[
https://issues.apache.org/jira/browse/CALCITE-4015?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Rui Wang updated CALCITE-4015:
------------------------------
Fix Version/s: 1.26.0
> Pass through parent collation request on subset or superset of join keys for
> EnumerableMergeJoin
> ------------------------------------------------------------------------------------------------
>
> Key: CALCITE-4015
> URL: https://issues.apache.org/jira/browse/CALCITE-4015
> Project: Calcite
> Issue Type: Improvement
> Components: core
> Reporter: Haisheng Yuan
> Assignee: Rui Wang
> Priority: Major
> Labels: pull-request-available
> Fix For: 1.26.0
>
> Time Spent: 7h 50m
> Remaining Estimate: 0h
>
> Pass through parent collation request on subset or superset of join keys for
> EnumerableMergeJoin.
> e.g.
> {code:java}
> select * from foo join bar on foo.a=bar.a and foo.b=bar.b order by foo.b;
> {code}
> collation on b is passed to mergejoin, mergejoin should generate an
> alternative with collation on b, a.
> {code:java}
> select * from foo join bar on foo.a=bar.a and foo.b=bar.b order by foo.a,
> foo.b, foo.c;
> {code}
> collation on a,b,c is passed to mergejoin, mergejoin should generate an
> alternative with collation on a,b,c, even the join keys are a,b, but since
> foo.c is also the output column, mergejoin can still request its child foo to
> deliver collation on a,b,c. The join keys must be the collation request's
> prefixes (keys order is not required to be reserved).
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
