cs.groupx()

Read(291) Label: cluster cursor, records, group,

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

Parameters:

cs

A cluster cursor

x

Grouping expression

F

Resulting field name

y

An aggregate function on cs, which only supports sum/count/max/min/top/avg/iterate; when the function works with iterate(x,a;Gi,…) function, the latter’s parameter Gi should be omitted

G

Aggregate field name

n

Number of buffer rows; if the number of groups reaches n, write the grouping result to a temporary file; its value is n times of the default, which is automatically calculated, if n<1

Return value:

A cluster cursor

Example:

 

 

A

 

1

[192.168.31.72:8281, 192.168.31.72:8291]

 

2

=file("orderpart.ctx":[1], A1)

Open a cluster file

3

=A2. open ()

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()

 

10

=A7.groupx(if(EID<=10):ID;count(~):IdCount;2)

Since the number of groups reaches 2, write the grouping result to a temporary file