Description:
Generate preaggregation file for a composite table/multizone composite table.
Syntax:
T.cuboid(f,Fi,…;y,…)
Note:
The function generates preaggregation file f for composite table/multizone composite table T. The preaggregation file will not update itself accordingly when the composite table is updated.
Parameter:
T |
A composite table/multizone composite table |
f |
Preaggregation file object |
Fi |
Grouping field |
y |
Aggregate expression; aggregate functions supported are sum/count/avg/max/min/top |
Return value:
Preaggregation file name
Example:
|
A |
|
1 |
=file("empcub.ctx") |
|
2 |
=A1.create@y(#EID,NAME,GENDER,DEPT,SALARY,BIRTHDAY) |
Create a composite table file. |
3 |
=demo.cursor("select EID,NAME,GENDER,DEPT,SALARY,BIRTHDAY from employee ") |
Return a table sequence:
|
4 |
=A2.append(A3) |
Append table sequence A3’s data to the composite table. |
5 |
=file("cub1") |
Preaggregation file object. |
6 |
=A2.cuboid(A5,DEPT,GENDER;avg(age(BIRTHDAY)),count(EID)) |
Generate preaggregation file cub1 for the composite table file, where DEPT and GENDER are grouping fields, and compute average age and find the number of employees in each group. |
7 |
=A2.cgroups(DEPT,GENDER;avg(age(BIRTHDAY)):AvgAge,count(EID):IdNum;;A5) |
Use the preaggregation file to perform grouping & aggregation on the composite table and return following result:
|