diff options
Diffstat (limited to 'src/backend/optimizer/path/indxpath.c')
| -rw-r--r-- | src/backend/optimizer/path/indxpath.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c index 6e2051efc65..a43ca16d683 100644 --- a/src/backend/optimizer/path/indxpath.c +++ b/src/backend/optimizer/path/indxpath.c @@ -4163,6 +4163,22 @@ relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel, List *restrictlist, List *exprlist, List *oprlist) { + return relation_has_unique_index_ext(root, rel, restrictlist, + exprlist, oprlist, NULL); +} + +/* + * relation_has_unique_index_ext + * Same as relation_has_unique_index_for(), but supports extra_clauses + * parameter. If extra_clauses isn't NULL, return baserestrictinfo clauses + * which were used to derive uniqueness. + */ +bool +relation_has_unique_index_ext(PlannerInfo *root, RelOptInfo *rel, + List *restrictlist, + List *exprlist, List *oprlist, + List **extra_clauses) +{ ListCell *ic; Assert(list_length(exprlist) == list_length(oprlist)); @@ -4217,6 +4233,7 @@ relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel, { IndexOptInfo *ind = (IndexOptInfo *) lfirst(ic); int c; + List *exprs = NIL; /* * If the index is not unique, or not immediately enforced, or if it's @@ -4268,6 +4285,24 @@ relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel, if (match_index_to_operand(rexpr, c, ind)) { matched = true; /* column is unique */ + + if (bms_membership(rinfo->clause_relids) == BMS_SINGLETON) + { + MemoryContext oldMemCtx = + MemoryContextSwitchTo(root->planner_cxt); + + /* + * Add filter clause into a list allowing caller to + * know if uniqueness have made not only by join + * clauses. + */ + Assert(bms_is_empty(rinfo->left_relids) || + bms_is_empty(rinfo->right_relids)); + if (extra_clauses) + exprs = lappend(exprs, rinfo); + MemoryContextSwitchTo(oldMemCtx); + } + break; } } @@ -4310,7 +4345,11 @@ relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel, /* Matched all key columns of this index? */ if (c == ind->nkeycolumns) + { + if (extra_clauses) + *extra_clauses = exprs; return true; + } } return false; |