HIVE-26160: Materialized View rewrite does not check tables scanned in sub-query expressions #3246
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What changes were proposed in this pull request?
Temporary apply the
HiveSubQueryRemoveRulebefore collecting tables scanned by the initial CBO plan when performing sql text based MV rewrite.Why are the changes needed?
For Materialized View rewrite based on exact sql text match Hive uses the initial CBO plan which may contains sub-query expressions but the algorithm traverse the plan and collects the tables can not handle sub-query expressions.
Does this PR introduce any user-facing change?
Yes. If a query plan was rewritten to scan an outdated MV the results can be different.
How was this patch tested?