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author | Thomas Munro <tmunro@postgresql.org> | 2019-06-28 11:11:26 +1200 |
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committer | Thomas Munro <tmunro@postgresql.org> | 2019-06-28 17:18:06 +1200 |
commit | d7395cf608e7ec8c9cebd17c19dc5d07c761010e (patch) | |
tree | b685dd9a75abc92740af43c1fe87e71ec3c0d1b9 /src | |
parent | 88d63c6ac78de0a9c8bffc43146666e630efc426 (diff) | |
download | postgresql-d7395cf608e7ec8c9cebd17c19dc5d07c761010e.tar.gz postgresql-d7395cf608e7ec8c9cebd17c19dc5d07c761010e.zip |
Fix misleading comment in nodeIndexonlyscan.c.
The stated reason for acquiring predicate locks on heap pages hasn't
existed since commit c01262a8, so fix the comment. Perhaps in a later
release we'll also be able to change the code to use tuple locks.
Back-patch all the way.
Reviewed-by: Ashwin Agrawal
Discussion: https://postgr.es/m/CAEepm%3D2GK3FVdnt5V3d%2Bh9njWipCv_fNL%3DwjxyUhzsF%3D0PcbNg%40mail.gmail.com
Diffstat (limited to 'src')
-rw-r--r-- | src/backend/executor/nodeIndexonlyscan.c | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c index 9f54c4633e8..87c2656a54a 100644 --- a/src/backend/executor/nodeIndexonlyscan.c +++ b/src/backend/executor/nodeIndexonlyscan.c @@ -179,11 +179,8 @@ IndexOnlyNext(IndexOnlyScanState *node) errmsg("lossy distance functions are not supported in index-only scans"))); /* - * Predicate locks for index-only scans must be acquired at the page - * level when the heap is not accessed, since tuple-level predicate - * locks need the tuple's xmin value. If we had to visit the tuple - * anyway, then we already have the tuple-level lock and can skip the - * page lock. + * If we didn't access the heap, then we'll need to take a predicate + * lock explicitly, as if we had. For now we do that at page level. */ if (tuple == NULL) PredicateLockPage(scandesc->heapRelation, |