Remove 'restrictinfojoinid' field from RestrictInfo nodes.

The only place it was being used was as temporary storage in indxpath.c,
and the logic was wrong: the same restrictinfo node could get chosen to
carry the info for two different joins.  Right fix is to return a second
list of unjoined-relids parallel to the list of clause groups.
This commit is contained in:
Tom Lane 1999-07-25 17:53:27 +00:00
parent ac4913a0dd
commit 8ae29a1d40
4 changed files with 78 additions and 39 deletions

View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.87 1999/07/24 23:21:06 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/nodes/copyfuncs.c,v 1.88 1999/07/25 17:53:27 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1321,7 +1321,6 @@ _copyRestrictInfo(RestrictInfo *from)
Node_Copy(from, newnode, indexids);
Node_Copy(from, newnode, mergejoinorder);
newnode->hashjoinoperator = from->hashjoinoperator;
newnode->restrictinfojoinid = listCopy(from->restrictinfojoinid);
return newnode;
}

View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/nodes/Attic/freefuncs.c,v 1.22 1999/07/17 20:17:06 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/nodes/Attic/freefuncs.c,v 1.23 1999/07/25 17:53:27 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -929,7 +929,6 @@ _freeRestrictInfo(RestrictInfo *node)
freeObject(node->clause);
freeObject(node->indexids);
freeObject(node->mergejoinorder);
freeList(node->restrictinfojoinid);
pfree(node);
}

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.63 1999/07/24 23:21:09 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.64 1999/07/25 17:53:27 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -55,10 +55,11 @@ static bool one_pred_test(Expr *predicate, List *restrictinfo_list);
static bool one_pred_clause_expr_test(Expr *predicate, Node *clause);
static bool one_pred_clause_test(Expr *predicate, Node *clause);
static bool clause_pred_clause_test(Expr *predicate, Node *clause);
static List *indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
List *joininfo_list, List *restrictinfo_list);
static List *index_innerjoin(Query *root, RelOptInfo *rel,
List *clausegroup_list, RelOptInfo *index);
static void indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
List *joininfo_list, List *restrictinfo_list,
List **clausegroups, List **outerrelids);
static List *index_innerjoin(Query *root, RelOptInfo *rel, RelOptInfo *index,
List *clausegroup_list, List *outerrelids_list);
static List *create_index_path_group(Query *root, RelOptInfo *rel, RelOptInfo *index,
List *clausegroup_list, bool join);
static bool match_index_to_operand(int indexkey, Expr *operand,
@ -99,6 +100,7 @@ create_index_paths(Query *root,
RelOptInfo *index = (RelOptInfo *) lfirst(ilist);
List *scanclausegroups;
List *joinclausegroups;
List *joinouterrelids;
/*
* If this is a partial index, we can only use it if it passes
@ -161,9 +163,10 @@ create_index_paths(Query *root,
* mergejoin, or if the index can possibly be used for scanning
* the inner relation of a nestloop join.
*/
joinclausegroups = indexable_joinclauses(rel, index,
joininfo_list,
restrictinfo_list);
indexable_joinclauses(rel, index,
joininfo_list, restrictinfo_list,
&joinclausegroups,
&joinouterrelids);
if (joinclausegroups != NIL)
{
@ -174,9 +177,9 @@ create_index_paths(Query *root,
joinclausegroups,
true));
rel->innerjoin = nconc(rel->innerjoin,
index_innerjoin(root, rel,
index_innerjoin(root, rel, index,
joinclausegroups,
index));
joinouterrelids));
}
}
@ -326,19 +329,23 @@ match_index_orclause(RelOptInfo *rel,
* 'index' is a index on 'rel'.
* 'indexkeys' are the index keys to be matched.
* 'classes' are the classes of the index operators on those keys.
* 'clauses' is the list of available restriction clauses for 'rel'.
* 'restrictinfo_list' is the list of available restriction clauses for 'rel'.
*
* Returns NIL if no clauses can be used with this index.
* Otherwise, a list containing a single sublist is returned (indicating
* to create_index_path_group() that a single IndexPath should be created).
* The sublist is ordered by index key, and contains sublists of clauses
* that can be used with that index key.
* The sublist contains the RestrictInfo nodes for all clauses that can be
* used with this index.
*
* The sublist is ordered by index key (but as far as I can tell, this is
* an implementation artifact of this routine, and is not depended on by
* any user of the returned list --- tgl 7/99).
*
* Note that in a multi-key index, we stop if we find a key that cannot be
* used with any clause. For example, given an index on (A,B,C), we might
* return (((C1 C2) (C3 C4))) if we find that clauses C1 and C2 use column A,
* return ((C1 C2 C3 C4)) if we find that clauses C1 and C2 use column A,
* clauses C3 and C4 use column B, and no clauses use column C. But if no
* clauses match B we will return (((C1 C2))), whether or not there are
* clauses match B we will return ((C1 C2)), whether or not there are
* clauses matching column C, because the executor couldn't use them anyway.
*/
static List *
@ -1108,21 +1115,35 @@ clause_pred_clause_test(Expr *predicate, Node *clause)
* Finds all groups of join clauses from among 'joininfo_list' that can
* be used in conjunction with 'index'.
*
* The first clause in the group is marked as having the other relation
* in the join clause as its outer join relation.
* Each clause group comes from a single joininfo node plus the current
* rel's restrictinfo list. Therefore, every clause in the group references
* the current rel plus the same set of other rels (except for the restrict
* clauses, which only reference the current rel). Therefore, this set
* of clauses could be used as an indexqual if the relation is scanned
* as the inner side of a nestloop join when the outer side contains
* (at least) all those "other rels".
*
* Returns a list of these clause groups.
* XXX Actually, given that we are considering a join that requires an
* outer rel set (A,B,C), we should use all qual clauses that reference
* any subset of these rels, not just the full set or none. This is
* doable with a doubly nested loop over joininfo_list; is it worth it?
*
* Added: restrictinfo_list - list of restriction RestrictInfos. It's to
* support multi-column indices in joins and for cases
* when a key is in both join & restriction clauses. - vadim 03/18/97
* Returns two parallel lists of the same length: the clause groups,
* and the required outer rel set for each one.
*
* 'rel' is the relation for which 'index' is defined
* 'joininfo_list' is the list of JoinInfo nodes for 'rel'
* 'restrictinfo_list' is the list of restriction clauses for 'rel'
* '*clausegroups' receives a list of clause sublists
* '*outerrelids' receives a list of relid lists
*/
static List *
static void
indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
List *joininfo_list, List *restrictinfo_list)
List *joininfo_list, List *restrictinfo_list,
List **clausegroups, List **outerrelids)
{
List *cg_list = NIL;
List *relid_list = NIL;
List *i;
foreach(i, joininfo_list)
@ -1139,15 +1160,32 @@ indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
joininfo->jinfo_restrictinfo,
restrictinfo_list);
/*----------
* This code knows that group_clauses_by_ikey_for_joins() returns
* either NIL or a list containing a single sublist of clauses.
* The line
* cg_list = nconc(cg_list, clausegroups);
* is better read as
* cg_list = lappend(cg_list, lfirst(clausegroups));
* That is, we are appending the only sublist returned by
* group_clauses_by_ikey_for_joins() to the list of clause sublists
* that this routine will return. By using nconc() we recycle
* a cons cell that would be wasted ... whoever wrote this code
* was too clever by half...
*----------
*/
if (clausegroups != NIL)
{
List *clauses = lfirst(clausegroups);
((RestrictInfo *) lfirst(clauses))->restrictinfojoinid = joininfo->unjoined_relids;
cg_list = nconc(cg_list, clausegroups);
relid_list = lappend(relid_list, joininfo->unjoined_relids);
}
}
return cg_list;
/* Make sure above clever code didn't screw up */
Assert(length(cg_list) == length(relid_list));
*clausegroups = cg_list;
*outerrelids = relid_list;
}
/****************************************************************************
@ -1159,15 +1197,17 @@ indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
* Creates index path nodes corresponding to paths to be used as inner
* relations in nestloop joins.
*
* 'clausegroup-list' is a list of list of restrictinfo nodes which can use
* 'rel' is the relation for which 'index' is defined
* 'clausegroup_list' is a list of lists of restrictinfo nodes which can use
* 'index' on their inner relation.
* 'outerrelids_list' is a list of the required outer rels for each group
* of join clauses.
*
* Returns a list of index pathnodes.
*
*/
static List *
index_innerjoin(Query *root, RelOptInfo *rel, List *clausegroup_list,
RelOptInfo *index)
index_innerjoin(Query *root, RelOptInfo *rel, RelOptInfo *index,
List *clausegroup_list, List *outerrelids_list)
{
List *path_list = NIL;
List *i;
@ -1211,7 +1251,8 @@ index_innerjoin(Query *root, RelOptInfo *rel, List *clausegroup_list,
pathnode->indexkeys = index->indexkeys;
pathnode->indexqual = lcons(get_actual_clauses(clausegroup), NIL);
pathnode->path.joinid = ((RestrictInfo *) lfirst(clausegroup))->restrictinfojoinid;
/* joinid saves the rels needed on the outer side of the join */
pathnode->path.joinid = lfirst(outerrelids_list);
pathnode->path.path_cost = cost_index((Oid) lfirsti(index->relids),
(int) temp_pages,
@ -1235,6 +1276,7 @@ index_innerjoin(Query *root, RelOptInfo *rel, List *clausegroup_list,
((Path *) pathnode)->path_cost += xfunc_get_path_cost((Path *) pathnode);
#endif
path_list = lappend(path_list, pathnode);
outerrelids_list = lnext(outerrelids_list);
}
return path_list;
}
@ -1245,7 +1287,7 @@ index_innerjoin(Query *root, RelOptInfo *rel, List *clausegroup_list,
* (restriction or join) that can be used in conjunction with an index.
*
* 'rel' is the relation for which 'index' is defined
* 'clausegroup-list' is the list of clause groups (lists of restrictinfo
* 'clausegroup_list' is the list of clause groups (lists of restrictinfo
* nodes) grouped by mergejoinorder
* 'join' is a flag indicating whether or not the clauses are join
* clauses

View File

@ -6,7 +6,7 @@
*
* Copyright (c) 1994, Regents of the University of California
*
* $Id: relation.h,v 1.35 1999/07/24 23:21:04 tgl Exp $
* $Id: relation.h,v 1.36 1999/07/25 17:53:26 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -242,7 +242,6 @@ typedef struct RestrictInfo
/* hashjoin only */
Oid hashjoinoperator;
Relids restrictinfojoinid;
} RestrictInfo;
typedef struct JoinMethod