diff options
| author | Andres Freund | 2015-05-08 20:22:05 +0000 |
|---|---|---|
| committer | Andres Freund | 2015-05-08 20:28:23 +0000 |
| commit | bab64ef9e8bc56fa5db9bd41cefb54c3d8051dbe (patch) | |
| tree | d7286cb2add3c11f3854a846746f8a0474ba9f9a | |
| parent | de7688442f5aaa03da60416a6aa3474738718803 (diff) | |
Fix two problems in infer_arbiter_indexes().
The first is a pretty simple bug where a relcache entry is used after
the relation is closed. In this particular situation it does not appear
to have bad consequences unless compiled with RELCACHE_FORCE_RELEASE.
The second is that infer_arbiter_indexes() skipped indexes that aren't
yet valid according to indcheckxmin. That's not required here, because
uniqueness checks don't care about visibility according to an older
snapshot. While thats not really a bug, it makes things undesirably
non-deterministic. There is some hope that this explains a test failure
on buildfarm member jaguarundi.
Discussion: [email protected]
| -rw-r--r-- | src/backend/optimizer/util/plancat.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index 8bcc5064a37..894e0db802d 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -547,13 +547,11 @@ infer_arbiter_indexes(PlannerInfo *root) goto next; /* - * If the index is valid, but cannot yet be used, ignore it. See - * src/backend/access/heap/README.HOT for discussion. + * Note that we do not perform a check against indcheckxmin (like + * e.g. get_relation_info()) here to eliminate candidates, because + * uniqueness checking only cares about the most recently committed + * tuple versions. */ - if (idxForm->indcheckxmin && - !TransactionIdPrecedes(HeapTupleHeaderGetXmin(idxRel->rd_indextuple->t_data), - TransactionXmin)) - goto next; /* * Look for match on "ON constraint_name" variant, which may not be @@ -566,10 +564,10 @@ infer_arbiter_indexes(PlannerInfo *root) (errcode(ERRCODE_WRONG_OBJECT_TYPE), errmsg("ON CONFLICT DO UPDATE not supported with exclusion constraints"))); + candidates = lappend_oid(candidates, idxForm->indexrelid); list_free(indexList); index_close(idxRel, NoLock); heap_close(relation, NoLock); - candidates = lappend_oid(candidates, idxForm->indexrelid); return candidates; } else if (indexOidFromConstraint != InvalidOid) |