Hi Vladimir, Looks like this message is for d...@calcite.apache.org, not dev@ignite.apache.org, or am I mistaken?
On Wed, May 19, 2021 at 2:25 PM Vladimir Ozerov <ppoze...@gmail.com> wrote: > Hi, > > The AggregateUnionTransposeRule attempts to push the Aggregate below the > Union. > > Before: > Aggregate[group=$0, agg=SUM($1] > Union[all] > Input1 > Input2 > > After: > Aggregate[group=$0, agg=SUM($1] > Union[all] > Aggregate[group=$0, agg=SUM($1] > Input1 > Aggregate[group=$0, agg=SUM($1] > Input2 > > When pushing the Aggregate, it checks whether the input is definitively > unique on the grouping key. If yes, the Aggregate is not installed on top > of the input, assuming that the result would be the same as without the > aggregate. This generates a type mismatch exception when aggregation is > pushed only to some of the inputs: > Aggregate[group=$0, agg=SUM($1] > Union[all] > Aggregate[group=$0, agg=SUM($1] > Input1 > Input2 > > It seems that the uniqueness check should not be in that rule at all, and > the aggregate should be pushed unconditionally. Motivation: we already have > AggregateRemoveRule that removes unnecessary aggregates. No need to > duplicate the same non-trivial logic twice. > > Does the proposal make sense to you? > > Regards, > Vladimir. >
