Details
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Improvement
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Status: Closed
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Major
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Resolution: Fixed
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None
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None
Description
Currently such queries are written into group by + inner join with value generator and is inefficient. Value generator consists of join with outer query to fetch all correlated values. This value generator could be completely eliminated if such queries are instead rewritten into LEFT SEMI JOIN.
Note that to do this first hive need to support LEFT SEMI JOIN with non-equi condition (HIVE-17766).
Attachments
Attachments
Issue Links
- depends upon
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HIVE-17766 Support non-equi LEFT SEMI JOIN
- Closed
- links to