Pre-aggregate

Create index file for a composite table and then we use the Pre-aggregate functionality to group and summarize certain fields in advance in an effort to speed up computations on an upper-level function.

Click CTX -> Cube -> New to enter the following pre-aggregation window:

Name: The name of the pre-aggregated data cube.

Grouping Field: Set a grouping field by which data is grouped.

Aggregate Expression: Can be an aggregate function, which can be sum/count/avg/max/min/top. More details can be found in T.cuboid(f,F_i,~{!-~};y:G_i,~{!-~}) function.

Set grouping field and aggregate expression:

Click Execute to execute the pre-aggregation definition.

And then Yes to finish the pre-aggregation.

Click CTX -> Cube -> View Data to view the created pre-aggregation file.