diff options
Diffstat (limited to 'src/backend/optimizer/util/plancat.c')
| -rw-r--r-- | src/backend/optimizer/util/plancat.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index bb809522424..de629e93c9a 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -324,6 +324,7 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent, info->predOK = false; /* set later in indxpath.c */ info->unique = index->indisunique; + info->immediate = index->indimmediate; info->hypothetical = false; /* @@ -1076,6 +1077,11 @@ join_selectivity(PlannerInfo *root, * Detect whether there is a unique index on the specified attribute * of the specified relation, thus allowing us to conclude that all * the (non-null) values of the attribute are distinct. + * + * This function does not check the index's indimmediate property, which + * means that uniqueness may transiently fail to hold intra-transaction. + * That's appropriate when we are making statistical estimates, but beware + * of using this for any correctness proofs. */ bool has_unique_index(RelOptInfo *rel, AttrNumber attno) |