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Allow index use with OR clauses.

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This commit is contained in:
Bruce Momjian
1998-08-01 22:12:13 +00:00
parent 0668aa8817
commit 0a2e5cdfc9
9 changed files with 289 additions and 318 deletions
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94
src/backend/optimizer/path/orindxpath.c
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@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/orindxpath.c,v 1.7 1998/07/18 04:22:33 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/orindxpath.c,v 1.8 1998/08/01 22:12:13 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -55,10 +55,11 @@ create_or_index_paths(Query *root,
RelOptInfo *rel, List *clauses)
{
List *t_list = NIL;
List *clist;
if (clauses != NIL)
foreach(clist, clauses)
{
CInfo *clausenode = (CInfo *) (lfirst(clauses));
CInfo *clausenode = (CInfo *) (lfirst(clist));
/*
* Check to see if this clause is an 'or' clause, and, if so,
@ -77,8 +78,11 @@ create_or_index_paths(Query *root,
index_list = clausenode->indexids;
foreach(temp, index_list)
{
if (!temp)
if (!lfirst(temp))
{
index_flag = false;
break;
}
}
if (index_flag)
{ /* used to be a lisp every function */
@ -100,8 +104,7 @@ create_or_index_paths(Query *root,
pathnode->path.pathtype = T_IndexScan;
pathnode->path.parent = rel;
pathnode->indexqual =
lcons(clausenode, NIL);
pathnode->indexqual = lcons(clausenode, NIL);
pathnode->indexid = indexids;
pathnode->path.path_cost = cost;
@ -110,9 +113,8 @@ create_or_index_paths(Query *root,
* processing -- JMH, 7/7/92
*/
pathnode->path.locclauseinfo =
set_difference(clauses,
copyObject((Node *)
rel->clauseinfo));
set_difference(copyObject((Node *)rel->clauseinfo),
lcons(clausenode,NIL));
#if 0 /* fix xfunc */
/* add in cost for expensive functions! -- JMH, 7/7/92 */
@ -123,12 +125,8 @@ create_or_index_paths(Query *root,
}
#endif
clausenode->selectivity = (Cost) floatVal(selecs);
t_list =
lcons(pathnode,
create_or_index_paths(root, rel, lnext(clauses)));
t_list = lappend(t_list, pathnode);
}
else
t_list = create_or_index_paths(root, rel, lnext(clauses));
}
}
@ -167,32 +165,28 @@ best_or_subclause_indices(Query *root,
Cost *cost, /* return value */
List **selecs) /* return value */
{
if (subclauses == NIL)
{
*indexids = nreverse(examined_indexids);
*cost = subcost;
*selecs = nreverse(selectivities);
}
else
List *slist;
foreach (slist, subclauses)
{
int best_indexid;
Cost best_cost;
Cost best_selec;
best_or_subclause_index(root, rel, lfirst(subclauses), lfirst(indices),
best_or_subclause_index(root, rel, lfirst(slist), lfirst(indices),
&best_indexid, &best_cost, &best_selec);
examined_indexids = lappendi(examined_indexids, best_indexid);
subcost += best_cost;
selectivities = lappend(selectivities, makeFloat(best_selec));
best_or_subclause_indices(root,
rel,
lnext(subclauses),
lnext(indices),
lconsi(best_indexid, examined_indexids),
subcost + best_cost,
lcons(makeFloat(best_selec), selectivities),
indexids,
cost,
selecs);
indices = lnext(indices);
}
*indexids = examined_indexids;
*cost = subcost;
*selecs = selectivities;
return;
}
@ -219,20 +213,21 @@ best_or_subclause_index(Query *root,
Cost *retCost, /* return value */
Cost *retSelec) /* return value */
{
if (indices != NIL)
List *ilist;
bool first_run = true;
foreach (ilist, indices)
{
RelOptInfo *index = (RelOptInfo *) lfirst(ilist);
Datum value;
int flag = 0;
Cost subcost;
RelOptInfo *index = (RelOptInfo *) lfirst(indices);
AttrNumber attno = (get_leftop(subclause))->varattno;
Oid opno = ((Oper *) subclause->oper)->opno;
bool constant_on_right = non_null((Expr *) get_rightop(subclause));
float npages,
selec;
int subclause_indexid;
Cost subclause_cost;
Cost subclause_selec;
if (constant_on_right)
value = ((Const *) get_rightop(subclause))->constvalue;
@ -242,6 +237,7 @@ best_or_subclause_index(Query *root,
flag = (_SELEC_IS_CONSTANT_ || _SELEC_CONSTANT_RIGHT_);
else
flag = _SELEC_CONSTANT_RIGHT_;
index_selectivity(lfirsti(index->relids),
index->classlist,
lconsi(opno, NIL),
@ -262,26 +258,22 @@ best_or_subclause_index(Query *root,
index->pages,
index->tuples,
false);
best_or_subclause_index(root,
rel,
subclause,
lnext(indices),
&subclause_indexid,
&subclause_cost,
&subclause_selec);
if (subclause_indexid == 0 || subcost < subclause_cost)
if (first_run || subcost < *retCost)
{
*retIndexid = lfirsti(index->relids);
*retCost = subcost;
*retSelec = selec;
first_run = false;
}
else
{
*retIndexid = 0;
*retCost = 0.0;
*retSelec = 0.0;
}
}
/* we didn't get any indexes, so zero return values */
if (first_run)
{
*retIndexid = 0;
*retCost = 0.0;
*retSelec = 0.0;
}
return;
}