cursor()

dfx

Cellset file name

…

dfx’s parameter

@c

The dfx can be represented by a cell that corresponds to a subroutine defined by func() function

A

B

1

for arg1

2

=connect("demo").query("select * from GYMNASTICSWOMEN where ID=?",A1)

3

=B2.derive(avg(VAULT,UNEVENBARS,BALANCEBEAM,FLOOR):Average)

4

return B3

Perform a loop computation and return the result sets.

A

1

=[5,10,20,25]

2

=cursor("test.dfx",A1)

Cll test.dfx, pass A1’s sequence as the value of parameter arg1, and return result as a cursor.

3

=A2.fetch()

Fetch records from the cursor; the result is the union of returned result sets by the loop computation of test.dfx.

4

=call("test.dfx",A1)

Use call function to call test.dfx but only the result set of the first loop is returned. 

A

B

1

func

2

return A1.sum()

3

=cursor@c(A1,[2,5,7])

Call the code block whose master cell is A1.

4

=A3.fetch()

14.

cs

A cursor

…

A code block

A

B

1

=to(100000).new(rand(1000):f1,rand(1000):f2).cursor()

Generate a cursor.

2

cursor A1

=A2.groups(f1:count(1))

Traverse cursor A1, calculate A2’s channel in B2’s code block and write the result to A2.

3

cursor

=A3.groups(f2:count(1))

Same as the above.

A

A sequence

k

Segment number

n

The number of data segments; retrieve all data out when both k and n are omitted

@p

Assume data is ordered by the first field and the division won’t put records having same first field to different segments

A

1

=demo.query("select * from SCORES")

Return a sequence.

2

=A1.cursor(1:3)

Generate a cursor using A1’s sequence, divide the cursor into three segments, and retrieve the 1^st segment to return.

3

=A1.cursor()

Generate a cursor using A1’s sequence; return all data of the cursor when parameters are absent.

4

=demo.query("select  CLASS,STUDENTID,SUBJECT,SCORE from SCORES").sort(CLASS)

Return a sequence ordered by the 1^st field.

5

=A4.cursor@p(1:3)

With @p option, put records having same Class value in one segment, during which records are not allocated strictly according to parameters k and n.

A

A sequence

n

Number of subcursors; by default the value is【Default subcursor count in a multicursor】configured in the designer; when integrating esProc in a third-party application, its default value is cursorParallelNum value configured in raqsoftConfig.xml file

@p

Assume the sequence is ordered by the 1^st field and records having same 1^st field value won’t be put into two segments

A

1

=demo.query("select  CLASS,STUDENTID,SUBJECT,SCORE  from SCORES")

Return a sequence.

2

=A1.cursor@m()

Generate a multicursor from A1’s sequence; as parameters are absent, use value of【Default subcursor count in a multicursor】as the default number of subcursors.

3

=demo.query("select  CLASS,STUDENTID,SUBJECT,SCORE  from SCORES").sort(CLASS)

Return a sequence ordered by the 1^st field.

4

=A1.cursor@mp(3)

Generate a multicursor having three subcursors; with @p option, the segmentation won’t put records having same CLASS value in two segments.

A

An ordered sequence

mcs

A multicursor

K

A’s segmentation key

K’

mcs’s segmentation key

@p

Ignore parameters K and K’ and divide ordered sequence A by comparing and matching the first fields of mcs and A

A

1

=to(10000).new(#:c1,rand():c2).sort(c1)

Generate a sequence.

2

=A1.cursor@m(3)

Generate a multicursor having three subcursors from A1’s table sequence.

3

=to(10000).new(#:k1,rand(10000):k2,rand()*1000:k3).sort(k1)

Generate a table sequence ordered by k1.

4

=A3.cursor@m(A2,k1:c1)

Generate a multicursor segmented synchronously as A2’s multicursor, whose segmentation key is c1, based on A3’s table sequence, whose segmentation key is k1.

5

=A3.cursor@mp(A2)

Generate a multicursor segmented synchronously as A2’s multicursorbased on A3’s table sequence; as @p option is present, perform the segmentation by comparing and matching the first fields of A3 and A2, and in this case segmentation key parameters are not needed in the expression.

CS

A sequence of cursors.

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"])

The three parallel node servers return three cursors to form a sequence.

2

=A1.cursor()

Generate a multicursor using A1’s sequence of cursors.

3

=A2.fetch()

Fetch all records from A2’s multicursor.

cs

A unicursor.

n

The number of subcursors, whose default value is 【Default Number of Subcursors in a Multicursor】configured in the designer. When esProc is integrated into a third-party application, the default number of subcursors is cursorParallelNum value set up in raqsoftConfig.xml.

When n =0, the function generates a unicursor from which data is fetched parallelly.

A

1

=demo.cursor("select * from EMPLOYEE")

2

=A1.cursor@m(3)

Generate a multicursor.

db

Database connection

sql

A SQL query statement

args

Parameters passed to SQL, which can be values or names defined; separate multiple parameters with comma

@i

If the result set has only one column, the content of the returned cursor is a sequence

@d

Convert the numeric data type to the double data type, instead of the decimal data type

@x

Disconnect from the database automatically when the cursor is closed; this option applies to connect -mode database connection only; with this option, the cursor the function returns is irreversible

@v

Generate a cursor of pure table sequence or pure sequence

A

1

=demo.cursor("select * from SCORES")

Parameter db is data source name; this requires that demo data source is already connected.

2

=connect("demo")

3

=A2.cursor@x("select * from SCORES").fetch()

With connect-mode database connection, @x is used.

4

=A2.cursor("select * from STUDENTS")

Error is reported: Data Source demo is shutdown or wrong setup., which prompts you that data source isn’t started as database is automatically disconnected when A3’s cursor is closed.

A

1

>arg2="R&D"

Define parameter name as arg2 and parameter value as "R&D".

2

=demo.cursor("select EID,NAME,DEPT,GENDER from employee  where  EID<? and DEPT=?  and  GENDER=?",arg1,arg2,"M")

Query employee table, where arg1 is a cellset parameter whose value is 100 and arg2 is a parameter defined in A1, and the 3^rd parameter receives value “M” directly.

3

=A2.fetch()

Fetch data from A2’s cursor.

A

1

=demo.cursor("select NAME from  STUDENTS")

Query NAME field of STUDENTS table from demo data source and return a cursor whose content is as follows:

2

=demo.cursor@i("select  NAME from  STUDENTS")

When the result set contains only one column, use @i option to return content of the cursor as a sequence.

3

=demo.cursor@v("select * from  STUDENTS")

Return a cursor of pure table sequence.

4

=demo.cursor@iv("select  NAME from  STUDENTS")

Return a cursor of pure sequence.

5

=mysql.cursor@d("select * from ta")

As @d option is present, numeric data is converted to double type.

f

File object, only supporting the textual file object

F_i

Fields to be retrieved; all fields will be retrieved by default. The to-be-retrieved field(s) can be represented by their sequence numbers headed by the sign #

type

Field types, including bool, int, long, float, decimal, string, date, time and datetime. Data type of the first row will be used by default

s

User-defined separator. The default 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

@t

Use the first row of f as the field names. If omitted, use_1,_2,… as the default field names

@b

Retrieve data from a binary file written in the method of export, with the support of parameters F_i, k and n, and without support of parameters type and s. Ignore options @t, @s, @i, @q, @a, @n, @k, @p, @f, @l, @m, @c, @o, @d, @v and @r. The segmental retrieval could result in empty segment in cases when a file has only a very small number of records

@e

Make the function return null when F_i doesn’t exist in the file; raise an error when the option is absent 

@x

Delete the source file automatically on closing the cursor; the cursor that the function returns is irreversible when this option works

@s

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, the content of the returned cursor will be a sequence.

@q

Remove the quotation marks, if any, from both ends of data items, including the field names, and handle escape sequences; but will keep quotation marks within the data item

@c

Use comma as the separator when parameter s is absent

@m

With the option, the f.cursor@m(Fi:type,…;n,s) function returns a multicursor;  here parameter n is the number of segments; use the value of 【Default subcursor count in a multicursor】defined in the designer as the number subcursors if the option is absent; when integrating esProc into a third-party application, use cursorParallelNum value configured in raqsoftConfig.xml file as the default

@o

Use quotation marks as the escape character

@k

Retain white spaces on both sides of the data item; without it white spaces on both ends will be automatically deleted

@d

Delete a record if it contains unmatching data types or data formats and start examining data by type, or if the parentheses and the quotation marks in it do not match when @p option and @q option respectively are present

@n

Ignore and discard rows whose number of columns don’t match the first row

@v

Throw an exception, terminate the execution and output the content of the problem record when errors appear in @d check and @n check

@w

Read each row, including the column headers row, as a sequence and return a cursor of sequence made up of sequences

@a

Treat single quotes as what they are; left not handled by default , and can work with @q@p

@p

Enable handling the matching of parentheses (not including the separators within the parentheses) and quotes, as well as the escape sequences outside of the quotes

@f

Split the file content into a string by the separator without parsing

@l

Allow line continuation if there is an escape character \ at the end of the line

A

B

C

1

=file("D://Student.txt").cursor@tx()

Return the cursor for retrieving data, take the record in the first row as field names, and delete the file automatically when closing the cursor.

2

=create(CLASS,STUDENTID,SUBJECT,SCORE)

Construct a new table sequence.

3

for

4

if A3==1

=A1.skip(5)

If the loop number is 1, then skip 5 consecutive rows.

5

=A1.fetch(3)

Retrieve data from cursorA1, 3 rows each time.

6

if B5==null

Jump out from the loop when B5 is null.

7

Break

8

else

9

>A2.insert(0:B5,CLASS,STUDENTID,SUBJECT,SCORE)

Insert records in B5 into A2.

10

=file("D://Department.txt").cursor@t(Dept,Manager;,"/")

=A10.fetch()

Below is Department.txt:

Contents of Department. txt are separated with the slashes and read out according to the specified fields of DEPT and MANAGER.

11

=file("D://Department5.txt").cursor@t(;1:2)

=A11.fetch()

With F_i and s omitted, the function separates the cursor into 2 segments and retrieves the first one.

12

=file("D:// EMPLOYEE. btx").cursor@b(GENDER;1:2)

=A12.fetch()

Retrieve the GENDER field of the bin file, EMPLOYEE.btx(a segmented binary file) exported through f.export@z(); by default the exported binary file includes field names.

13

=file("D://EMPLOYEE.btx").cursor@b(;1:2)

=A13.fetch()

Retrieve the segmented binary file, EMPLOYEE1.btx, exported by f.export@b(), divide the file contents into 2 parts, and get the first part.

14

=file("D://Department.txt").cursor@ts()

= A14.fetch()

Won’t split fields, the cursor contains a table sequence consisting of a single string field.

15

=file("D://StuName.txt").cursor@i()

=A15.fetch()

StuName.txt is a file containing only one field, so the content of the cursor is a sequence.

16

=file("D://EMPLOYEE1.txt").cursor@tc()

=A16.fetch()

Retrieve the first segment of GENDER field of comma-seperated EMPLOYEE1.txt.

17

=file("D://Department3.txt").cursor@e(EID)

=A17.fetch()

Return null since EID field can’t be found in Department3.txt; without @e option, error will be reported, saying EID: field is not found.

18

=file("D://Department2.txt").cursor@tq(;,"|")

=A18.fetch()

Below is Department2.txt:  

B19’s result:

19

=file("D://Department.txt").cursor@tm(DEPT:string,MANAGER:int;3,"/")

The cursor is devided into 3 segments and the result of A19 is returned as a multicursor.

20

=file("D://Sale1.txt").cursor(#1,#3)

=A20.fetch()

Below is the Sale1.txt file:

Below is the result of B20:

21

=file("D:/Dep3.txt").cursor@cqo()

=A21.fetch()

Here is the Dep3.txt file:

With @o option, two double quotation marks are treated as one and return the result as follows:

22

=file("D:/Dep1.txt").cursor@k()

=A22.fetch()

Retain the whitespace characters on both sides of the data item.

23

=file("D:/Department1.txt").cursor@t(id:int,name;,"|")

=A23.fetch()

Return id and name fields of Department1.txt.

24

=file("D:/Department1.txt").cursor@td(id:int,name;,"|")

=A24.fetch()

Delete a record containing unmatching data types; rows where id value is a are deleted.

25

=file("D:/Department1.txt").cursor@tv(id:int,name;,"|")

=A25.fetch()

Verify data type matching, and, and if error reports, throw an exception, terminate the execution and output the content of the problem record; data type doesn’t match with rows where id value is a.

26

=file("D:/Dep2.txt").cursor@tdn(id:int,name,surname;,"|")

=A26.fetch()

Here’s the file Dep2.txt:

Ignore row 6 and row 8 because the number of columns doesn’t match that in row 1.

27

=file("D:/Desktop/DemoData/txt/City.txt").cursor@w()

=A27.fetch()

Use @w option to read each row as a sequence and return a cursor of sequence whose members are sequences.

28

=file("D://t1.txt").cursor@c()

=A28.fetch()

Below is t1.txt:

With @c option, use the comma as the default separator and return result as follows:

29

=file("D://t1.txt").cursor@cp()

=A29.fetch()

With @p option, parentheses and quotation marks matching will be handled during parsing.

30

=file("D://t1.txt").cursor@cpa()

=A30.fetch()

With @a option, single quotes are treated as quotes.

31

=file("D://t2.txt").cursor@l()

=A31.fetch()

Below is t2.txt:

With @1 option, allow line continuation when there is an escape character at the end of the line.

32

=file("D://t3.txt").cursor@f()

=A32.fetch()

With @f option, just splt the file as a string using the separator.

@m

The T.cursor@m(x:C…;wi,...;n) function with this option generates a multicursor segmented into n parts. n is an integer; the function returns an ordinary cursor if n<2; use the value of【Default number of subcursors in a multicursor】 set in【Tool】-【Options】if n is absent.

@v

Generate a pure table sequence-based columnwise cursor, which has higher performance than regular cursors.

@x

Automatically close the entity table/in-memory table after data in the cursor is fetched.

@g

When T is a multizone composite table and if group() operation will be executed on the result cursor, use this option to speed up the computation.

@w

Used on a multizone composite table with update mark;

Perform update merge; when zone tables share a same key value, ignore the record contained in the zone table with a smaller number; segmentation is performed according to the way zone table 1 is split;

Handle the update mark and do not return records with a deletion mark to the cursor; but if the key value of a record with the deletion mark is unique in the multizone composite table, just retain it;

This option enables retrieving key field(s) as well as the deletion mark field, if there is one, forcefully.

@z

Get data in the inverse order; do not support segmentation in this case.

T

An entity table or an in-memory table or a multizone composite table

x

Expression; by default, all fields of T will be returned to the cursor

C

Column alias; can be omitted

wi

Filtering condition; separate multiple conditions by comma(s) and their relationships are AND; besides regular filtering expressions, you can also use the following five types of syntax in a filtering condition, where K is a field in the entity table:

1．K=w

w usually uses expression T_i.find(K) or T_i.pfind(K), where T_i is a table sequence. When value of w is null or false, the corresponding record in the entity table will be filtered away; when w is expression T_i.find(K) and the to-be-selected fields C,... contain K, T_i’s referencing field will be assigned to K; when w is expression T_i.pfind(K) and the to-be-selected fields C,... contain K, sequence numbers of K values in T_i will be assigned to K.

2．(K₁=w₁,…K_i=w_i,w)

K_i=w_i is an assignment expression. Generally, parameter w_i can use expression T_i.find(K_i) or T_i.pfind(K), where T_i is a table sequence; when w_i is expression T_i.find(K) and the to-be-selected fields C,... contain K_i, T_i’s referencing field will be assigned to K_i correspondingly; when w_i is expression T_i.pfind(K_i) and the to-be-selected fields C,... contain K_i, sequence numbers of K_i values in T_i will be assigned to K_i.

w is a filter expression; you can reference K_i in w.

3．K:T_i

T_i is a table sequence. Compare K_i value in the entity table with key values of T_i and discard records whose K_i value does not match; when the to-be-selected fields C,... contain K, T_i’s referencing field will be assigned to K.

4．K:T_i:null

Filter away all records that satisfy K:T_i.

5．K:T_i:#

Locate records according to sequence numbers, compare sequence numbers of records in table sequence T_i according to the entity table’s K values, and discard non-matching records; when the to-be-selected fields C,... contain K, T_i’s referencing field will be assigned to K

k

A positive integer (k≤n) representing the k^th segment

n

A positive integer representing the number of segments; return all records when parameters k:n are absent

A

1

for 100

2

=to(10000).new(#:k1,rand():c1).sort@o(k1)

Return a table sequence:

3

=to(10000).new(#:k1,rand(10000):c2,rand()*1000:c3).sort@o(k1)

Return a table sequence:

4

=A2.cursor()

Return a cursor.

5

=A3.cursor()

Return a cursor.

6

=file("D:\\tb4.ctx")

Generate a composite table file.

7

=A6.create(#k1,c1)

Create A6’s base table whose key is k1.

8

=A7.append(A4)

Append data of A4’s cursor to A7’s base table.

9

=A7.attach(table4,c2,c3)

Create an attached table table4 for the base table.

10

=A9.append(A5)

Append data of A5’s cursor to attached table table4.

11

=A9.cursor(;c2<1000;2:3)

Divide records meeting c2<1000 in the attached table into 3 segments and return a cursor of all columns of the second segment.

12

=A11.fetch()

Fetch data from A11’s cursor.

13

=A7.cursor(;c1>0.99)

Get records meeting c1>0.99 from A7’s base table

14

=A13.fetch()

Fetch data from A13’s cursor.

b

15

=A9.cursor(k1,c1:b,c3;c3>999)

Get the base table’s k1 field and c1 field from attached table table4, as well as c3 field of the attached table, according to condition c3>999, and rename c1 b.

16

=A15.fetch()

Fetch data from A15’s cursor.

17

=A9.cursor@m(;;3)

Use @m option to generate a multicursor from attached table table4.

A

1

=file("employee1.ctx")

Generate composite table file employee1.ctx.

2

=A1.create@y(#EID,NAME,GENDER,SALARY)

Create the base table of composite table employee1.ctx, which contains columns EID, NAME, GENDER and SALARY and where EID is the dimension.

3

=connect("demo").cursor("select  EID,NAME,GENDER,SALARY  from  employee")

Return a cursor.

4

=A2.append@i(A3)

Append records of A3’s cursor to A2’s base table.

5

=A2.cursor@v(;SALARY>1000;)

Return a column-wise cursor, and automatically close A2’s composite table after data is fetched from it.

6

=A5.groups(GENDER;avg(SALARY):SALARY_AVG)

Perform grouping & aggregation operation on A5’s cursor.

7

=A2.cursor(;SALARY>2000)

Error is reported, prompting“Stream Closed” .

A

1

=100000.new(~:ID,rand(2):FM).cursor()

2

=file("nc.ctx":[1,2])

Generate a homo-names files group.

3

=A2.create@y(#ID,FM;if(FM==1,1,2))

Return a multizone composite table.

4

=A3.append@x(A1)

Append cursor A1’s data to the multizone composite table; below is content of the multizone composite table:

1.nc.ctx  2.nc.ctx

5

=A3.cursor(;;1:3)

Split the multizone composite table into three segments, return the first segment of each zone table, merge them and return result as a cursor:

Data in zone table 1 and that in zone table 2 has been merged by their dimensions.

A

1

=file("emp.ctx")

2

=A1.open()

Open the composite table file.

3

=A2.import()

As no parameters are present, return all data in the entity table.

4

=5.new(~:ID,~*~:Num).keys(ID)

Generate a table sequence using ID as the key.

5

=A2.cursor(EID,NAME;EID=A4.find(EID))

Use K=w filtering mode; in this case w is T_i.find(K) and entity table records making EID=A4.find(EID) get null or false are discarded; EID is the selected field, to which table sequence A4’s referencing field are assigned.

6

=A2.cursor(EID,NAME;EID=A4.pfind(EID))

Use K=w filtering mode; in this case w is T_i.pfind(K) and entity table records making EID=A4.pfind(EID) get null or false are discarded; EID is the selected field, to which its sequence numbers in table sequence A4 is assigned.

7

=A2.cursor(EID,NAME;EID:A4)

Use K:T_i filtering mode; compare the entity table’s EID values with the table sequence’s key values and discard entity table records that cannot match.

8

=A2.cursor(NAME,SALARY;EID:A4)

This is a case where K isn’t selected; EID isn’t the selected field, so only filtering is performed.

9

=A2.cursor(EID,NAME;EID:A4:null)

Use K:T_i:null filtering mode; compare the entity table’s EID values with the table sequence’s key values and discard entity table records that can match.

10

=A2.cursor(EID,NAME;EID:A4:#)

Use K:T_i:# filtering mode; compare with sequence numbers of table sequence’s records according to the entity table’s EID values, and discard records that cannot match.

11

=connect("demo").query("select top 2  NAME,GENDER  from employee").keys(NAME)

Return a table sequence using NAME as the key.

12

=A2.cursor(EID,NAME;(EID=A4.find(EID),NAME=A11.find(NAME),EID!=null&&NAME!=null))

Use (K₁=w₁,…K_i=w_i,w) filtring mode; return records that meet all conditions

A

1

=100000.new(~:ID,rand(2):FM)

2

=file("curz.ctx")

3

=A2.create@y(#ID,FM)

Create a composite table.

4

=A3.append@i(A1)

5

=A4.cursor().fetch()

Return the composite table as a cursor and fetch data from the cursor:

6

=A4.cursor@z().fetch()

Use @z option to get data in the inverse order and fetch data from the cursor as follows:

A

1

=connect("demo").cursor("select  EID,NAME,GENDER  from employee") 

2

=A1.derive(:Defiled)

3

=A2.new(EID,Defiled,NAME,GENDER)

Return a cursor whose content is as follows:

4

=file("ecd.ctx":[1,2])

Define a homo-name files group: 1.ecd.ctx and 2.ecd.ctx.

5

=A4.create@yd(#EID,Defiled,NAME,GENDER;if(GENDER=="F",1,2))

Create a multizone composite table, set EID as the key, use @d option to make Defiled field the update mark and put records where GENDER is F to 1.ed.ctx and the other records to 2.ed.ctx.

6

=A5.append@ix(A3)

Append cursor A3’s data to the multizone composite table.

7

=create(EID,Defiled,NAME,GENDER).record([0,true,,,1,true,,,

2,false,"BBB","F"])

Return a table sequence whose content is as follows:

8

=file("ecd.ctx":[3])

9

=A8.create@yd(#EID,Defiled,NAME,GENDER;3)

Add zone table 3.ecd.ctx and make Defiled the update mark field.

10

=A9.append@i(A7)

Append table sequence A7’s records to zone table 3.ecd.ctx.

11

=file("ecd.ctx":[1,2,3]).open()

Open composite table file ecd.ctx.

12

=A11.cursor().fetch()

Return all data in the multizone composite table ecd.ctx to the cursor; below is the returned content:

13

=A11.cursor@w().fetch()

With @w option, return data in multizone composite table ecd.ctx as a cursor and recognize the update mark:

Do not return the record whose EID value is 2 and where the update mark value is true (meaning to-be-deleted) to the cursor;

Update the record where EID value is 2 and marked by false (meaning to-be-modified);

Retain the record where EID value is 0, marked by true (meaning to-be-deleted), and whose key value is unique, and return it to the cursor; Below is content of the returned cursor:

@m

The function with this option generates a cluster multicursor synchronously segmented into n parts. n is a positive integer representing the number of segments to be divided; the function returns an ordinary cursor if n<2; use the value of【Default number of subcursors in a multicursor】set in【Tool】-【Options】if n is absent