Using the Query Builder, users can optionally split the results of the aggregation function by the stored and virtual columns listed in the Compare field. We don't limit the number of comparison dimensions. The results are grouped by the combination of values encountered in the listed columns. Those combinations also control how many instances of the aggregator are used by the scan engines. Any columns listed here will get scanned during the query.
Scuba allows you to compare time ranges (OVER), measures (SHOW), filters (FOR). Another way to compare is split by (formerly group by in Scuba 2.x).