diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/optimizer/prep/prepjointree.c | 4 | ||||
| -rw-r--r-- | src/backend/optimizer/util/clauses.c | 78 | ||||
| -rw-r--r-- | src/include/optimizer/clauses.h | 5 |
3 files changed, 70 insertions, 17 deletions
diff --git a/src/backend/optimizer/prep/prepjointree.c b/src/backend/optimizer/prep/prepjointree.c index 21bd8332f4a..1c73c57dadf 100644 --- a/src/backend/optimizer/prep/prepjointree.c +++ b/src/backend/optimizer/prep/prepjointree.c @@ -16,7 +16,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.55 2008/10/04 21:56:53 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/prep/prepjointree.c,v 1.56 2008/10/09 19:27:40 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -383,7 +383,7 @@ inline_set_returning_functions(PlannerInfo *root) Query *funcquery; /* Check safety of expansion, and expand if possible */ - funcquery = inline_set_returning_function(root, rte->funcexpr); + funcquery = inline_set_returning_function(root, rte); if (funcquery) { /* Successful expansion, replace the rtable entry */ diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c index bd0192d829e..14b9313a9aa 100644 --- a/src/backend/optimizer/util/clauses.c +++ b/src/backend/optimizer/util/clauses.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.268 2008/10/04 21:56:53 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.269 2008/10/09 19:27:40 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -111,6 +111,7 @@ static Query *substitute_actual_srf_parameters(Query *expr, int nargs, List *args); static Node *substitute_actual_srf_parameters_mutator(Node *node, substitute_actual_srf_parameters_context *context); +static bool tlist_matches_coltypelist(List *tlist, List *coltypelist); /***************************************************************************** @@ -3659,17 +3660,16 @@ evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod) * inline_set_returning_function * Attempt to "inline" a set-returning function in the FROM clause. * - * "node" is the expression from an RTE_FUNCTION rangetable entry. If it - * represents a call of a set-returning SQL function that can safely be - * inlined, expand the function and return the substitute Query structure. - * Otherwise, return NULL. + * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a + * set-returning SQL function that can safely be inlined, expand the function + * and return the substitute Query structure. Otherwise, return NULL. * * This has a good deal of similarity to inline_function(), but that's * for the non-set-returning case, and there are enough differences to * justify separate functions. */ Query * -inline_set_returning_function(PlannerInfo *root, Node *node) +inline_set_returning_function(PlannerInfo *root, RangeTblEntry *rte) { FuncExpr *fexpr; HeapTuple func_tuple; @@ -3686,6 +3686,8 @@ inline_set_returning_function(PlannerInfo *root, Node *node) Query *querytree; int i; + Assert(rte->rtekind == RTE_FUNCTION); + /* * It doesn't make a lot of sense for a SQL SRF to refer to itself * in its own FROM clause, since that must cause infinite recursion @@ -3695,9 +3697,9 @@ inline_set_returning_function(PlannerInfo *root, Node *node) check_stack_depth(); /* Fail if FROM item isn't a simple FuncExpr */ - if (node == NULL || !IsA(node, FuncExpr)) + fexpr = (FuncExpr *) rte->funcexpr; + if (fexpr == NULL || !IsA(fexpr, FuncExpr)) return NULL; - fexpr = (FuncExpr *) node; /* * The function must be declared to return a set, else inlining would @@ -3707,10 +3709,6 @@ inline_set_returning_function(PlannerInfo *root, Node *node) if (!fexpr->funcretset) return NULL; - /* Fail if function returns RECORD ... we don't have enough context */ - if (fexpr->funcresulttype == RECORDOID) - return NULL; - /* * Refuse to inline if the arguments contain any volatile functions or * sub-selects. Volatile functions are rejected because inlining may @@ -3837,10 +3835,21 @@ inline_set_returning_function(PlannerInfo *root, Node *node) if (!check_sql_fn_retval(fexpr->funcid, fexpr->funcresulttype, querytree_list, true, NULL) && - get_typtype(fexpr->funcresulttype) == TYPTYPE_COMPOSITE) + (get_typtype(fexpr->funcresulttype) == TYPTYPE_COMPOSITE || + fexpr->funcresulttype == RECORDOID)) goto fail; /* reject not-whole-tuple-result cases */ /* + * If it returns RECORD, we have to check against the column type list + * provided in the RTE; check_sql_fn_retval can't do that. (If no match, + * we just fail to inline, rather than complaining; see notes for + * tlist_matches_coltypelist.) + */ + if (fexpr->funcresulttype == RECORDOID && + !tlist_matches_coltypelist(querytree->targetList, rte->funccoltypes)) + goto fail; + + /* * Looks good --- substitute parameters into the query. */ querytree = substitute_actual_srf_parameters(querytree, @@ -3938,3 +3947,46 @@ substitute_actual_srf_parameters_mutator(Node *node, substitute_actual_srf_parameters_mutator, (void *) context); } + +/* + * Check whether a SELECT targetlist emits the specified column types, + * to see if it's safe to inline a function returning record. + * + * We insist on exact match here. The executor allows binary-coercible + * cases too, but we don't have a way to preserve the correct column types + * in the correct places if we inline the function in such a case. + * + * Note that we only check type OIDs not typmods; this agrees with what the + * executor would do at runtime, and attributing a specific typmod to a + * function result is largely wishful thinking anyway. + */ +static bool +tlist_matches_coltypelist(List *tlist, List *coltypelist) +{ + ListCell *tlistitem; + ListCell *clistitem; + + clistitem = list_head(coltypelist); + foreach(tlistitem, tlist) + { + TargetEntry *tle = (TargetEntry *) lfirst(tlistitem); + Oid coltype; + + if (tle->resjunk) + continue; /* ignore junk columns */ + + if (clistitem == NULL) + return false; /* too many tlist items */ + + coltype = lfirst_oid(clistitem); + clistitem = lnext(clistitem); + + if (exprType((Node *) tle->expr) != coltype) + return false; /* column type mismatch */ + } + + if (clistitem != NULL) + return false; /* too few tlist items */ + + return true; +} diff --git a/src/include/optimizer/clauses.h b/src/include/optimizer/clauses.h index 105924bb227..3623aade6a7 100644 --- a/src/include/optimizer/clauses.h +++ b/src/include/optimizer/clauses.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/optimizer/clauses.h,v 1.94 2008/08/25 22:42:34 tgl Exp $ + * $PostgreSQL: pgsql/src/include/optimizer/clauses.h,v 1.95 2008/10/09 19:27:40 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -77,6 +77,7 @@ extern Node *eval_const_expressions(PlannerInfo *root, Node *node); extern Node *estimate_expression_value(PlannerInfo *root, Node *node); -extern Query *inline_set_returning_function(PlannerInfo *root, Node *node); +extern Query *inline_set_returning_function(PlannerInfo *root, + RangeTblEntry *rte); #endif /* CLAUSES_H */ |