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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2017-09-17 15:28:51 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2017-09-17 15:28:51 -0400 |
| commit | 6f44fe7f121ac7c29c1ac8553e4e209f9c3bfbcb (patch) | |
| tree | 5489479a43a5f1fe55927183e81e6bfb53935195 /src | |
| parent | 27c6619e9c8ff80cd78c7f66443aa005734cda90 (diff) | |
| download | postgresql-6f44fe7f121ac7c29c1ac8553e4e209f9c3bfbcb.tar.gz postgresql-6f44fe7f121ac7c29c1ac8553e4e209f9c3bfbcb.zip | |
Allow rel_is_distinct_for() to look through RelabelType below OpExpr.
This lets it do the right thing for, eg, varchar columns.
Back-patch to 9.5 where this logic appeared.
David Rowley, per report from Kim Rose Carlsen
Discussion: https://postgr.es/m/VI1PR05MB17091F9A9876528055D6A827C76D0@VI1PR05MB1709.eurprd05.prod.outlook.com
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/optimizer/plan/analyzejoins.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/backend/optimizer/plan/analyzejoins.c b/src/backend/optimizer/plan/analyzejoins.c index 34317fe7782..511603b5810 100644 --- a/src/backend/optimizer/plan/analyzejoins.c +++ b/src/backend/optimizer/plan/analyzejoins.c @@ -704,6 +704,14 @@ rel_is_distinct_for(PlannerInfo *root, RelOptInfo *rel, List *clause_list) var = (Var *) get_leftop(rinfo->clause); /* + * We may ignore any RelabelType node above the operand. (There + * won't be more than one, since eval_const_expressions() has been + * applied already.) + */ + if (var && IsA(var, RelabelType)) + var = (Var *) ((RelabelType *) var)->arg; + + /* * If inner side isn't a Var referencing a subquery output column, * this clause doesn't help us. */ |