diff options
Diffstat (limited to 'src/backend/optimizer/util/clauses.c')
| -rw-r--r-- | src/backend/optimizer/util/clauses.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c index 0c2e652c79..3f4ced5a55 100644 --- a/src/backend/optimizer/util/clauses.c +++ b/src/backend/optimizer/util/clauses.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.138 2003/05/28 22:32:49 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/optimizer/util/clauses.c,v 1.139 2003/06/06 15:04:02 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -308,6 +308,13 @@ make_ands_implicit(Expr *clause) * Recursively search for Aggref nodes within a clause. * * Returns true if any aggregate found. + * + * This does not descend into subqueries, and so should be used only after + * reduction of sublinks to subplans, or in contexts where it's known there + * are no subqueries. There mustn't be outer-aggregate references either. + * + * (If you want something like this but able to deal with subqueries, + * see rewriteManip.c's checkExprHasAggs().) */ bool contain_agg_clause(Node *clause) @@ -321,8 +328,12 @@ contain_agg_clause_walker(Node *node, void *context) if (node == NULL) return false; if (IsA(node, Aggref)) + { + Assert(((Aggref *) node)->agglevelsup == 0); return true; /* abort the tree traversal and return * true */ + } + Assert(!IsA(node, SubLink)); return expression_tree_walker(node, contain_agg_clause_walker, context); } @@ -331,6 +342,10 @@ contain_agg_clause_walker(Node *node, void *context) * Recursively search for DISTINCT Aggref nodes within a clause. * * Returns true if any DISTINCT aggregate found. + * + * This does not descend into subqueries, and so should be used only after + * reduction of sublinks to subplans, or in contexts where it's known there + * are no subqueries. There mustn't be outer-aggregate references either. */ bool contain_distinct_agg_clause(Node *clause) @@ -345,10 +360,12 @@ contain_distinct_agg_clause_walker(Node *node, void *context) return false; if (IsA(node, Aggref)) { + Assert(((Aggref *) node)->agglevelsup == 0); if (((Aggref *) node)->aggdistinct) return true; /* abort the tree traversal and return * true */ } + Assert(!IsA(node, SubLink)); return expression_tree_walker(node, contain_distinct_agg_clause_walker, context); } @@ -357,6 +374,10 @@ contain_distinct_agg_clause_walker(Node *node, void *context) * Recursively count the Aggref nodes in an expression tree. * * Note: this also checks for nested aggregates, which are an error. + * + * This does not descend into subqueries, and so should be used only after + * reduction of sublinks to subplans, or in contexts where it's known there + * are no subqueries. There mustn't be outer-aggregate references either. */ int count_agg_clause(Node *clause) @@ -374,6 +395,7 @@ count_agg_clause_walker(Node *node, int *count) return false; if (IsA(node, Aggref)) { + Assert(((Aggref *) node)->agglevelsup == 0); (*count)++; /* @@ -388,6 +410,7 @@ count_agg_clause_walker(Node *node, int *count) */ return false; } + Assert(!IsA(node, SubLink)); return expression_tree_walker(node, count_agg_clause_walker, (void *) count); } |