Hi Julian
Thanks for your reply.
As you said, using
`org.apache.calcite.rel.metadata.RelMetadataQuery#getPulledUpPredicates` is
very effective.
I will log a jira later.
Best
Xurenhe
On 2022/03/07 20:30:45 Julian Hyde wrote:
> Sounds reasonable. Please log a jira.
>
> Consider implementing this rule by inspecting predicates or unique keys,
rather than by matching a Project or Filter. If you can ascertain that a
sort column has only one value (counting NULL as a value for these
purposes) then you can remove it from the sort.
>
> I find that using metadata in this way is very effective. You get the
desired effect without moving relational operators around.
>
> Julian
>
> > On Mar 7, 2022, at 1:01 AM, 徐仁和 <xu...@gmail.com> wrote:
> >
> > Hi community:
> >
> > Could calcite support the rule to pull up constant project from sort,
just
> > like `AggregateProjectPullUpConstantsRule`?
> >
> > -- sql
> > select pay_amount, pay_id, user_id
> > from pay_tbl
> > where pay_id = 1234
> > group by pay_amount, pay_id, user_id
> > order by pay_amount, pay_id, user_id
> >
> > -- origin rel tree
> > LogicalSort(sort0=[$0], sort1=[$1], sort2=[$2], dir0=[ASC], dir1=[ASC],
> > dir2=[ASC])
> > LogicalProject(pay_amount=[$0], pay_id=[1234], user_id=[$1])
> > LogicalAggregate(group=[{0, 1}])
> > LogicalProject(pay_amount=[$1], user_id=[$3])
> > LogicalFilter(condition=[=($0, 1234)])
> > LogicalTableScan(table=[[default, pay_tbl]])
> >
> > -- optimized rel tree
> > LogicalProject(pay_amount=[$0], pay_id=[1234], user_id=[$1])
> > LogicalSort(sort0=[$0], sort2=[$1], dir0=[ASC], dir2=[ASC])
> > LogicalProject(pay_amount=[$0], user_id=[$1])
> > LogicalAggregate(group=[{0, 1}])
> > LogicalProject(pay_amount=[$1], user_id=[$3])
> > LogicalFilter(condition=[=($0, 1234)])
> > LogicalTableScan(table=[[default, pay_tbl]])
>
