History

This feature improvement is avaliable after v3.1.0.

...

There were some use cases for this feature:

Case 1 Force choose the right

...

hit cube

In many OLAP team, we choose to build some smaller cubes other than SINGLE larger cube to reduce build duration/cube storage. For example, we build three small cubes: the first cube with three dimensions "ABC", the second cube with three dimensions "ADE", and the third cube with five dimensions “ADHGF", rather than a bigger cube with eight dimensions "ABCDEHGF". We can see, because of the removal of cuboid "ABCDEHGF", our design will reduce total storage a lot in theory (however it depends on specific use scenarios).

After that, the design we choose will cause new question. UserA create and build Cube1(with three dimensions A,B,C) from 2020-01-07 to 2020-01-10, and UserB create and build Cube2 (with four five dimensions A,D,H,G,F) from 2020.01.05 to 2020-01-10.

When UserB querying "select A,count(*) from db.table group by A; " , this query will hit Cube1 automatically(but UserB wanted result from want query hit Cube2), because of less dimension/measure. So that result from 01.05 to 01.07 will disappear. To fix this problem, we have to force choose Cube2 to answer this query.

...