUNT):Total)	Data in A1’s cursor is pushed into the channel as the data retrieval operation begins
9	=A2.result()	Get results from A2’s channel
10	=A3.result()	Get results from A3’s channel

	A
1	=demo.cursor("select * from SALES")	Create a cursor
2	=channel()	Create a channel
3	=A2.select(ORDERID>100)	Attach ch.select() operation to the channel
4	=A2.fetch()	Keep data in the channel
5	=A1.push(A2)	Be ready to push A1’s cursor data to the channel
6	=A1.fetch()	Fetch data from A1 cursor when the cursor data is really pushed into the channel and the operations in the channel are executed
7	=A2.result()	Fetch the final result set from the channel

Related functions:

ch.push()

A.push()

channel()

query()[1101][1102]

Here’s how to use query() function.

db.query()[1103][1104]

Description:

Execute a SQL statement on a data source and return a table sequence composed of the query results.

Syntax:

db.query( sql {,args …})
db.query(A,sql{,args …})	Perform sql based on A and return a table sequence composed of query results. Here, args can be an expression evaluated based on each member of A. This type of syntax can work with @idx options.
db.query(call dfx(){,args …})	Connect to esProc-ODBC data source db to call the specified dfx file and return a result

Note:

The function performs the specified SQL query sql on the data source db and returns a table sequence composed of query results. db is the database connection object.

When there’s only one table following FROM in the SQL statement sql, the key of the result table sequence will be automatically set.

Parameters:

db	Database connection object.
sql	A SQL statement, like select * from table.
args	An argument value passed into the specified SQL command sql. It can be a constant or an expression. The comma is used to separate multiple arguments.
A	A sequence. sql is executed on each member of A. Generally args is computed against each member of A and the value is passed to sql for execution.
dfx	A cellset file; can be specified using a relative path, which is relative to the search path, or an absolute path

Options:

@1	Return only the first-found record satisfying the condition, which is a single value if only one field is involved or a sequence if multiple fields are involved.
@i	Return a sequence if the result set has only one column.
@d	Convert the numeric data type to the double data type, instead of the decimal data type.
@x	Close the database connection automatically when the statement finishes execution. Only valid with the database connection established through the connect function.

Return value:

A table sequence composed of results of executing sql.

Example:

	A
1	=demo.query("select * from EMPLOYEE where DEPT=? ","Sales")
2	=demo.query@1("select * from EMPLOYEE where DEPT=? ","Sales")	[3,"Rachel","Johnson","F","New Mexico",1970-12-17,2010-12-01,"Sales",9000]; with @1 option, a sequence composed of field values of the first record is returned.
3	[1,2,3,4]
4	=demo.query(A3,"select * from EMPLOYEE where EID=?",~)
5	=demo.query@i(A3,"select SURNAME from EMPLOYEE where EID=?",~)	Return the result as a sequence
6	=demo.query@i("select DEPT from DEPARTMENT")	Return the result as a sequence
7	=mysql.query@d("select * from ta")
8	=connect("demo")
9	=A8.query@x("select DEPT from DEPARTMENT")	Close the database connection automatically when the execution is over.
10	=myproc.query("call hsql(?)",10)	hsql.dfx is in the search path. Below is the file: myproc is the esProc-ODBC data source name; the parameter value is 10. Below is the result:
11	=myproc.query("call G://hsql(?)",10)	hsql.dfx is in the root directoy on drive G; same content and same result as shown in A10

Related functions:

db.execute()

db.proc()

db.query(sql)[1105][1106]

Description:

Query an external table using simple SQL and return the query result.

Syntax:

db.query( sql {,args …})

Note:

The function performs a query over an external data file. As a normal table sequence, the external file can be direcly queried by using “file name.extension” as its name, which makes it the external table. The query syntax, which we call simple SQL, is similar to the SQL syntax for the database query.

Support external data files in the format of txt, csv, xlsx, xls, btx (bin files) and ctx(composite table files). An external data table file has headers by default. Use a relative path or an absolute path to access the external data table file; the relative path is relative to esProc main directory.

Parameters:

db	Use connect() to connect to a file system
sql	A “simple SQL” statement, like *select from filename.txt**
args	A parameter used in a simple SQL statement, which must be assigned value; multiple parameters should be separated by the comma.

Syntax of simple SQL:

with T as (x)	Define an external table through an esProc script; the query over the file x returns a table sequence or a cursor.
select x F,…	Select data from an external table where x is a field or an expression and F is the alias of the field.
from T T’	Use a defined external table T; T’ is the alias of this table and can be omitted.
from fn T	Direclty use file fn, whose format can be txt, csv, xls, xlsx, btx (a bin file) and ctx (a composite table file) as the external table T; the file is opened as a cursor, and by default has headers; use a relative path, which is relative to esProc main directory, or an absolute path to access file fn.
from {x} as	x is an expression that can be executed within the current cell; the expression should be an esProc expression that returns a table sequence or a cursor Can use as before the alias of an external file.
where	For conditional filtering.
join,left join,full join	Associative operations that handle all data in the memory; the corresponding function is xjoin().
/ parallel (n) /	Perform a parallel processing when there isn’t a join and when the external file is a bin file/a composite table.
group by	For grouping operation with groups() function, whose result set is supposed to be able to be wholly stored in the mermoy.
group by n	Perform grouping by the nth expression in the select statement; n should be a constant.
having	For filtering on grouped data.
order by	For sorting operations in ascending order, by default.
order by n	Perform sorting by the nth expression in the select statement; n should be a constant.
distinct	Synonym of SQL DISTINCT clause; support only a single table and doesn’t support count( distinct ).
and, or, not, in ,is null, case when else end between	Used in SQL style; in only supports sets of constants and doesn’t support subqueries A data range sandwiched by two values, such as the value f1 that falls between 1 and 3, which can be written as f1 >= 1 && f1 <= 3
like into fn	Fuzzy query, which supports the following wildcard characters: % Match multiple characters _ Match a single character [chracter,…] A character list that matches any single character in the list [!chracter,…] or [^chracter,…] Won’t match any single character in the character list Write the result set to file fn, whose format is determined by its extension, which can be txt, csv, btx, xls and xlsx; use a relative path, which is relative to esProc main directory, or an absolute path to access file fn
? and ?i	Parameters in the simple SQL statement; i represents the i^th parameter
insert	Append data to a file/vector; a composite table to which data is appended must be ordered by the dimension
update	Update data; only support composite tables and the WHERE clause must use the key
delete	Delete data; only support composite tables and the WHERE clause must use the key
commit	Updated data will be temporarily stored but won’t be executed until the commit action is performed; then the new data can be retrieved
rollback	Give up the latest update
aggregate functions	including sum, count, max, min and avg (without support for count(distinct) at present).
set operations	union, union all,intersect,minus; the computation is handled all in the memory
subquery	All subqueries are executed in memory except the from statement
top n	Get first n records
limit n offset m	Skip m records to get n records
Other functions	esProc functions conforming to the syntax
*String functions*
LOWER(str)	Convert into lower case
UPPER(str)	Convert into upper case
LTRIM(str)	Delete whitespaces on the leftmost side
RTRIM(str)	Delete whitespaces on the rightmost side
TRIM(str)	Delete whitespaces on both sides
SUBSTR(str,start,len) SUBSTR(str,start)	Return a substring
LEN(str)	Return the length of a string
INDEXOF(sub,str[,start])	Return the position of a substring
LEFT(str,len)	Return the substring in the left of a specified string
RIGHT(str,len)	Return the substring in the right of a specified string
CONCAT(str1,str2)	Concatenate two strings
CONCAT(s1,s2,…)	Concatenate multiple strings
REPLACE(str,sub,rplc)	Replace a substring by another string
*Nemeric functions:*
ABS(x)	Return absolute value
ACOS(x)	Return arc cosine
ASIN(x)	Return arc sine
ATAN(x)	Return arc tangent
ATAN2(x,y)	Return arc tangent
CEIL(x)	Return the smallest integer that is not less than x
COS(x)	Return cosine value
EXP(x)	Return the base of e to the power of x
FLOOR(x)	Return the biggest integer that not greater than x
LN(x)	Return the natural logarithm
LOG10(x)	Return the logarithm with base 10
MOD(x,m)	Return the remainder of x divided by m
POWER(x,y)	Return the value of x raised to the power of y
ROUND(x,n)	Return x rounded to n digits from the decimal point
SIGN(x)	Return the sign for x
SIN(x)	Return the sine value
SQRT(x)	Return the square root of x
TAN(x)	Return the tangent value
TRUNC(x,n)	Return x truncated to n decimal places
RAND(seed)	Return a random number
*Date&Time functions:*
YEAR(d)	Return the year
MONTH(d)	Return the month
DAY(d)	Return the day of the month
HOUR(d)	Return the hour
MINUTE(d)	Return the minute from d
SECOND(d)	Return the second
QUARTER(d)	Return the quarter from d
TODAY()	Return the date
NOW()	Return the current time
ADDYEARS(d,n)	Add years
ADDMONTHS(d, n)	Add months
ADDDAYS(d, n)	Add days
ADDHOURS(d, n)	Add hours
ADDMINUTES(d, n)	Add minutes
ADDSECONDS(d, n)	Add seconds
DAYOFYEAR(d)	Return the day of year
WEEKOFYEAR(d)	Return the calendar week of the date
*Conversion functions:*
ASCII(str)	Return numeric value of left-most character
CHR(n)	Return the chracter for integer n
INT(x)	Return an integer for string or number x
DECIMAL(x,len,scale)	Return the numeric value for a string or number
TIMESTAMP(str)	Convert the format string of yyyy-mm-dd hh24:mi:ss into datetime
NUMTOCHAR(d)	Return a string for number d
DATETOCHAR(date)	Convert date into a string in the format of yyyy-mm-dd hh24:mi:ss
*Others:*
NULLIF(x1,x2)	Return null if x1=x2, otherwise return x1
COALESCE(x1,…)	Return the first non-null parameter
COUNTIF(x1,…,xn)	Count the number of data objects that meet the specified criteria

Return value:

A table sequence

Example:

	A
1	=connect()
2	*=A1.query("select from Persons.txt")**
3	*=A1.query("select from D:/Orders.txt")**
4	=A1.query("select Id_P, sum(OrderNo) from Orders.csv group by 1 ")	Group by Id_P field
5	=A1.query("select Id_P, OrderNo from Orders.csv order by 2 ")	Sort by OrderNo field in ascending order, by default
6	*=A1.query("select into p1.txt from Persons.csv ")**	Write the query result set to the file p1.txt
7	*=A1.query("select from Persons.csv where Id_P=? or Id_P>? ",2,2)**	Retrieve records where Id_P is equal to or greater than 2
8	*=A1.query("select from Persons.csv where Id_P=?1 or Id_P>?2 ",2,2)**	Retrieve records where Id_P is equal to or greater than 2; ?i represents the i^th parameter
9	*=A1.query("with persons as (file(\"D:/Persons.btx\").import@b()) select from persons ")**	Perform a query over Persons.btx and name the result set persons, and then perform a second query over persons; this is an optimization way for processing huge data in SQL
10	*=A1.query("select /+parallel(20)/ count() from Persons.btx")**	Count the records in the external table Persons.btx in parallel
11	*=A1.query("select from Persons.txt P join Orders.txt O on P.Id_P = O.Id_P ")**	Perform a query through a join
12	=A1.query("select distinct(Id_P),name from Orders.txt ")	Get records where Id_P values are unique
13	=A1.query(“select CASE id_P when 1 then 'one' when 2 then 'tow' else 'other' end from p1.txt”)	Here the case when statement is used
14	=A1.query("select * from Persons.ctx where city like 'N%' ")	Use like syntax to find from the file Persons.ctx the record where the first character of the city field is N
15	=A1.query("select * from Persons.ctx where Name like '_a_t%' ")	Use like syntax to find from the file Persons.ctx the record where the second character of the Name field is a
16	=A1.query("select * from Persons.ctx where Name like '%[us]%' ")	Use like syntax to find from the file Persons.ctx the record where the Name field contains u or s
17	=A1.query("select * from Persons.ctx where Name like '%[!a]%' ")	Use like syntax to find from the file Persons.ctx the record where the Name field doens’t contain character a
18	=A1.query("select * from Persons.ctx where Name like '%[^s]%' ")	Use like syntax to find from the file Persons.ctx the record where the Name field doens’t contain character s

	A
1	=connect()
2	=A1.query("select * from Dep.txt ")
3	=A1.query("insert into Dep.txt values ('ABC',11)")	The insert statement appends data to Dep.txt
4	=A1.query("commit")	The appended data is temporarily stored and can’t be retrieved until the commit action is executed
5	=A1.query("select * from ctb.ctx")
6	=A1.query("insert into ctb.ctx values (8,80)")	Append a record to the composite table
7	=A1.query("update ctb.ctx set v1=20 where k1=2")	Update the composite table according to the key k1
8	=A1.query("delete from ctb.ctx where k1=11")	Delete the record where k1 is 11 from the composite table, in which k1 is the key
9	=A1.query("delete from ctb.ctx where k1=10")	Delete the record where k1 is 10 from the composite table, in which k1 is the key
10	=A1.query("rollback")	The rollback action gives up the latest update
11	=A1.query("commit")	The commit action
12	=A1.query("select * from ctb.ctx")	The updated composite table: Since A10 performs a rollback action, the deletion of reocrd where k1 is 10 is canceled

	A
1	=file("score1.txt")
2	=file("score2.txt")
3	=A1.cursor@t()
4	=A2.cursor@t()
5	=[A3, A4].mcursor@t()
6	=connect().query("select CLASS, max(SCORE) avg_score from {A5} where SUBJECT='math' group by CLASS")	Use from {x} syntaxt, where x is a cursor

r(T,F)^{^[1107]}^{^[1108]}

Description:

Find a certain field of a specified row in a table sequence/memory table.

Syntax:

k.r(T,F)

Note:

The function finds F field of row k in table sequence/memory table T, which is equivalent to T(k).F. Won’t check whether k is within T’s length.

Parameters:

k	Row number
T	A table sequence/memory table
F	A field of T; can be omitted

Return value:

A record

Example:

	A
1	=demo.query("select EID,NAME from employee")
2	=1.r(A1,NAME)	Get the Name value in the first row of A1’s table sequence
3	=1.r(A1)	Since parameter F is absent, list all field values of the first row

r.(x)[1109][1110]

Description:

Compute an expression against a record and return the result.

Syntax:

r.( x )

Note:

The function computes the expression x against record r, and return the result.

Parameters:

r	A record
x	An expression, which is generally a field name or a legal expression that is composed of field names. Use "~" to reference the current record.

Return value:

The computation of x

Example:

	A
1	=[[12,23]].new(~(1):col1,~(2):col2)
2	=A1(1).(col2+1)	24

r.F[1111][1112]

r is a record, and r.F is the value of field F of record r .

Besides using r.F to indicate field value, you can also use r.#i, of which #i means the i^th field.

r.F=x[1113][1114]

Description:

Assign value to a field of a record.

Syntax:

r.F=x

Note:

The function assigns x to field F of record r.

Parameters:

r	A record
F	Field name
x	An expression, the computation of which is the field value of F

Return value:

The computation of x

Example:

	A
1	=demo.query("select EID,NAME, SALARY from EMPLOYEE")
2	>A1(1).SALARY=A1(1).SALARY+100	The value of "SALARY " in A1(1) is changed into 7100.00

rand()[1115][1116]

Description:

Get a random number.

Syntax:

rand(n)

Note:

The function returns a random integer between 0 and 1.

Parameters:

n	An integer. Without it the function returns a random float number between 0 and 1.0

Options:

@s	Set the seed value for generating a random number.

Return value:

Numeric type

Example:

rand()	Get a random number in the range of [0, 1.0]
rand()*100	Get a random float number in the range of [0, 100]
rand(100)	Get a random integer in the range of [0, 100]

Ø The seed value for generating a random number.

	A
1	=rand@s(5)
2	=10.(rand())
3	= rand@s(5)
4	=10.(rand())	The 10 random numbers generated in A4 and A2 are identical

rands()[1117][1118]

Description:

Get a random string.

Syntax:

rands(s,l)

Note:

The function generates a string of length l randomly using the characters of string s.

Parameters:

s	A string
l	An integer

Return value:

A string

Example:

rands("abc",5)

Generate a string of length 5 with characters of string “abc”

range()[1119][1120]

Description:

Get the beginning members of the specified segment and its next segment.

Syntax:

range(s,e,k:n)

Note:

The function evenly divides an interval defined by starting data s and ending data e (both parameters can be integers) into n segments and returns the beginning member of the k^th segment and that of the (k+1)^th segment as a two-member sequence. The precision of the retunred data is determined by the date type. For example, the maximum precison date type data is day, and that of datetime data is second. If parameter k is absent, return the beginning members and ending members of all segments, which means the returned sequence will have n+1 members.

Parameters:

s	Starting data
e	Ending data
k	The k^th segment whose beginning member is to be returned
n	The number of segments data is divided

Return value:

A sequence

Example:

	A
1	=range(date("1982-08-09"),date("1992-08-09"),2:3)	The max precison of the date data is day
2	=range(datetime("2006-01-01 10:20:30:111"),datetime("20016-01-01 10:20:30:111"),2:3)	The max precison of the datetime data is second
3	=range(1,9,2:3)	Parameter s and e are integers
4	=range(date("1982-08-09"),date("1992-08-09"),3)	As parameter k is absent, return the beginning members and ending members of all segments

rank()[1121][1122]

Here’s how to use rank() function.

A.rank(y)[1123][1124]

Description:

Compute the ranking of a specified value in a sequence.

Syntax:

A.rank(y)

Note:

The function returns the ranking of a specified value y in sequence A, which by default is sorted in ascending order.

Options:

@z	Return a ranking according to members sorted in descending order. Here “z” is in lowercase.
@i	Deduplicate sequence A before getting y’s ranking.
@s	Perform average operation for each of the duplicate ranking and return the result, which could contain non-integers. Take the sequence [3,2,6,6,9] for example, a default ranking is [2,1,3,3,5]; but with @s option, the ranking becomes [2.0,1.0,(3+4)/2,(3+4)/2,5.0] after we get averages for the two duplicates.

Parameters:

A	A sequence
y	A member of sequence A

Return value:

An integer sequence composed of rankings of sequence A’s members

Example:

	A
1	=[2,1,3,4,8,5,2,0]
2	=A1.rank(6)	8; a ranking according to ascendingly ordered members
3	=A1.rank@z(6)	2; a ranking according to descendingly ordered members
4	=A1.rank@i(2)	3; deduplicate the sequence before finding the ranking
5	=A1.rank@s(2)	3.5; get averages for duplicate rankings and then return the final result

Related functions:

A.rank(y,x)

A.rank(y,x)[1125][1126]

Description:

Get the ranking of a certain member in the computed sequence.

Syntax :

A.rank(y,x)

Equivalent to A.(x).rank(y)

Note:

The function computes expression x over each member of sequence A and returns the ranking of a given value y in sequence A.(x). By default the sequence members are sorted in ascending order.

Options:

@z	Return a ranking according to members sorted in descending order. Here “z” is in lowercase.
@i	Deduplicate sequence A.(x) before getting y’s ranking.
@s	Perform average operation for each of the duplicate ranking and return the result, which could contain non-integers. Take the sequence [3,2,6,6,9] for example, a default ranking is [2,1,3,3,5]; but with @s option, the ranking becomes [2.0,1.0,(3+4)/2,(3+4)/2,5.0] after we get averages for the two duplicates.

Parameters:

x	An expression according to which sequence A is computed.
y	A member of sequence A or a value for comparing members of sequence A.(x).
A	A sequence.

Return value:

The ranking of a given member

Example:

	A
1	*=demo.query("select from SCORES where SUBJECT='English'")**
2	=A1.rank(90,SCORE)	23; a ranking according to ascendingly ordered members
3	=A1.rank@z(90,SCORE)	5; a ranking according to descendingly ordered members
4	=A1.rank@i(90,SCORE)	10; the ranking with duplicate(s) removed
5	=A1.(SCORE).rank(90)	23
6	=A1.rank@s(90,SCORE)	23.5; get averages for duplicate rankings and then return the final result

Related functions:

A.rank(y)

rank()[1127][1128]

Description:

An interative loop for numbering records according to the values of certain fields.

Syntax:

rank(F;G_i,…)

Note:

The function performs a loop operation to number records from 1 according to the value of G_ifield. With the same G_ifield value, records having the same F field value will be given the same sequence number. When the value of F field changes, the sequence number for the corresponding record is the previous sequence number plus the number of the records with that sequence number. When the value of G_ifield changes, start a new round of the numbering process.

Parameters:

F	Field name
G_i	Field name

Returned value:

Integer

Example:

	A
1	*=demo.query("select from SCORES ")**
2	=A1.derive(rank(STUDENTID;CLASS):F1)

ranki()[1129][1130]

Description:

An interative loop for numbering records according to the values of certain fields.

Syntax:

ranki(F;G_i,…)

Note:

The function performs a loop operation to number records from 1 according to the value of G_ifield. With the same G_ifield value, records having the same F field value will be given the same sequence number; add 1 to the sequence number when F field value changes. When the value of G_ifield changes, start a new round of the numbering process.

Parameters:

F	Field name; under same G_ifield value, records with same F field value have same sequence number; add 1 to the sequence number if F field value changes
G_i	Field name; in a loop function, number records under same G_ifield value by the changes of F field value; renumber a record when G_ifield value changes.

Return value:

Integer

Example:

	A
1	*=demo.query("select from SCORES ")**
2	=A1.derive(ranki(STUDENTID;CLASS):F1)

ranks()[1131][1132]

Here’s how to use ranks() function.

A.ranks(x)[1133][1134]

Description:

Get the rankings of members of sequence A.(x).

Syntax:

A.ranks(x)

Equivalent to A. (x).ranks()

Note:

The function computes expression x over each member of sequence A to return the rankings of members of sequence A.(x), which by default is sorted in ascending order.

Options:

@z	Return a ranking according to members sorted in descending order (in ascending order by default). Here “z” is in lowercase.
@i	Deduplicate sequence A.(x) before getting the rankings.
@s	Perform average operation for each of the duplicate ranking and return the result, which could contain non-integers. Take the sequence [3,2,6,6,9] for example, a default ranking is [2,1,3,3,5]; but with @s option, the ranking becomes [2.0,1.0,(3+4)/2,(3+4)/2,5.0] after we get averages for the two duplicates.

Parameters:

x	An expression according to which sequence A is computed
A	A sequence

Return value:

The rankings of members of sequence A.(x).

Example:

	A
1	=demo.query("select * from SCORES where SUBJECT='English'")
2	=A1.ranks(SCORE)	[7,9,13,1,17,5,13,19,3,25,11,21,23,25,7,9,13,1,17,5,13,19,3,25,11,21,23,25];Rank members in ascending order
3	=A1.ranks@z(SCORE)	[21,19,13,27,11,23,13,9,25,1,17,7,5,1,21,19,13,27,11,23,13,9,25,1,17,7,5,1];Rank members in descending order
4	=A1.ranks@i(SCORE)	[4,5,7,1,8,3,7,9,2,12,6,10,11,12,4,5,7,1,8,3,7,9,2,12,6,10,11,12]; rankings with duplicates removed
5	=A1.(SCORE).ranks()	Same requirement as that in A2
6	=A1.ranks@s(SCORE)	[21.0,10.0,20.0,2.0,6.0,22.0,26.0,8.0,14.0,9.0,12.0,5.0,15.0,19.0,4.0,11.0,13.0,1.0,28.0,24.0,25.0,16.0,17.0,23.0,27.0,7.0,18.0,3.0]; get averages for duplicate rankings and then return the final result

Related functions:

A.ranks()

A.ranks()[1135][1136]

Description:

Compute the ranking of each member in a sequence.

Syntax:

A.ranks()

Note:

The function obtains the ranking of each member in sequence A and returns a sequence composed of rankings of the members, which by default are sorted in ascending order.

Parameters：

A	A sequence

Options:

@z	Return a ranking according to members sorted in descending order. Here “z” is in lowercase.
@i	Deduplicate sequence A before getting the rankings.
@s	Perform average operation for each of the duplicate ranking and return the result, which could contain non-integers. Take the sequence [3,2,6,6,9] for example, a default ranking is [2,1,3,3,5]; but with @s option, the ranking becomes [2.0,1.0,(3+4)/2,(3+4)/2,5.0] after we get averages for the two duplicates.

Return value:

An integer sequence composed of rankings of sequence A’s members

Example:

	A
1	=[2,1,3,4,8,5,2,0]
2	=A1.ranks()	[3,2,5,6,8,7,3,1]; rank members in ascending order
3	=A1.ranks@z()	[5,7,4,3,1,2,5,8]; rank members in descending order
4	=A1.ranks@i()	[3,2,4,5,7,6,3,1]; rankings with duplicates removed
5	=A1.ranks@s()	[3.5,2.0,5.0,6.0,8.0,7.0,3.5,1.0] ; get averages for duplicate rankings and then return the final result

Related functions:

A.ranks(x)

read()[1137][1138]

Here’s how to use read() function.

f.read()[1139][1140]

Description:

Read contents of a file and return result as strings.

Syntax:

f.read()

Note:

The function retrieves the contents of file f and returns them as strings.

Parameters:

f A file

Options:

@n	Return the contents of the file object f as a string sequence; each row is corresponding to a member.
@v	Return a sequence as the corresponding data type. The combined use of this option and @n is acceptable

Return value:

A string

Example:


	A
1	=file("D:/score.txt")
2	=A1.read()	Read the contents of file object score.txt as a string
3	=A1.read@n()	With @n option, read and concatenate each line in the text file into a string and return it as a member of the resulting sequence
4	=file("D:/tmp2.txt")
5	=["Lucy","98"]	By default Lucy is a string and 98 is an integer
6	=A4.write(A5)
7	=A4.read@nv()	With @nv options, return a sequence consisting of rows of different data types
8	=A1.read@s()	Read the text file as the binary blob data

Related functions:

f.write()

record()[1141][1142]

Here’s how to use records() function.

T.record()[1143][1144]

Description：

Make the members of a sequence the new field values of records of a table sequence.

Syntax：

T.record(A,k)

Note：

From the specified record k, reassign values to the fields of table sequence T’s records in sequence with members of sequence A. The number of to-be-reassigned records is determined by the number of both A’s members and T’s fields. If the number of A’s members is indivisible by the number of T’s fields, go on to reassign A’s remaining members to the fields of the next record.

Parameters：

An integer; this means the records will be modified from the kth one

By default or when k ==0, append records to table sequence T

A sequence whose members are used to reassign values to T’s fields

A table sequence

Options：

@i	Insert one or more records before the specified record k
@n	Return the newly-inserted or -modified records or record sequences

Return value：

The modified table sequence T

Example：

	A
1	=create(StuID,StuName,English)
2	=A1.record([1,"Lucy",98,2,"Petter",87])
3	=A1.record([10," Claire",88],0)	Append records to the table sequence when k=0
4	=A1.record([10,"Gail",88],3)	Modify the 3^rd record when k=3
5	=A1.record@i([11," Jamie",90],1)
6	=A1.record([3," Lily",67,4])
7	=A1.record@n([15,"Gail",88],3)	Return the newly-inserted record

r.record()[1145][1146]

Description：

Modify field values of a record with members of a sequence.

Syntax：

r.record(A)

Note：

The function uses members of sequence A to modify the fields of record r. If the number of A’s members is more than that of r’s fields, discard the surplus members; if the former is lessr than the latter, keep the orginal values of the remaining fields.

Parameters：

r	A record
A	A sequence

Return value:

A record

Example：

	A
1	=demo.query("select * from SCORES")	The original table sequence in A1
2	=A1(1)
3	[Class four,1,English,100]
4	=A2.record(A3)	A1’s table sequence after the first record is modified

redis()[1147][1148]

Description:

Connect to a Redis database under the single machine model.

Syntax:

redis(hostAndPort,password,connectionTimeout,soTimeout)

Note:

This external library function connects to a Redis database under the single machine model.

Parameters:

hostAndPort	The Redis database’s IP and port number, which is a string in the format of ip:port.
password	The Redis database’s authentication password.
connectionTimeout	Timeout value when trying to connect to the database (in seconds).
soTimeout	Timeout value when trying to read data(in seconds).

Return value:

Cursor

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis("192.168.18.131:6379","runqian",20,60)

redis_close()[1149][1150]

Description:

Close a Redis database connection.

Syntax:

redis_close(con)

Note:

This external library function disconnects from a Redis database.

Parameters:

con

Database connection string

Return value:

No return value

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_close(A1)

Related functions:

redis_cluster()[1151][1152]

Description:

Connect to Redis Cluster.

Syntax:

redis_cluster(hostAndPort[;hostAndPort1;hostAndPort;...],password,[connectionTimeout,soTimeout,maxRedirections;poolConfig])

Note:

External library function. The Redis Cluster connection doesn’t support redis_keys() function.

The parameter poolConfig involves the following values:

1. testOnReturn(boolean) #Whether connection objects will be validated before being returned.

2. blockWhenExhausted(boolean) #Whether to block when the connection is exhausted; default is true which blocks until timeout; a false value throws an exception.

3. evictionPolicyClassName(String) #Set the name of the eviction policy class name; default is DefaultEvictionPolicy (implement the eviction policy when the connection time exceeds the maximum idle time or the number of connections is greater than the maximum number of idle connections).

4. jmxEnabled(boolean) #Whether to enable JMX functionality; default is true.

5. jmxNamePrefix(String) #Set the MBean name, which is "pool" by default.

6. lifo(boolean) #Whether to use the last-in-first-out order; default is true.

7. maxWaitMillis(long) #Set the maximum amount of time (in miliseconds) before an exeption is thrown (BlockWhenExhausted needs to be true); with value set to be less than 0, block until the connection is established; default is -1.

8. minEvictableIdleTimeMillis(long) #Set the minimum amount of time that a connection can be idle before being tested for eviction; default is 1800000 milliseconds (30 minutes).

9. numTestsPerEvictionRun(int) #Set the maximum number of connections to test during idle eviction runs; a negative value is 1/abs(n); defaut is 3.

10. softMinEvictableIdleTimeMillis(long) #Set the minimum amount of time an object may sit idle before it is eligible for eviction; enable an eviction when idle time > this value & number of idle connections > number of idle connections, without referencing the value of minEvictableIdleTimeMillis (which is the default eviction policy).

11. testOnBorrow(boolean) #Whether connection objects borrowed from the pool will be validated before being returned; default is true.

12. testWhileIdle(boolean) #Return whether object sitting idle in the pool will be validated; default is false.

13. timeBetweenEvictionRunsMillis(long) #Set the amount of time (in miliseconds) between runs of the idle object evictor threads; won’t run the evictor threads if the value is negative; default is -1.

Parameters:

hostAndPort	The Redis database’s IP and port number, which is a string in the format of ip:port.
password	The Redis database’s authentication password.
connectionTimeout	Timeout value when trying to connect to the database (in seconds); can be omitted.
soTimeout	Timeout value when trying to read data(in seconds); can be omitted.
maxRedirections	The maximum number of allowed redirections; can be omitted.
poolConfig	Connection property configuration, which is a string in the format of “key:value[,key1:value1,…]”; can be omitted.

Return value:

Cursor

Example:

	A
1	=redis_cluster("192.168.0.76:6379";"192.168.0.76:6380","test1234",,10;JmxEnabled:true)

redis_get()[1153][1154]

Description:

Get the values of all the given keys.

Syntax:

redis_get(con,key[,key1,key2,…])

Note:

This external library function supports getting values of multiple keys.

Parameters:

con	Database connection string
key	Key name

Return value:

String

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_get(A1,"name")
3	=redis_get(A1,"id","name","age")

Related functions:

redis_getrange()[1155][1156]

Description:

Get a substring of the string stored at a key.

Syntax:

redis_getrange(con,key,start,end)

Note:

External library funcition. The length of the substring is determined by the two offset parameters start and end inclusive. Zero represents the first character of the string. A negative offset value counts from the end of the string. For instance, -1 represents the last character, -2 is the second-to-last character, and so on.

Parameters:

con	Database connection string
key	Key name
start	The beginning of the substring
end	The end of the substring

Return value:

A substring of the specified string

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_getrange(A1,"name",0,7)
3	=redis_getrange(A1,"name",-3,-1)

Related functions:

redis_hkeys()[1157][1158]

Description:

Get all the fields in a hash.

Syntax:

redis_hkeys(con,tbl)

Note:

This external library function won’t return a table of fields if the key doesn’t exist.

Parameters:

con	Database connection string
tbl	Hash table name

Return value:

A table containing all fields in the hash.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_hkeys(A1,"website")

redis_hlen()[1159][1160]

Description:

Get the number of fields in a hash.

Syntax:

redis_hlen(con,tbl)

Note:

This external library function returns zero if the key doensn’t exist.

Parameters:

con	Database connection string
tbl	Hash table name

Return value:

The number of fields in the hash.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_hlen(A1,"da")
3	=redis_hlen(A1,"db")

Related functions:

redis_hmget()[1161][1162]

Description:

Get the values of all the given hash fields.

Syntax:

redis_hmget(con,tbl,field[,field1,field2,....)

Note:

External library function. The order of the returned values is consistent with that of the given hash fields; if a given hash field doesn’t exist, return an empty string.

Parameters:

con	Database connection string
tbl	Hash table name
field	Field name

Return value:

A table containing all the given hash field values.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_hmget(A1,"pet","dog")
3	=redis_hmget(A1,"pet","dog","cat","aa")

Related functions:

redis_hvals()[1163][1164]

Description:

Get the values of all hash fields.

Syntax:

redis_hvals(con,tbl)

Note:

This external library function won’t return the table of hash field values if the key doesn’t exist.

Parameters:

con	Database connection string
tbl	Hash table name

Return value:

A table containing all hash key values.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	= redis_hvals(A1,"website")

Related functions:

redis_keys()[1165][1166]

Description:

Find all keys matching the specified pattern.

Syntax:

redis_keys(con,pattern)

Note:

This external library function finds all keys matching the given pattern.

Parameters:

con	Database connection string
pattern	A matching string

Return value:

A list of keys matching the given pattern.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	*=redis_keys(A1,"")**
3	=redis_keys(A1,"?b")
4	*=redis_keys(A1,"b")**
5	*=redis_keys(A1,"a[g]")**

redis_lindex()[1167][1168]

Description:

Get a member from a list by its index.

Syntax:

redis_lindex(con,key,index)

Note:

External library function. The parameter index representing an index starts from 0. That is to say, 0 represents the first member in the list, 1 the second member, and so on. The indexes can also be negative. -1 represents the last member in the list, -2 the second-to-last member, and so on. If the index value is beyond the range of the indexes of the list members, the function returns an empty value. If the data type of the parameter key isn’t list, an error will be reported.

Parameters:

con	Database connection string
key	List name
index	Index

Return value:

The list members whose indexes are the parmeter index.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	=redis_lindex(A1,"mylist",0)
3	=redis_lindex(A1,"mylist",1)
4	=redis_lindex(A1,"mylist",2)
5	=redis_lindex(A1,"mylist",-1)

redis_llen()[1169][1170]

Description:

Get the length of a list.

Syntax:

redis_llen(con,key)

Note:

External library function. If the parameter key isn’t supplied, the function will interpret it as an empty list and return 0. If the data type of the parameter key isn’t list, an error will be reported.

Parameters:

con	Database connection string
key	List name

Return value:

The length of the list.

Example:

	A
1	=redis("192.168.18.131:6379","runqian")
2	= redis_llen(A1,"abc")
3	= redis_llen(A1,"mylist")

Related functions: