https://issues.apache.org/jira/browse/CALCITE-853
On Fri, Aug 21, 2015 at 2:20 PM, Julian Hyde <[email protected]> wrote: > Yes, that would be useful. Please log a jira. > > Enumerable.groupBy doesn't know its input's collation so can't make that > decision, but EnumerableAggregate does. I think that EnumerableAggregate > should have a "trigger key", a subset of its group key, and if the trigger > key changes it will emit and flush its hash table. > > As well as for your use case, it will be useful for streaming queries. > > Julian > > > On Aug 20, 2015, at 2:35 AM, Li Yang <[email protected]> wrote: > > > > I encountered Out Of Mem exception when a huge result set is passed into > > EnumerableAggregate and get aggregated in memory. I'm thinking if the > input > > is sorted by the group-by key, then the groupBy() don't have to hold all > > data in memory any more. > > > > So does the Enumerable groupBy() take advantage of input collation > > currently? Should I open a JIRA for it? > > > > > > Cheers > > Yang > >
