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| author | Simon Riggs <simon@2ndQuadrant.com> | 2018-03-27 19:57:02 +0100 |
|---|---|---|
| committer | Simon Riggs <simon@2ndQuadrant.com> | 2018-03-27 19:57:02 +0100 |
| commit | c203d6cf81b4d7e43edb2b75ec1b741ba48e04e0 (patch) | |
| tree | cf9e4a14290ef99232a5f5f477d5b2672df57629 /src/backend/executor/execMain.c | |
| parent | 1944cdc98273dbb8439ad9b387ca2858531afcf0 (diff) | |
| download | postgresql-c203d6cf81b4d7e43edb2b75ec1b741ba48e04e0.tar.gz postgresql-c203d6cf81b4d7e43edb2b75ec1b741ba48e04e0.zip | |
Allow HOT updates for some expression indexes
If the value of an index expression is unchanged after UPDATE,
allow HOT updates where previously we disallowed them, giving
a significant performance boost in those cases.
Particularly useful for indexes such as JSON->>field where the
JSON value changes but the indexed value does not.
Submitted as "surjective indexes" patch, now enabled by use
of new "recheck_on_update" parameter.
Author: Konstantin Knizhnik
Reviewer: Simon Riggs, with much wordsmithing and some cleanup
Diffstat (limited to 'src/backend/executor/execMain.c')
0 files changed, 0 insertions, 0 deletions