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Haisheng Yuan resolved CALCITE-1172. ------------------------------------ Resolution: Fixed Fix Version/s: 1.20.0 Pushed to master, thanks for the review, [~vgarg], [~zhztheplayer]! > Add rule to flatten two Aggregate operators into one > ---------------------------------------------------- > > Key: CALCITE-1172 > URL: https://issues.apache.org/jira/browse/CALCITE-1172 > Project: Calcite > Issue Type: Bug > Reporter: Julian Hyde > Priority: Major > Labels: pull-request-available > Fix For: 1.20.0 > > Time Spent: 3h 50m > Remaining Estimate: 0h > > If there is an Aggregate on top of an Aggregate, and the top aggregate's > group key is a subset of the lower aggregate's group key, and the aggregates > are expansions of rollups, then a rule would convert into a single aggregate. > For example, SUM of SUM becomes SUM; SUM of COUNT becomes COUNT; MAX of MAX > becomes MAX; MIN of MIN becomes MIN. AVG of AVG would not match, nor would > COUNT of COUNT. > The rule would convert > {noformat} > Aggregate({x}, SUM(c1), MIN(c2), MAX(c3)) > Aggregate({x, y}, SUM(c1), MIN(c2), MAX(c3)) > R > {noformat} > into > {noformat} > Aggregate({x}, SUM(c1), MIN(c2), MAX(c3)) > R > {noformat} > The rule would not work if there was anything between the two {{Aggregate}} > operators. > The implementation would use {{SqlSplittableAggFunction}} to deduce rollups, > and in fact would be practically the converse of > {{AggregateExchangeTransposeRule}} proposed in CALCITE-907. -- This message was sent by Atlassian JIRA (v7.6.3#76005)