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path: root/src/backend/rewrite/rewriteManip.c
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Diffstat (limited to 'src/backend/rewrite/rewriteManip.c')
-rw-r--r--src/backend/rewrite/rewriteManip.c98
1 files changed, 45 insertions, 53 deletions
diff --git a/src/backend/rewrite/rewriteManip.c b/src/backend/rewrite/rewriteManip.c
index 0b07b5e9c46..cffe624deb4 100644
--- a/src/backend/rewrite/rewriteManip.c
+++ b/src/backend/rewrite/rewriteManip.c
@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteManip.c,v 1.49 2000/09/29 18:21:24 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteManip.c,v 1.50 2000/10/05 19:11:34 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -48,7 +48,7 @@ checkExprHasAggs(Node *node)
*/
if (node && IsA(node, Query))
return query_tree_walker((Query *) node, checkExprHasAggs_walker,
- NULL);
+ NULL, false);
else
return checkExprHasAggs_walker(node, NULL);
}
@@ -78,7 +78,7 @@ checkExprHasSubLink(Node *node)
*/
if (node && IsA(node, Query))
return query_tree_walker((Query *) node, checkExprHasSubLink_walker,
- NULL);
+ NULL, false);
else
return checkExprHasSubLink_walker(node, NULL);
}
@@ -101,7 +101,7 @@ checkExprHasSubLink_walker(Node *node, void *context)
* Find all Var nodes in the given tree with varlevelsup == sublevels_up,
* and increment their varno fields (rangetable indexes) by 'offset'.
* The varnoold fields are adjusted similarly. Also, RangeTblRef nodes
- * in join trees are adjusted.
+ * in join trees and setOp trees are adjusted.
*
* NOTE: although this has the form of a walker, we cheat and modify the
* nodes in-place. The given expression tree should have been copied
@@ -136,6 +136,7 @@ OffsetVarNodes_walker(Node *node, OffsetVarNodes_context *context)
if (context->sublevels_up == 0)
rtr->rtindex += context->offset;
+ /* the subquery itself is visited separately */
return false;
}
if (IsA(node, Query))
@@ -145,7 +146,7 @@ OffsetVarNodes_walker(Node *node, OffsetVarNodes_context *context)
context->sublevels_up++;
result = query_tree_walker((Query *) node, OffsetVarNodes_walker,
- (void *) context);
+ (void *) context, true);
context->sublevels_up--;
return result;
}
@@ -168,7 +169,7 @@ OffsetVarNodes(Node *node, int offset, int sublevels_up)
*/
if (node && IsA(node, Query))
query_tree_walker((Query *) node, OffsetVarNodes_walker,
- (void *) &context);
+ (void *) &context, true);
else
OffsetVarNodes_walker(node, &context);
}
@@ -179,7 +180,7 @@ OffsetVarNodes(Node *node, int offset, int sublevels_up)
* Find all Var nodes in the given tree belonging to a specific relation
* (identified by sublevels_up and rt_index), and change their varno fields
* to 'new_index'. The varnoold fields are changed too. Also, RangeTblRef
- * nodes in join trees are adjusted.
+ * nodes in join trees and setOp trees are adjusted.
*
* NOTE: although this has the form of a walker, we cheat and modify the
* nodes in-place. The given expression tree should have been copied
@@ -217,6 +218,7 @@ ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
if (context->sublevels_up == 0 &&
rtr->rtindex == context->rt_index)
rtr->rtindex = context->new_index;
+ /* the subquery itself is visited separately */
return false;
}
if (IsA(node, Query))
@@ -226,7 +228,7 @@ ChangeVarNodes_walker(Node *node, ChangeVarNodes_context *context)
context->sublevels_up++;
result = query_tree_walker((Query *) node, ChangeVarNodes_walker,
- (void *) context);
+ (void *) context, true);
context->sublevels_up--;
return result;
}
@@ -250,7 +252,7 @@ ChangeVarNodes(Node *node, int rt_index, int new_index, int sublevels_up)
*/
if (node && IsA(node, Query))
query_tree_walker((Query *) node, ChangeVarNodes_walker,
- (void *) &context);
+ (void *) &context, true);
else
ChangeVarNodes_walker(node, &context);
}
@@ -300,7 +302,7 @@ IncrementVarSublevelsUp_walker(Node *node,
context->min_sublevels_up++;
result = query_tree_walker((Query *) node,
IncrementVarSublevelsUp_walker,
- (void *) context);
+ (void *) context, true);
context->min_sublevels_up--;
return result;
}
@@ -324,7 +326,7 @@ IncrementVarSublevelsUp(Node *node, int delta_sublevels_up,
*/
if (node && IsA(node, Query))
query_tree_walker((Query *) node, IncrementVarSublevelsUp_walker,
- (void *) &context);
+ (void *) &context, true);
else
IncrementVarSublevelsUp_walker(node, &context);
}
@@ -332,7 +334,7 @@ IncrementVarSublevelsUp(Node *node, int delta_sublevels_up,
/*
* rangeTableEntry_used - detect whether an RTE is referenced somewhere
- * in var nodes or jointree nodes of a query or expression.
+ * in var nodes or join or setOp trees of a query or expression.
*/
typedef struct
@@ -363,6 +365,7 @@ rangeTableEntry_used_walker(Node *node,
if (rtr->rtindex == context->rt_index &&
context->sublevels_up == 0)
return true;
+ /* the subquery itself is visited separately */
return false;
}
if (IsA(node, Query))
@@ -372,7 +375,7 @@ rangeTableEntry_used_walker(Node *node,
context->sublevels_up++;
result = query_tree_walker((Query *) node, rangeTableEntry_used_walker,
- (void *) context);
+ (void *) context, true);
context->sublevels_up--;
return result;
}
@@ -395,7 +398,7 @@ rangeTableEntry_used(Node *node, int rt_index, int sublevels_up)
*/
if (node && IsA(node, Query))
return query_tree_walker((Query *) node, rangeTableEntry_used_walker,
- (void *) &context);
+ (void *) &context, true);
else
return rangeTableEntry_used_walker(node, &context);
}
@@ -437,7 +440,7 @@ attribute_used_walker(Node *node,
context->sublevels_up++;
result = query_tree_walker((Query *) node, attribute_used_walker,
- (void *) context);
+ (void *) context, true);
context->sublevels_up--;
return result;
}
@@ -461,7 +464,7 @@ attribute_used(Node *node, int rt_index, int attno, int sublevels_up)
*/
if (node && IsA(node, Query))
return query_tree_walker((Query *) node, attribute_used_walker,
- (void *) &context);
+ (void *) &context, true);
else
return attribute_used_walker(node, &context);
}
@@ -681,10 +684,8 @@ ResolveNew_mutator(Node *node, ResolveNew_context *context)
FLATCOPY(newnode, sublink, SubLink);
MUTATE(newnode->lefthand, sublink->lefthand, List *,
ResolveNew_mutator, context);
- context->sublevels_up++;
MUTATE(newnode->subselect, sublink->subselect, Node *,
ResolveNew_mutator, context);
- context->sublevels_up--;
return (Node *) newnode;
}
if (IsA(node, Query))
@@ -693,12 +694,9 @@ ResolveNew_mutator(Node *node, ResolveNew_context *context)
Query *newnode;
FLATCOPY(newnode, query, Query);
- MUTATE(newnode->targetList, query->targetList, List *,
- ResolveNew_mutator, context);
- MUTATE(newnode->jointree, query->jointree, FromExpr *,
- ResolveNew_mutator, context);
- MUTATE(newnode->havingQual, query->havingQual, Node *,
- ResolveNew_mutator, context);
+ context->sublevels_up++;
+ query_tree_mutator(newnode, ResolveNew_mutator, context, true);
+ context->sublevels_up--;
return (Node *) newnode;
}
return expression_tree_mutator(node, ResolveNew_mutator,
@@ -718,11 +716,22 @@ ResolveNew(Node *node, int target_varno, int sublevels_up,
context.update_varno = update_varno;
/*
- * Note: if an entire Query is passed, the right things will happen,
- * because ResolveNew_mutator increments sublevels_up when it sees
- * a SubLink, not a Query.
+ * Must be prepared to start with a Query or a bare expression tree;
+ * if it's a Query, go straight to query_tree_mutator to make sure that
+ * sublevels_up doesn't get incremented prematurely.
*/
- return ResolveNew_mutator(node, &context);
+ if (node && IsA(node, Query))
+ {
+ Query *query = (Query *) node;
+ Query *newnode;
+
+ FLATCOPY(newnode, query, Query);
+ query_tree_mutator(newnode, ResolveNew_mutator,
+ (void *) &context, true);
+ return (Node *) newnode;
+ }
+ else
+ return ResolveNew_mutator(node, &context);
}
/*
@@ -740,12 +749,8 @@ FixNew(RewriteInfo *info, Query *parsetree)
context.event = info->event;
context.update_varno = info->current_varno;
- info->rule_action->targetList = (List *)
- ResolveNew_mutator((Node *) info->rule_action->targetList, &context);
- info->rule_action->jointree = (FromExpr *)
- ResolveNew_mutator((Node *) info->rule_action->jointree, &context);
- info->rule_action->havingQual =
- ResolveNew_mutator(info->rule_action->havingQual, &context);
+ query_tree_mutator(info->rule_action, ResolveNew_mutator,
+ (void *) &context, true);
}
@@ -837,10 +842,8 @@ HandleRIRAttributeRule_mutator(Node *node,
FLATCOPY(newnode, sublink, SubLink);
MUTATE(newnode->lefthand, sublink->lefthand, List *,
HandleRIRAttributeRule_mutator, context);
- context->sublevels_up++;
MUTATE(newnode->subselect, sublink->subselect, Node *,
HandleRIRAttributeRule_mutator, context);
- context->sublevels_up--;
return (Node *) newnode;
}
if (IsA(node, Query))
@@ -849,14 +852,10 @@ HandleRIRAttributeRule_mutator(Node *node,
Query *newnode;
FLATCOPY(newnode, query, Query);
- MUTATE(newnode->targetList, query->targetList, List *,
- HandleRIRAttributeRule_mutator, context);
- MUTATE(newnode->jointree, query->jointree, FromExpr *,
- HandleRIRAttributeRule_mutator, context);
- MUTATE(newnode->havingQual, query->havingQual, Node *,
- HandleRIRAttributeRule_mutator, context);
-
-
+ context->sublevels_up++;
+ query_tree_mutator(newnode, HandleRIRAttributeRule_mutator,
+ context, true);
+ context->sublevels_up--;
return (Node *) newnode;
}
return expression_tree_mutator(node, HandleRIRAttributeRule_mutator,
@@ -882,15 +881,8 @@ HandleRIRAttributeRule(Query *parsetree,
context.badsql = badsql;
context.sublevels_up = 0;
- parsetree->targetList = (List *)
- HandleRIRAttributeRule_mutator((Node *) parsetree->targetList,
- &context);
- parsetree->jointree = (FromExpr *)
- HandleRIRAttributeRule_mutator((Node *) parsetree->jointree,
- &context);
- parsetree->havingQual =
- HandleRIRAttributeRule_mutator(parsetree->havingQual,
- &context);
+ query_tree_mutator(parsetree, HandleRIRAttributeRule_mutator,
+ (void *) &context, true);
}
#endif /* NOT_USED */
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-22 06:48:11 +0000