diff options
Diffstat (limited to 'src/backend/rewrite/rewriteManip.c')
| -rw-r--r-- | src/backend/rewrite/rewriteManip.c | 38 |
1 files changed, 25 insertions, 13 deletions
diff --git a/src/backend/rewrite/rewriteManip.c b/src/backend/rewrite/rewriteManip.c index 1202c31314d..baa9330016f 100644 --- a/src/backend/rewrite/rewriteManip.c +++ b/src/backend/rewrite/rewriteManip.c @@ -7,7 +7,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/rewrite/rewriteManip.c,v 1.109 2008/08/14 20:31:29 heikki Exp $ + * $PostgreSQL: pgsql/src/backend/rewrite/rewriteManip.c,v 1.110 2008/08/22 00:16:04 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -25,10 +25,10 @@ typedef struct { int sublevels_up; -} checkExprHasAggs_context; +} contain_aggs_of_level_context; -static bool checkExprHasAggs_walker(Node *node, - checkExprHasAggs_context *context); +static bool contain_aggs_of_level_walker(Node *node, + contain_aggs_of_level_context *context); static bool checkExprHasSubLink_walker(Node *node, void *context); static Relids offset_relid_set(Relids relids, int offset); static Relids adjust_relid_set(Relids relids, int oldrelid, int newrelid); @@ -37,32 +37,44 @@ static Relids adjust_relid_set(Relids relids, int oldrelid, int newrelid); /* * checkExprHasAggs - * Check if an expression contains an aggregate function call. + */ +bool +checkExprHasAggs(Node *node) +{ + return contain_aggs_of_level(node, 0); +} + +/* + * contain_aggs_of_level - + * Check if an expression contains an aggregate function call of a + * specified query level. * * The objective of this routine is to detect whether there are aggregates - * belonging to the initial query level. Aggregates belonging to subqueries + * belonging to the given query level. Aggregates belonging to subqueries * or outer queries do NOT cause a true result. We must recurse into * subqueries to detect outer-reference aggregates that logically belong to - * the initial query level. + * the specified query level. */ bool -checkExprHasAggs(Node *node) +contain_aggs_of_level(Node *node, int levelsup) { - checkExprHasAggs_context context; + contain_aggs_of_level_context context; - context.sublevels_up = 0; + context.sublevels_up = levelsup; /* * Must be prepared to start with a Query or a bare expression tree; if * it's a Query, we don't want to increment sublevels_up. */ return query_or_expression_tree_walker(node, - checkExprHasAggs_walker, + contain_aggs_of_level_walker, (void *) &context, 0); } static bool -checkExprHasAggs_walker(Node *node, checkExprHasAggs_context *context) +contain_aggs_of_level_walker(Node *node, + contain_aggs_of_level_context *context) { if (node == NULL) return false; @@ -79,12 +91,12 @@ checkExprHasAggs_walker(Node *node, checkExprHasAggs_context *context) context->sublevels_up++; result = query_tree_walker((Query *) node, - checkExprHasAggs_walker, + contain_aggs_of_level_walker, (void *) context, 0); context->sublevels_up--; return result; } - return expression_tree_walker(node, checkExprHasAggs_walker, + return expression_tree_walker(node, contain_aggs_of_level_walker, (void *) context); } |