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Haisheng Yuan commented on CALCITE-4018: ---------------------------------------- Not all, but N, produce at most N collations (where N is the number of columns). > Implement trait propagation for EnumerableValues > ------------------------------------------------- > > Key: CALCITE-4018 > URL: https://issues.apache.org/jira/browse/CALCITE-4018 > Project: Calcite > Issue Type: Improvement > Components: core > Reporter: Haisheng Yuan > Priority: Major > > Only passThrough is needed. > Currently, when Values is created, it will enumerate all the possible > collations no matter parent operator requires it or not, it will be a > disaster if the Values has thousands of columns, and the parent operator may > be just a hash aggregate or hashjoin, which doesn't care about its collation. > The collation should be created on demand by calling passThrough. -- This message was sent by Atlassian Jira (v8.3.4#803005)