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IN clauses appearing at top level of WHERE can now be handled as joins.

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There are two implementation techniques: the executor understands a new
JOIN_IN jointype, which emits at most one matching row per left-hand row,
or the result of the IN's sub-select can be fed through a DISTINCT filter
and then joined as an ordinary relation.
Along the way, some minor code cleanup in the optimizer; notably, break
out most of the jointree-rearrangement preprocessing in planner.c and
put it in a new file prep/prepjointree.c.
This commit is contained in:
Tom Lane
2003-01-20 18:55:07 +00:00
parent be2b660ecd
commit bdfbfde1b1
47 changed files with 2075 additions and 875 deletions
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70
src/backend/optimizer/prep/prepunion.c
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@ -14,7 +14,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/prep/prepunion.c,v 1.87 2003/01/17 02:01:16 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/prep/prepunion.c,v 1.88 2003/01/20 18:54:54 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -62,6 +62,7 @@ static List *generate_append_tlist(List *colTypes, bool flag,
List *refnames_tlist);
static Node *adjust_inherited_attrs_mutator(Node *node,
adjust_inherited_attrs_context *context);
static List *adjust_rtindex_list(List *relids, Index oldrelid, Index newrelid);
static List *adjust_inherited_tlist(List *tlist, Oid new_relid);
@ -239,8 +240,9 @@ generate_union_plan(SetOperationStmt *op, Query *parse,
tlist = new_unsorted_tlist(tlist);
sortList = addAllTargetsToSortList(NIL, tlist);
plan = make_sortplan(parse, tlist, plan, sortList);
plan = (Plan *) make_unique(tlist, plan, copyObject(sortList));
plan = (Plan *) make_sort_from_sortclauses(parse, tlist,
plan, sortList);
plan = (Plan *) make_unique(tlist, plan, sortList);
}
return plan;
}
@ -292,7 +294,7 @@ generate_nonunion_plan(SetOperationStmt *op, Query *parse,
*/
tlist = new_unsorted_tlist(tlist);
sortList = addAllTargetsToSortList(NIL, tlist);
plan = make_sortplan(parse, tlist, plan, sortList);
plan = (Plan *) make_sort_from_sortclauses(parse, tlist, plan, sortList);
switch (op->op)
{
case SETOP_INTERSECT:
@ -830,6 +832,23 @@ adjust_inherited_attrs_mutator(Node *node,
j->rtindex = context->new_rt_index;
return (Node *) j;
}
if (IsA(node, InClauseInfo))
{
/* Copy the InClauseInfo node with correct mutation of subnodes */
InClauseInfo *ininfo;
ininfo = (InClauseInfo *) expression_tree_mutator(node,
adjust_inherited_attrs_mutator,
(void *) context);
/* now fix InClauseInfo's rtindex lists */
ininfo->lefthand = adjust_rtindex_list(ininfo->lefthand,
context->old_rt_index,
context->new_rt_index);
ininfo->righthand = adjust_rtindex_list(ininfo->righthand,
context->old_rt_index,
context->new_rt_index);
return (Node *) ininfo;
}
/*
* We have to process RestrictInfo nodes specially.
@ -856,26 +875,12 @@ adjust_inherited_attrs_mutator(Node *node,
/*
* Adjust left/right relids lists too.
*/
if (intMember(context->old_rt_index, oldinfo->left_relids))
{
newinfo->left_relids = listCopy(oldinfo->left_relids);
newinfo->left_relids = lremovei(context->old_rt_index,
newinfo->left_relids);
newinfo->left_relids = lconsi(context->new_rt_index,
newinfo->left_relids);
}
else
newinfo->left_relids = oldinfo->left_relids;
if (intMember(context->old_rt_index, oldinfo->right_relids))
{
newinfo->right_relids = listCopy(oldinfo->right_relids);
newinfo->right_relids = lremovei(context->old_rt_index,
newinfo->right_relids);
newinfo->right_relids = lconsi(context->new_rt_index,
newinfo->right_relids);
}
else
newinfo->right_relids = oldinfo->right_relids;
newinfo->left_relids = adjust_rtindex_list(oldinfo->left_relids,
context->old_rt_index,
context->new_rt_index);
newinfo->right_relids = adjust_rtindex_list(oldinfo->right_relids,
context->old_rt_index,
context->new_rt_index);
newinfo->eval_cost.startup = -1; /* reset these too */
newinfo->this_selec = -1;
@ -922,6 +927,23 @@ adjust_inherited_attrs_mutator(Node *node,
(void *) context);
}
/*
* Substitute newrelid for oldrelid in a list of RT indexes
*/
static List *
adjust_rtindex_list(List *relids, Index oldrelid, Index newrelid)
{
if (intMember(oldrelid, relids))
{
/* Ensure we have a modifiable copy */
relids = listCopy(relids);
/* Remove old, add new */
relids = lremovei(oldrelid, relids);
relids = lconsi(newrelid, relids);
}
return relids;
}
/*
* Adjust the targetlist entries of an inherited UPDATE operation
*