Details
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New Feature
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Status: Closed
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Major
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Resolution: Fixed
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None
Description
Following approach similar to http://db.cs.berkeley.edu/jmh/miscpapers/sigmod93.pdf .
To reorder predicates in AND conditions, we could rank each of elements in the clauses in increasing order based on following formula:
rank = (selectivity - 1) / cost per tuple
Similarly, for OR conditions:
rank = (-selectivity) / cost per tuple
Selectivity can be computed with FilterSelectivityEstimator. For cost per tuple, we will need to come up with some heuristic based on how expensive is the evaluation of the functions contained in that predicate. Custom UDFs could be annotated.
Attachments
Attachments
Issue Links
- Is contained by
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HIVE-26751 Bug Fixes and Improvements for 3.2.0 release
- Open
- is related to
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HIVE-21867 Sort semijoin conditions to accelerate query processing
- Closed
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HIVE-26238 Decouple sort filter predicates optimization from digest normalization in CBO
- Closed
- links to