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Make subqueries rewrite properly.

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This commit is contained in:
Bruce Momjian 1998-01-21 04:24:46 +00:00
parent 7e46348e62
commit 0f413d2dc2
4 changed files with 237 additions and 106 deletions
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33
src/backend/rewrite/locks.c
View File

@ -6,7 +6,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/rewrite/Attic/locks.c,v 1.7 1998/01/15 19:00:06 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/rewrite/Attic/locks.c,v 1.8 1998/01/21 04:24:34 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -27,7 +27,8 @@
* otherwise, we return false
*/
static bool
nodeThisLockWasTriggered(Node *node, int varno, AttrNumber attnum)
nodeThisLockWasTriggered(Node *node, int varno, AttrNumber attnum,
int sublevels_up)
{
if (node == NULL)
return FALSE;
@ -46,24 +47,24 @@ nodeThisLockWasTriggered(Node *node, int varno, AttrNumber attnum)
{
Expr *expr = (Expr *) node;
return
nodeThisLockWasTriggered((Node *) expr->args, varno, attnum);
return nodeThisLockWasTriggered((Node *) expr->args, varno,
attnum, sublevels_up);
}
break;
case T_TargetEntry:
{
TargetEntry *tle = (TargetEntry *) node;
return
nodeThisLockWasTriggered(tle->expr, varno, attnum);
return nodeThisLockWasTriggered(tle->expr, varno, attnum,
sublevels_up);
}
break;
case T_Aggreg:
{
Aggreg *agg = (Aggreg *) node;
return
nodeThisLockWasTriggered(agg->target, varno, attnum);
return nodeThisLockWasTriggered(agg->target, varno, attnum,
sublevels_up);
}
break;
case T_List:
@ -72,12 +73,22 @@ nodeThisLockWasTriggered(Node *node, int varno, AttrNumber attnum)
foreach(l, (List *) node)
{
if (nodeThisLockWasTriggered(lfirst(l), varno, attnum))
if (nodeThisLockWasTriggered(lfirst(l), varno, attnum,
sublevels_up))
return TRUE;
}
return FALSE;
}
break;
case T_SubLink:
{
SubLink *sublink = (SubLink *) node;
Query *query = (Query *)sublink->subselect;
return nodeThisLockWasTriggered(query->qual, varno, attnum,
sublevels_up + 1);
}
break;
default:
break;
}
@ -96,10 +107,10 @@ thisLockWasTriggered(int varno,
Query *parsetree)
{
if (nodeThisLockWasTriggered(parsetree->qual, varno, attnum))
if (nodeThisLockWasTriggered(parsetree->qual, varno, attnum, 0))
return true;
if (nodeThisLockWasTriggered((Node *) parsetree->targetList, varno, attnum))
if (nodeThisLockWasTriggered((Node *) parsetree->targetList, varno, attnum, 0))
return true;
return false;

100
src/backend/rewrite/rewriteHandler.c
View File

@ -6,7 +6,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.10 1998/01/09 05:48:17 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.11 1998/01/21 04:24:36 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -29,12 +29,12 @@
#include "commands/creatinh.h"
#include "access/heapam.h"
static void
ApplyRetrieveRule(Query *parsetree, RewriteRule *rule,
static void ApplyRetrieveRule(Query *parsetree, RewriteRule *rule,
int rt_index, int relation_level, int *modified);
static List *
fireRules(Query *parsetree, int rt_index, CmdType event,
static List *fireRules(Query *parsetree, int rt_index, CmdType event,
bool *instead_flag, List *locks, List **qual_products);
static void QueryRewriteSubLink(Node *node);
static List *QueryRewriteOne(Query *parsetree);
static List *deepRewriteQuery(Query *parsetree);
/*
@ -77,11 +77,11 @@ gatherRewriteMeta(Query *parsetree,
OffsetVarNodes((Node *) info->rule_action->targetList, rt_length);
OffsetVarNodes(info->rule_qual, rt_length);
ChangeVarNodes((Node *) info->rule_action->qual,
PRS2_CURRENT_VARNO + rt_length, rt_index);
PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
ChangeVarNodes((Node *) info->rule_action->targetList,
PRS2_CURRENT_VARNO + rt_length, rt_index);
PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
ChangeVarNodes(info->rule_qual,
PRS2_CURRENT_VARNO + rt_length, rt_index);
PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
/*
* bug here about replace CURRENT -- sort of replace current is
@ -292,10 +292,10 @@ ApplyRetrieveRule(Query *parsetree,
OffsetVarNodes((Node *) rule_action->targetList, rt_length);
OffsetVarNodes(rule_qual, rt_length);
ChangeVarNodes(rule_action->qual,
PRS2_CURRENT_VARNO + rt_length, rt_index);
PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
ChangeVarNodes((Node *) rule_action->targetList,
PRS2_CURRENT_VARNO + rt_length, rt_index);
ChangeVarNodes(rule_qual, PRS2_CURRENT_VARNO + rt_length, rt_index);
PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
ChangeVarNodes(rule_qual, PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
if (relation_level)
{
HandleViewRule(parsetree, rtable, rule_action->targetList, rt_index,
@ -402,7 +402,7 @@ CopyAndAddQual(Query *parsetree,
rtable = append(rtable, listCopy(rule_action->rtable));
new_tree->rtable = rtable;
OffsetVarNodes(new_qual, rt_length);
ChangeVarNodes(new_qual, PRS2_CURRENT_VARNO + rt_length, rt_index);
ChangeVarNodes(new_qual, PRS2_CURRENT_VARNO + rt_length, rt_index, 0);
}
/* XXX -- where current doesn't work for instead nothing.... yet */
AddNotQual(new_tree, new_qual);
@ -627,6 +627,82 @@ static int numQueryRewriteInvoked = 0;
*/
List *
QueryRewrite(Query *parsetree)
{
QueryRewriteSubLink(parsetree->qual);
return QueryRewriteOne(parsetree);
}
/*
* QueryRewriteSubLink
*
* This rewrites the SubLink subqueries first, doing the lowest ones first.
* We already have code in the main rewrite loops to process correlated
* variables from upper queries that exist in subqueries.
*/
static void
QueryRewriteSubLink(Node *node)
{
if (node == NULL)
return;
switch (nodeTag(node))
{
case T_TargetEntry:
break;
case T_Aggreg:
break;
case T_Expr:
{
Expr *expr = (Expr *) node;
QueryRewriteSubLink((Node *)expr->args);
}
break;
case T_Var:
break;
case T_List:
{
List *l;
foreach(l, (List *) node)
QueryRewriteSubLink(lfirst(l));
}
break;
case T_SubLink:
{
SubLink *sublink = (SubLink *) node;
Query *query = (Query *)sublink->subselect;
List *ret;
/*
* Nest down first. We do this so if a rewrite adds a
* SubLink we don't process it as part of this loop.
*/
QueryRewriteSubLink((Node *)query->qual);
ret = QueryRewriteOne(query);
if (!ret)
sublink->subselect = NULL;
else if (lnext(ret) == NIL)
sublink->subselect = lfirst(ret);
else
elog(ERROR,"Don't know how to process subquery that rewrites to multiple queries.");
}
break;
default:
/* ignore the others */
break;
}
return;
}
/*
* QueryOneRewrite -
* rewrite one query
*/
static List *
QueryRewriteOne(Query *parsetree)
{
numQueryRewriteInvoked = 0;

205
src/backend/rewrite/rewriteManip.c
View File

@ -6,7 +6,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteManip.c,v 1.10 1998/01/15 19:00:07 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteManip.c,v 1.11 1998/01/21 04:24:39 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -28,7 +28,8 @@
#include "nodes/plannodes.h"
#include "optimizer/clauses.h"
static void ResolveNew(RewriteInfo *info, List *targetlist, Node **node);
static void ResolveNew(RewriteInfo *info, List *targetlist,
Node **node, int sublevels_up);
@ -85,7 +86,7 @@ OffsetVarNodes(Node *node, int offset)
}
void
ChangeVarNodes(Node *node, int old_varno, int new_varno)
ChangeVarNodes(Node *node, int old_varno, int new_varno, int sublevels_up)
{
if (node == NULL)
return;
@ -95,28 +96,29 @@ ChangeVarNodes(Node *node, int old_varno, int new_varno)
{
TargetEntry *tle = (TargetEntry *) node;
ChangeVarNodes(tle->expr, old_varno, new_varno);
ChangeVarNodes(tle->expr, old_varno, new_varno, sublevels_up);
}
break;
case T_Aggreg:
{
Aggreg *agg = (Aggreg *) node;
ChangeVarNodes(agg->target, old_varno, new_varno);
ChangeVarNodes(agg->target, old_varno, new_varno, sublevels_up);
}
break;
case T_Expr:
{
Expr *expr = (Expr *) node;
ChangeVarNodes((Node *) expr->args, old_varno, new_varno);
ChangeVarNodes((Node *) expr->args, old_varno, new_varno, sublevels_up);
}
break;
case T_Var:
{
Var *var = (Var *) node;
if (var->varno == old_varno)
if (var->varno == old_varno &&
var->varlevelsup == sublevels_up)
{
var->varno = new_varno;
var->varnoold = new_varno;
@ -128,9 +130,16 @@ ChangeVarNodes(Node *node, int old_varno, int new_varno)
List *l;
foreach(l, (List *) node)
{
ChangeVarNodes(lfirst(l), old_varno, new_varno);
}
ChangeVarNodes(lfirst(l), old_varno, new_varno, sublevels_up);
}
break;
case T_SubLink:
{
SubLink *sublink = (SubLink *) node;
Query *query = (Query *)sublink->subselect;
ChangeVarNodes((Node *)query->qual, old_varno, new_varno,
sublevels_up + 1);
}
break;
default:
@ -237,7 +246,8 @@ FindMatchingTLEntry(List *tlist, char *e_attname)
}
static void
ResolveNew(RewriteInfo *info, List *targetlist, Node **nodePtr)
ResolveNew(RewriteInfo *info, List *targetlist, Node **nodePtr,
int sublevels_up)
{
Node *node = *nodePtr;
@ -247,20 +257,25 @@ ResolveNew(RewriteInfo *info, List *targetlist, Node **nodePtr)
switch (nodeTag(node))
{
case T_TargetEntry:
ResolveNew(info, targetlist, &((TargetEntry *) node)->expr);
ResolveNew(info, targetlist, &((TargetEntry *) node)->expr,
sublevels_up);
break;
case T_Aggreg:
ResolveNew(info, targetlist, &((Aggreg *) node)->target);
ResolveNew(info, targetlist, &((Aggreg *) node)->target,
sublevels_up);
break;
case T_Expr:
ResolveNew(info, targetlist, (Node **) (&(((Expr *) node)->args)));
ResolveNew(info, targetlist, (Node **) (&(((Expr *) node)->args)),
sublevels_up);
break;
case T_Var:
{
int this_varno = (int) ((Var *) node)->varno;
Node *n;
int this_varno = (int) ((Var *) node)->varno;
int this_varlevelsup = (int) ((Var *) node)->varlevelsup;
Node *n;
if (this_varno == info->new_varno)
if (this_varno == info->new_varno &&
this_varlevelsup == sublevels_up)
{
n = FindMatchingNew(targetlist,
((Var *) node)->varattno);
@ -288,11 +303,18 @@ ResolveNew(RewriteInfo *info, List *targetlist, Node **nodePtr)
List *l;
foreach(l, (List *) node)
{
ResolveNew(info, targetlist, (Node **) &(lfirst(l)));
}
ResolveNew(info, targetlist, (Node **) &(lfirst(l)),
sublevels_up);
break;
}
case T_SubLink:
{
SubLink *sublink = (SubLink *) node;
Query *query = (Query *)sublink->subselect;
ResolveNew(info, targetlist, (Node **)&(query->qual), sublevels_up + 1);
}
break;
default:
/* ignore the others */
break;
@ -303,8 +325,8 @@ void
FixNew(RewriteInfo *info, Query *parsetree)
{
ResolveNew(info, parsetree->targetList,
(Node **) &(info->rule_action->targetList));
ResolveNew(info, parsetree->targetList, &info->rule_action->qual);
(Node **) &(info->rule_action->targetList), 0);
ResolveNew(info, parsetree->targetList, &info->rule_action->qual, 0);
}
static void
@ -314,7 +336,8 @@ nodeHandleRIRAttributeRule(Node **nodePtr,
int rt_index,
int attr_num,
int *modified,
int *badsql)
int *badsql,
int sublevels_up)
{
Node *node = *nodePtr;
@ -322,24 +345,13 @@ nodeHandleRIRAttributeRule(Node **nodePtr,
return;
switch (nodeTag(node))
{
case T_List:
{
List *i;
foreach(i, (List *) node)
{
nodeHandleRIRAttributeRule((Node **) (&(lfirst(i))), rtable,
targetlist, rt_index, attr_num,
modified, badsql);
}
}
break;
case T_TargetEntry:
{
TargetEntry *tle = (TargetEntry *) node;
nodeHandleRIRAttributeRule(&tle->expr, rtable, targetlist,
rt_index, attr_num, modified, badsql);
rt_index, attr_num, modified, badsql,
sublevels_up);
}
break;
case T_Aggreg:
@ -347,7 +359,8 @@ nodeHandleRIRAttributeRule(Node **nodePtr,
Aggreg *agg = (Aggreg *) node;
nodeHandleRIRAttributeRule(&agg->target, rtable, targetlist,
rt_index, attr_num, modified, badsql);
rt_index, attr_num, modified, badsql,
sublevels_up);
}
break;
case T_Expr:
@ -356,18 +369,19 @@ nodeHandleRIRAttributeRule(Node **nodePtr,
nodeHandleRIRAttributeRule((Node **) (&(expr->args)), rtable,
targetlist, rt_index, attr_num,
modified, badsql);
modified, badsql,
sublevels_up);
}
break;
case T_Var:
{
int this_varno = (int) ((Var *) node)->varno;
NameData name_to_look_for;
MemSet(name_to_look_for.data, 0, NAMEDATALEN);
int this_varno = ((Var *) node)->varno;
int this_varattno = ((Var *) node)->varattno;
int this_varlevelsup = ((Var *) node)->varlevelsup;
if (this_varno == rt_index &&
((Var *) node)->varattno == attr_num)
this_varattno == attr_num &&
this_varlevelsup == sublevels_up)
{
if (((Var *) node)->vartype == 32)
{ /* HACK */
@ -378,29 +392,50 @@ nodeHandleRIRAttributeRule(Node **nodePtr,
}
else
{
NameData name_to_look_for;
name_to_look_for.data[0] = '\0';
namestrcpy(&name_to_look_for,
(char *) get_attname(getrelid(this_varno,
rtable),
attr_num));
if (name_to_look_for.data[0])
{
Node *n;
n = FindMatchingTLEntry(targetlist, (char *) &name_to_look_for);
if (n == NULL)
*nodePtr = make_null(((Var *) node)->vartype);
else
*nodePtr = n;
*modified = TRUE;
}
}
}
if (name_to_look_for.data[0])
{
Node *n;
}
break;
case T_List:
{
List *i;
n = FindMatchingTLEntry(targetlist, (char *) &name_to_look_for);
if (n == NULL)
{
*nodePtr = make_null(((Var *) node)->vartype);
}
else
{
*nodePtr = n;
}
*modified = TRUE;
foreach(i, (List *) node)
{
nodeHandleRIRAttributeRule((Node **) (&(lfirst(i))), rtable,
targetlist, rt_index, attr_num,
modified, badsql, sublevels_up);
}
}
break;
case T_SubLink:
{
SubLink *sublink = (SubLink *) node;
Query *query = (Query *)sublink->subselect;
nodeHandleRIRAttributeRule((Node **)&(query->qual), rtable, targetlist,
rt_index, attr_num, modified, badsql,
sublevels_up + 1);
}
break;
default:
/* ignore the others */
break;
@ -423,9 +458,9 @@ HandleRIRAttributeRule(Query *parsetree,
nodeHandleRIRAttributeRule((Node **) (&(parsetree->targetList)), rtable,
targetlist, rt_index, attr_num,
modified, badsql);
modified, badsql, 0);
nodeHandleRIRAttributeRule(&parsetree->qual, rtable, targetlist,
rt_index, attr_num, modified, badsql);
rt_index, attr_num, modified, badsql, 0);
}
@ -434,7 +469,8 @@ nodeHandleViewRule(Node **nodePtr,
List *rtable,
List *targetlist,
int rt_index,
int *modified)
int *modified,
int sublevels_up)
{
Node *node = *nodePtr;
@ -443,24 +479,12 @@ nodeHandleViewRule(Node **nodePtr,
switch (nodeTag(node))
{
case T_List:
{
List *l;
foreach(l, (List *) node)
{
nodeHandleViewRule((Node **) (&(lfirst(l))),
rtable, targetlist,
rt_index, modified);
}
}
break;
case T_TargetEntry:
{
TargetEntry *tle = (TargetEntry *) node;
nodeHandleViewRule(&(tle->expr), rtable, targetlist,
rt_index, modified);
rt_index, modified, sublevels_up);
}
break;
case T_Aggreg:
@ -468,7 +492,7 @@ nodeHandleViewRule(Node **nodePtr,
Aggreg *agg = (Aggreg *) node;
nodeHandleViewRule(&(agg->target), rtable, targetlist,
rt_index, modified);
rt_index, modified, sublevels_up);
}
break;
case T_Expr:
@ -477,33 +501,52 @@ nodeHandleViewRule(Node **nodePtr,
nodeHandleViewRule((Node **) (&(expr->args)),
rtable, targetlist,
rt_index, modified);
rt_index, modified, sublevels_up);
}
break;
case T_Var:
{
Var *var = (Var *) node;
int this_varno = var->varno;
int this_varlevelsup = var->varlevelsup;
Node *n;
if (this_varno == rt_index)
if (this_varno == rt_index &&
this_varlevelsup == sublevels_up)
{
n = FindMatchingTLEntry(targetlist,
get_attname(getrelid(this_varno,
rtable),
var->varattno));
if (n == NULL)
{
*nodePtr = make_null(((Var *) node)->vartype);
}
else
{
*nodePtr = n;
}
*modified = TRUE;
}
break;
}
case T_List:
{
List *l;
foreach(l, (List *) node)
{
nodeHandleViewRule((Node **) (&(lfirst(l))),
rtable, targetlist,
rt_index, modified, sublevels_up);
}
}
break;
case T_SubLink:
{
SubLink *sublink = (SubLink *) node;
Query *query = (Query *)sublink->subselect;
nodeHandleViewRule((Node **)&(query->qual), rtable, targetlist,
rt_index, modified, sublevels_up + 1);
}
break;
default:
/* ignore the others */
break;
@ -519,7 +562,7 @@ HandleViewRule(Query *parsetree,
{
nodeHandleViewRule(&parsetree->qual, rtable, targetlist, rt_index,
modified);
modified, 0);
nodeHandleViewRule((Node **) (&(parsetree->targetList)), rtable, targetlist,
rt_index, modified);
rt_index, modified, 0);
}

5
src/include/rewrite/rewriteManip.h
View File

@ -6,7 +6,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: rewriteManip.h,v 1.5 1997/11/26 01:14:25 momjian Exp $
* $Id: rewriteManip.h,v 1.6 1998/01/21 04:24:46 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -19,7 +19,8 @@
/* RewriteManip.c */
void OffsetVarNodes(Node *node, int offset);
void ChangeVarNodes(Node *node, int old_varno, int new_varno);
void ChangeVarNodes(Node *node, int old_varno, int new_varno,
int sublevels_up);
void AddQual(Query *parsetree, Node *qual);
void AddNotQual(Query *parsetree, Node *qual);
void FixResdomTypes(List *user_tlist);