Outer join removal in citus_tables view#8546
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michailtoksovo wants to merge 1 commit intocitusdata:mainfrom
Open
Outer join removal in citus_tables view#8546michailtoksovo wants to merge 1 commit intocitusdata:mainfrom
michailtoksovo wants to merge 1 commit intocitusdata:mainfrom
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Codecov Report✅ All modified and coverable lines are covered by tests.
Additional details and impacted files@@ Coverage Diff @@
## main #8546 +/- ##
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- Coverage 88.88% 72.74% -16.15%
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Files 286 286
Lines 63763 63750 -13
Branches 8017 8012 -5
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- Hits 56678 46376 -10302
- Misses 4776 14621 +9845
- Partials 2309 2753 +444 🚀 New features to boost your workflow:
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Hey! I noticed a small issue with the
citus_tablesview: even when selecting just a single column from it (e.g.table_name), it still triggers network communication between nodes due tocitus_shard_size()call within a subquery. I wanted to get rid of that overhead wherever possible.I replaced the INNER JOIN with a LEFT OUTER JOIN. This lets PostgreSQL's outer join removal optimization kick in, so the join (and the extra network traffic) gets completely skipped when the right-side columns aren't used.