If I make an aggregation of attributes (x,y,z) is there any need to additionally add aggregations for (x,y),(x,z) and (y,z) to be fully preaggregated?
The reason I ask is because if not I would expect the processing to merge these 3 aggregations back into the overarching one in the MergeAggregates on Disk phase of processing. But judging from the size of the resulting cubes it keeps all 4 aggregates.
You have guessed right. If you were to design 3 aggregations, all 3 of them are going to get created. You aggregation design should be smart to eliminate unnecessary aggregations.
Edward.
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