[
https://issues.apache.org/jira/browse/CALCITE-2582?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16622337#comment-16622337
]
Stamatis Zampetakis commented on CALCITE-2582:
----------------------------------------------
When pushing the filter condition through the projection a new condition is
generated so even if the initial condition was simplified the new condition may
not be. Apparently, this is what happens with some tests in sub-query.iq.
On the other hand, when we are not copying the filter and use the
relBuilder.filter, the new condition is always passing by the simplifier. So if
we are simplifying in this case why not simplifying in the previous also?
> FilterProjectTransposeRule does not always simplify the new filter condition
> ----------------------------------------------------------------------------
>
> Key: CALCITE-2582
> URL: https://issues.apache.org/jira/browse/CALCITE-2582
> Project: Calcite
> Issue Type: Improvement
> Components: core
> Affects Versions: 1.17.0
> Reporter: Stamatis Zampetakis
> Assignee: Julian Hyde
> Priority: Minor
> Fix For: 1.18.0
>
>
> After pushing the filter below the project a new condition is going to be
> generated along with a new Filter operator. The new condition is not going to
> be simplified if the filter operator is copied and not created using the
> RelBuilder.
> Thus the resulting plan may contain redundant conditions which can have a
> slight impact on performance. Apart, from that tests verifying the resulting
> (logical/physical) plan may produce indeterministic results if the rule is
> applied with (a different order and in combination with other rules).
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
