From 348bdbce7942324dd19349d4d6f3f7dabae219c3 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 23 Jul 1999 03:34:49 +0000
Subject: [PATCH] Minor code beautification, extensive improvement of comments.
This file was full of obsolete and just plain wrong commentary...
---
src/backend/optimizer/path/indxpath.c | 668 ++++++++++++--------------
1 file changed, 296 insertions(+), 372 deletions(-)
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 2fc7d07060c..c539b1f9051 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -2,13 +2,13 @@
*
* indxpath.c
* Routines to determine which indices are usable for scanning a
- * given relation
+ * given relation, and create IndexPaths accordingly.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.61 1999/07/16 04:59:15 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.62 1999/07/23 03:34:49 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -40,16 +40,15 @@
static void match_index_orclauses(RelOptInfo *rel, RelOptInfo *index, int indexkey,
int xclass, List *restrictinfo_list);
-static bool match_index_to_operand(int indexkey, Expr *operand,
- RelOptInfo *rel, RelOptInfo *index);
static List *match_index_orclause(RelOptInfo *rel, RelOptInfo *index, int indexkey,
int xclass, List *or_clauses, List *other_matching_indices);
static List *group_clauses_by_indexkey(RelOptInfo *rel, RelOptInfo *index,
int *indexkeys, Oid *classes, List *restrictinfo_list);
static List *group_clauses_by_ikey_for_joins(RelOptInfo *rel, RelOptInfo *index,
int *indexkeys, Oid *classes, List *join_cinfo_list, List *restr_cinfo_list);
-static RestrictInfo *match_clause_to_indexkey(RelOptInfo *rel, RelOptInfo *index, int indexkey,
- int xclass, RestrictInfo *restrictInfo, bool join);
+static bool match_clause_to_indexkey(RelOptInfo *rel, RelOptInfo *index,
+ int indexkey, int xclass,
+ Expr *clause, bool join);
static bool pred_test(List *predicate_list, List *restrictinfo_list,
List *joininfo_list);
static bool one_pred_test(Expr *predicate, List *restrictinfo_list);
@@ -62,34 +61,28 @@ static List *index_innerjoin(Query *root, RelOptInfo *rel,
List *clausegroup_list, RelOptInfo *index);
static List *create_index_path_group(Query *root, RelOptInfo *rel, RelOptInfo *index,
List *clausegroup_list, bool join);
-static List *add_index_paths(List *indexpaths, List *new_indexpaths);
+static bool match_index_to_operand(int indexkey, Expr *operand,
+ RelOptInfo *rel, RelOptInfo *index);
static bool function_index_operand(Expr *funcOpnd, RelOptInfo *rel, RelOptInfo *index);
-/* find_index_paths()
- * Finds all possible index paths by determining which indices in the
- * list 'indices' are usable.
- *
- * To be usable, an index must match against either a set of
- * restriction clauses or join clauses.
+/*
+ * create_index_paths()
+ * Generate all interesting index paths for the given relation.
*
- * Note that the current implementation requires that there exist
- * matching clauses for every key in the index (i.e., no partial
- * matches are allowed).
+ * To be considered for an index scan, an index must match one or more
+ * restriction clauses or join clauses from the query's qual condition.
*
- * If an index can't be used with restriction clauses, but its keys
- * match those of the result sort order (according to information stored
- * within 'sortkeys'), then the index is also considered.
+ * Note: an index scan might also be used simply to order the result,
+ * either for use in a mergejoin or to satisfy an ORDER BY request.
+ * That possibility is handled elsewhere.
*
- * 'rel' is the relation entry to which these index paths correspond
- * 'indices' is a list of possible index paths
- * 'restrictinfo_list' is a list of restriction restrictinfo nodes for 'rel'
+ * 'rel' is the relation for which we want to generate index paths
+ * 'indices' is a list of available indexes for 'rel'
+ * 'restrictinfo_list' is a list of restrictinfo nodes for 'rel'
* 'joininfo_list' is a list of joininfo nodes for 'rel'
- * 'sortkeys' is a node describing the result sort order (from
- * (find_sortkeys))
- *
- * Returns a list of index nodes.
*
+ * Returns a list of IndexPath access path descriptors.
*/
List *
create_index_paths(Query *root,
@@ -98,21 +91,18 @@ create_index_paths(Query *root,
List *restrictinfo_list,
List *joininfo_list)
{
- List *scanclausegroups = NIL;
- List *scanpaths = NIL;
- RelOptInfo *index = (RelOptInfo *) NULL;
- List *joinclausegroups = NIL;
- List *joinpaths = NIL;
List *retval = NIL;
List *ilist;
foreach(ilist, indices)
{
- index = (RelOptInfo *) lfirst(ilist);
+ RelOptInfo *index = (RelOptInfo *) lfirst(ilist);
+ List *scanclausegroups;
+ List *joinclausegroups;
/*
- * If this is a partial index, return if it fails the predicate
- * test
+ * If this is a partial index, we can only use it if it passes
+ * the predicate test.
*/
if (index->indpred != NIL)
if (!pred_test(index->indpred, restrictinfo_list, joininfo_list))
@@ -121,7 +111,7 @@ create_index_paths(Query *root,
/*
* 1. Try matching the index against subclauses of an 'or' clause.
* The fields of the restrictinfo nodes are marked with lists of
- * the matching indices. No path are actually created. We
+ * the matching indices. No paths are actually created. We
* currently only look to match the first key. We don't find
* multi-key index cases where an AND matches the first key, and
* the OR matches the second key.
@@ -134,8 +124,8 @@ create_index_paths(Query *root,
/*
* 2. If the keys of this index match any of the available
- * restriction clauses, then create pathnodes corresponding to
- * each group of usable clauses.
+ * restriction clauses, then create a path using those clauses
+ * as indexquals.
*/
scanclausegroups = group_clauses_by_indexkey(rel,
index,
@@ -143,13 +133,13 @@ create_index_paths(Query *root,
index->classlist,
restrictinfo_list);
- scanpaths = NIL;
if (scanclausegroups != NIL)
- scanpaths = create_index_path_group(root,
- rel,
- index,
- scanclausegroups,
- false);
+ retval = nconc(retval,
+ create_index_path_group(root,
+ rel,
+ index,
+ scanclausegroups,
+ false));
/*
* 3. If this index can be used with any join clause, then create
@@ -158,36 +148,31 @@ 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);
- joinpaths = NIL;
+ joinclausegroups = indexable_joinclauses(rel, index,
+ joininfo_list,
+ restrictinfo_list);
if (joinclausegroups != NIL)
{
- joinpaths = create_index_path_group(root, rel,
- index,
- joinclausegroups,
- true);
+ retval = nconc(retval,
+ create_index_path_group(root,
+ rel,
+ index,
+ joinclausegroups,
+ true));
rel->innerjoin = nconc(rel->innerjoin,
index_innerjoin(root, rel,
- joinclausegroups, index));
+ joinclausegroups,
+ index));
}
-
- /*
- * Some sanity checks to make sure that the indexpath is valid.
- */
- if (joinpaths != NULL)
- retval = add_index_paths(joinpaths, retval);
- if (scanpaths != NULL)
- retval = add_index_paths(scanpaths, retval);
}
return retval;
-
}
/****************************************************************************
- * ---- ROUTINES TO MATCH 'OR' CLAUSES ----
+ * ---- ROUTINES TO PROCESS 'OR' CLAUSES ----
****************************************************************************/
@@ -202,12 +187,9 @@ create_index_paths(Query *root,
*
* 'rel' is the node of the relation on which the index is defined.
* 'index' is the index node.
- * 'indexkey' is the (single) key of the index
+ * 'indexkey' is the (single) key of the index that we will consider.
* 'class' is the class of the operator corresponding to 'indexkey'.
* 'restrictinfo_list' is the list of available restriction clauses.
- *
- * Returns nothing.
- *
*/
static void
match_index_orclauses(RelOptInfo *rel,
@@ -216,72 +198,43 @@ match_index_orclauses(RelOptInfo *rel,
int xclass,
List *restrictinfo_list)
{
- RestrictInfo *restrictinfo = (RestrictInfo *) NULL;
- List *i = NIL;
+ List *i;
foreach(i, restrictinfo_list)
{
- restrictinfo = (RestrictInfo *) lfirst(i);
+ RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(i);
+
if (valid_or_clause(restrictinfo))
{
-
/*
* Mark the 'or' clause with a list of indices which match
- * each of its subclauses. The list is generated by adding
- * 'index' to the existing list where appropriate.
+ * each of its subclauses. We add entries to the existing
+ * list, if any.
*/
- restrictinfo->indexids = match_index_orclause(rel, index, indexkey,
- xclass,
- restrictinfo->clause->args,
- restrictinfo->indexids);
+ restrictinfo->indexids =
+ match_index_orclause(rel, index,
+ indexkey, xclass,
+ restrictinfo->clause->args,
+ restrictinfo->indexids);
}
}
}
-/* match_index_to_operand()
- * Generalize test for a match between an existing index's key
- * and the operand on the rhs of a restriction clause. Now check
- * for functional indices as well.
- */
-static bool
-match_index_to_operand(int indexkey,
- Expr *operand,
- RelOptInfo *rel,
- RelOptInfo *index)
-{
- bool result;
-
- /*
- * Normal index.
- */
- if (index->indproc == InvalidOid)
- {
- result = match_indexkey_operand(indexkey, (Var *) operand, rel);
- return result;
- }
-
- /*
- * functional index check
- */
- result = function_index_operand(operand, rel, index);
- return result;
-}
-
/*
* match_index_orclause
* Attempts to match an index against the subclauses of an 'or' clause.
*
* A match means that:
- * (1) the operator within the subclause can be used with one
- * of the index's operator classes, and
- * (2) there is a usable key that matches the variable within a
- * searchable clause.
+ * (1) the operator within the subclause can be used with the
+ * index's specified operator class, and
+ * (2) the variable on one side of the subclause matches the index key.
*
- * 'or_clauses' are the remaining subclauses within the 'or' clause
+ * 'or_clauses' is the list of subclauses within the 'or' clause
* 'other_matching_indices' is the list of information on other indices
* that have already been matched to subclauses within this
* particular 'or' clause (i.e., a list previously generated by
- * this routine)
+ * this routine), or NIL if this routine has not previously been
+ * run for this 'or' clause.
*
* Returns a list of the form ((a b c) (d e f) nil (g h) ...) where
* a,b,c are nodes of indices that match the first subclause in
@@ -296,14 +249,14 @@ match_index_orclause(RelOptInfo *rel,
List *or_clauses,
List *other_matching_indices)
{
- Node *clause = NULL;
- List *matching_indices = other_matching_indices;
- List *index_list = NIL;
+ List *matching_indices;
+ List *index_list;
List *clist;
- /* first time through, we create index list */
+ /* first time through, we create empty list of same length as OR clause */
if (!other_matching_indices)
{
+ matching_indices = NIL;
foreach(clist, or_clauses)
matching_indices = lcons(NIL, matching_indices);
}
@@ -314,22 +267,14 @@ match_index_orclause(RelOptInfo *rel,
foreach(clist, or_clauses)
{
- clause = lfirst(clist);
+ Expr *clause = lfirst(clist);
- if (is_opclause(clause))
+ if (match_clause_to_indexkey(rel, index, indexkey, xclass,
+ clause, false))
{
- Expr *left = (Expr *) get_leftop((Expr *) clause);
- Expr *right = (Expr *) get_rightop((Expr *) clause);
-
- if (left && right &&
- op_class(((Oper *) ((Expr *) clause)->oper)->opno,
- xclass, index->relam) &&
- ((IsA(right, Const) &&
- match_index_to_operand(indexkey, left, rel, index)) ||
- (IsA(left, Const) &&
- match_index_to_operand(indexkey, right, rel, index))))
- lfirst(matching_indices) = lcons(index,
- lfirst(matching_indices));
+ /* OK to add this index to sublist for this subclause */
+ lfirst(matching_indices) = lcons(index,
+ lfirst(matching_indices));
}
matching_indices = lnext(matching_indices);
@@ -358,26 +303,26 @@ match_index_orclause(RelOptInfo *rel,
/*
* group_clauses_by_indexkey
- * Determines whether there are clauses which will match each and every
- * one of the remaining keys of an index.
+ * Generates a list of restriction clauses that can be used with an index.
*
- * 'rel' is the node of the relation corresponding to the index.
- * 'indexkeys' are the remaining index keys to be matched.
+ * 'rel' is the node of the relation itself.
+ * '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 either:
- * (1) the list of available restriction clauses on a single
- * relation, or
- * (2) a list of join clauses between 'rel' and a fixed set of
- * relations,
- * depending on the value of 'join'.
- *
- * NOTE: it works now for restriction clauses only. - vadim 03/18/97
+ * 'clauses' is the list of available restriction clauses for 'rel'.
*
- * Returns all possible groups of clauses that will match (given that
- * one or more clauses can match any of the remaining keys).
- * E.g., if you have clauses A, B, and C, ((A B) (A C)) might be
- * returned for an index with 2 keys.
+ * 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.
*
+ * 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,
+ * 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 matching column C, because the executor couldn't use them anyway.
*/
static List *
group_clauses_by_indexkey(RelOptInfo *rel,
@@ -386,60 +331,61 @@ group_clauses_by_indexkey(RelOptInfo *rel,
Oid *classes,
List *restrictinfo_list)
{
- List *curCinfo = NIL;
- RestrictInfo *matched_clause = (RestrictInfo *) NULL;
- List *clausegroup = NIL;
- int curIndxKey;
- Oid curClass;
+ List *clausegroup_list = NIL;
if (restrictinfo_list == NIL || indexkeys[0] == 0)
return NIL;
do
{
- List *tempgroup = NIL;
-
- curIndxKey = indexkeys[0];
- curClass = classes[0];
+ int curIndxKey = indexkeys[0];
+ Oid curClass = classes[0];
+ List *clausegroup = NIL;
+ List *curCinfo;
foreach(curCinfo, restrictinfo_list)
{
- RestrictInfo *temp = (RestrictInfo *) lfirst(curCinfo);
-
- matched_clause = match_clause_to_indexkey(rel,
- index,
- curIndxKey,
- curClass,
- temp,
- false);
- if (!matched_clause)
- continue;
-
- tempgroup = lappend(tempgroup, matched_clause);
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(curCinfo);
+
+ if (match_clause_to_indexkey(rel,
+ index,
+ curIndxKey,
+ curClass,
+ rinfo->clause,
+ false))
+ clausegroup = lappend(clausegroup, rinfo);
}
- if (tempgroup == NIL)
+
+ /* If no clauses match this key, we're done; we don't want to
+ * look at keys to its right.
+ */
+ if (clausegroup == NIL)
break;
- clausegroup = nconc(clausegroup, tempgroup);
+ clausegroup_list = nconc(clausegroup_list, clausegroup);
indexkeys++;
classes++;
} while (!DoneMatchingIndexKeys(indexkeys, index));
- /* clausegroup holds all matched clauses ordered by indexkeys */
-
- if (clausegroup != NIL)
- return lcons(clausegroup, NIL);
+ /* clausegroup_list holds all matched clauses ordered by indexkeys */
+ if (clausegroup_list != NIL)
+ return lcons(clausegroup_list, NIL);
return NIL;
}
/*
* group_clauses_by_ikey_for_joins
- * special edition of group_clauses_by_indexkey - will
- * match join & restriction clauses. See comment in indexable_joinclauses.
- * - vadim 03/18/97
+ * Generates a list of join clauses that can be used with an index.
*
+ * This is much like group_clauses_by_indexkey(), but we consider both
+ * join and restriction clauses. For each indexkey in the index, we
+ * accept both join and restriction clauses that match it (since both
+ * will make useful indexquals if the index is being used to scan the
+ * inner side of a join). But there must be at least one matching
+ * join clause, or we return NIL indicating that this index isn't useful
+ * for joining.
*/
static List *
group_clauses_by_ikey_for_joins(RelOptInfo *rel,
@@ -449,11 +395,7 @@ group_clauses_by_ikey_for_joins(RelOptInfo *rel,
List *join_cinfo_list,
List *restr_cinfo_list)
{
- List *curCinfo = NIL;
- RestrictInfo *matched_clause = (RestrictInfo *) NULL;
- List *clausegroup = NIL;
- int curIndxKey;
- Oid curClass;
+ List *clausegroup_list = NIL;
bool jfound = false;
if (join_cinfo_list == NIL || indexkeys[0] == 0)
@@ -461,150 +403,146 @@ group_clauses_by_ikey_for_joins(RelOptInfo *rel,
do
{
- List *tempgroup = NIL;
-
- curIndxKey = indexkeys[0];
- curClass = classes[0];
+ int curIndxKey = indexkeys[0];
+ Oid curClass = classes[0];
+ List *clausegroup = NIL;
+ List *curCinfo;
foreach(curCinfo, join_cinfo_list)
{
- RestrictInfo *temp = (RestrictInfo *) lfirst(curCinfo);
-
- matched_clause = match_clause_to_indexkey(rel,
- index,
- curIndxKey,
- curClass,
- temp,
- true);
- if (!matched_clause)
- continue;
-
- tempgroup = lappend(tempgroup, matched_clause);
- jfound = true;
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(curCinfo);
+
+ if (match_clause_to_indexkey(rel,
+ index,
+ curIndxKey,
+ curClass,
+ rinfo->clause,
+ true))
+ {
+ clausegroup = lappend(clausegroup, rinfo);
+ jfound = true;
+ }
}
foreach(curCinfo, restr_cinfo_list)
{
- RestrictInfo *temp = (RestrictInfo *) lfirst(curCinfo);
-
- matched_clause = match_clause_to_indexkey(rel,
- index,
- curIndxKey,
- curClass,
- temp,
- false);
- if (!matched_clause)
- continue;
-
- tempgroup = lappend(tempgroup, matched_clause);
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(curCinfo);
+
+ if (match_clause_to_indexkey(rel,
+ index,
+ curIndxKey,
+ curClass,
+ rinfo->clause,
+ false))
+ clausegroup = lappend(clausegroup, rinfo);
}
- if (tempgroup == NIL)
+
+ /* If no clauses match this key, we're done; we don't want to
+ * look at keys to its right.
+ */
+ if (clausegroup == NIL)
break;
- clausegroup = nconc(clausegroup, tempgroup);
+ clausegroup_list = nconc(clausegroup_list, clausegroup);
indexkeys++;
classes++;
} while (!DoneMatchingIndexKeys(indexkeys, index));
- /* clausegroup holds all matched clauses ordered by indexkeys */
+ /* clausegroup_list holds all matched clauses ordered by indexkeys */
- if (clausegroup != NIL)
+ if (clausegroup_list != NIL)
{
-
/*
- * if no one join clause was matched then there ain't clauses for
+ * if no join clause was matched then there ain't clauses for
* joins at all.
*/
if (!jfound)
{
- freeList(clausegroup);
+ freeList(clausegroup_list);
return NIL;
}
- return lcons(clausegroup, NIL);
+ return lcons(clausegroup_list, NIL);
}
return NIL;
}
-/*
- * IndexScanableClause () MACRO
- *
- * Generalize condition on which we match a clause with an index.
- * Now we can match with functional indices.
- */
-#define IndexScanableOperand(opnd, indkeys, rel, index) \
- ((index->indproc == InvalidOid) ? \
- match_indexkey_operand(indkeys, opnd, rel) : \
- function_index_operand((Expr*)opnd,rel,index))
/*
- * There was
- * equal_indexkey_var(indkeys,opnd) : \
- * above, and now
- * match_indexkey_operand(indkeys, opnd, rel) : \
- * - vadim 01/22/97
- */
-
-/* match_clause_to_indexkey()
- * Finds the first of a relation's available restriction clauses that
- * matches a key of an index.
+ * match_clause_to_indexkey()
+ * Determines whether a restriction or join clause matches
+ * a key of an index.
*
* To match, the clause must:
- * (1) be in the form (op var const) if the clause is a single-
- * relation clause, and
+ * (1) be in the form (var op const) for a restriction clause,
+ * or (var op var) for a join clause, where the var or one
+ * of the vars matches the index key; and
* (2) contain an operator which is in the same class as the index
- * operator for this key.
+ * operator for this key.
*
- * If the clause being matched is a join clause, then 'join' is t.
+ * In the restriction case, we can cope with (const op var) by commuting
+ * the clause to (var op const), if there is a commutator operator.
+ * XXX why do we bother to commute? The executor doesn't care!!
*
- * Returns a single restrictinfo node corresponding to the matching
- * clause.
+ * In the join case, later code will try to commute the clause if needed
+ * to put the inner relation's var on the right. We have no idea here
+ * which relation might wind up on the inside, so we just accept
+ * a match for either var.
+ * XXX is this right? We are making a list for this relation to
+ * be an inner join relation, so if there is any commuting then
+ * this rel must be on the right. But again, it's not really clear
+ * that we have to commute at all!
*
- * NOTE: returns nil if clause is an or_clause.
+ * 'rel' is the relation of interest.
+ * 'index' is an index on 'rel'.
+ * 'indexkey' is a key of 'index'.
+ * 'xclass' is the corresponding operator class.
+ * 'clause' is the clause to be tested.
+ * 'join' is true if we are considering this clause for joins.
*
+ * Returns true if the clause can be used with this index key.
+ *
+ * NOTE: returns false if clause is an or_clause; that's handled elsewhere.
*/
-static RestrictInfo *
+static bool
match_clause_to_indexkey(RelOptInfo *rel,
RelOptInfo *index,
int indexkey,
int xclass,
- RestrictInfo *restrictInfo,
+ Expr *clause,
bool join)
{
- Expr *clause = restrictInfo->clause;
+ bool isIndexable = false;
Var *leftop,
*rightop;
- Oid join_op = InvalidOid;
- Oid restrict_op = InvalidOid;
- bool isIndexable = false;
-
- if (or_clause((Node *) clause) ||
- not_clause((Node *) clause) || single_node((Node *) clause))
- return (RestrictInfo *) NULL;
+ if (! is_opclause((Node *) clause))
+ return false;
leftop = get_leftop(clause);
rightop = get_rightop(clause);
+ if (! leftop || ! rightop)
+ return false;
- /*
- * If this is not a join clause, check for clauses of the form:
- * (operator var/func constant) and (operator constant var/func)
- */
if (!join)
{
+ /*
+ * Not considering joins, so check for clauses of the form:
+ * (var/func operator constant) and (constant operator var/func)
+ */
+ Oid restrict_op = InvalidOid;
/*
* Check for standard s-argable clause
*/
- if ((rightop && IsA(rightop, Const)) ||
- (rightop && IsA(rightop, Param)))
+ if (IsA(rightop, Const) || IsA(rightop, Param))
{
restrict_op = ((Oper *) ((Expr *) clause)->oper)->opno;
isIndexable = (op_class(restrict_op, xclass, index->relam) &&
- IndexScanableOperand(leftop,
- indexkey,
- rel,
- index));
+ match_index_to_operand(indexkey,
+ (Expr *) leftop,
+ rel,
+ index));
#ifndef IGNORE_BINARY_COMPATIBLE_INDICES
@@ -614,11 +552,8 @@ match_clause_to_indexkey(RelOptInfo *rel,
*/
if (!isIndexable)
{
- Oid ltype;
- Oid rtype;
-
- ltype = exprType((Node *) leftop);
- rtype = exprType((Node *) rightop);
+ Oid ltype = exprType((Node *) leftop);
+ Oid rtype = exprType((Node *) rightop);
/*
* make sure we have two different binary-compatible
@@ -637,15 +572,16 @@ match_clause_to_indexkey(RelOptInfo *rel,
newop = NULL;
/* actually have a different operator to try? */
- if (HeapTupleIsValid(newop) && (oprid(newop) != restrict_op))
+ if (HeapTupleIsValid(newop) &&
+ (oprid(newop) != restrict_op))
{
restrict_op = oprid(newop);
isIndexable = (op_class(restrict_op, xclass, index->relam) &&
- IndexScanableOperand(leftop,
- indexkey,
- rel,
- index));
+ match_index_to_operand(indexkey,
+ (Expr *) leftop,
+ rel,
+ index));
if (isIndexable)
((Oper *) ((Expr *) clause)->oper)->opno = restrict_op;
@@ -658,15 +594,16 @@ match_clause_to_indexkey(RelOptInfo *rel,
/*
* Must try to commute the clause to standard s-arg format.
*/
- else if ((leftop && IsA(leftop, Const)) ||
- (leftop && IsA(leftop, Param)))
+ else if (IsA(leftop, Const) || IsA(leftop, Param))
{
restrict_op = get_commutator(((Oper *) ((Expr *) clause)->oper)->opno);
isIndexable = ((restrict_op != InvalidOid) &&
op_class(restrict_op, xclass, index->relam) &&
- IndexScanableOperand(rightop,
- indexkey, rel, index));
+ match_index_to_operand(indexkey,
+ (Expr *) rightop,
+ rel,
+ index));
#ifndef IGNORE_BINARY_COMPATIBLE_INDICES
if (!isIndexable)
@@ -697,10 +634,10 @@ match_clause_to_indexkey(RelOptInfo *rel,
isIndexable = ((restrict_op != InvalidOid) &&
op_class(restrict_op, xclass, index->relam) &&
- IndexScanableOperand(rightop,
- indexkey,
- rel,
- index));
+ match_index_to_operand(indexkey,
+ (Expr *) rightop,
+ rel,
+ index));
if (isIndexable)
((Oper *) ((Expr *) clause)->oper)->opno = oprid(newop);
@@ -720,42 +657,30 @@ match_clause_to_indexkey(RelOptInfo *rel,
}
}
}
-
- /*
- * Check for an indexable scan on one of the join relations. clause is
- * of the form (operator var/func var/func)
- */
else
{
- if (rightop
- && match_index_to_operand(indexkey, (Expr *) rightop, rel, index))
- {
- join_op = get_commutator(((Oper *) ((Expr *) clause)->oper)->opno);
+ /*
+ * Check for an indexable scan on one of the join relations.
+ * clause is of the form (operator var/func var/func)
+ * XXX this does not seem right. Should check other side
+ * looks like var/func? do we really want to only consider
+ * this rel on lefthand side??
+ */
+ Oid join_op = InvalidOid;
- }
- else if (leftop
- && match_index_to_operand(indexkey,
- (Expr *) leftop, rel, index))
+ if (match_index_to_operand(indexkey, (Expr *) leftop,
+ rel, index))
join_op = ((Oper *) ((Expr *) clause)->oper)->opno;
+ else if (match_index_to_operand(indexkey, (Expr *) rightop,
+ rel, index))
+ join_op = get_commutator(((Oper *) ((Expr *) clause)->oper)->opno);
if (join_op && op_class(join_op, xclass, index->relam) &&
is_joinable((Node *) clause))
- {
isIndexable = true;
-
- /*
- * If we're using the operand's commutator we must commute the
- * clause.
- */
- if (join_op != ((Oper *) ((Expr *) clause)->oper)->opno)
- CommuteClause((Node *) clause);
- }
}
- if (isIndexable)
- return restrictInfo;
-
- return NULL;
+ return isIndexable;
}
/****************************************************************************
@@ -960,7 +885,8 @@ one_pred_clause_test(Expr *predicate, Node *clause)
* this test should always be considered false.
*/
-StrategyNumber BT_implic_table[BTMaxStrategyNumber][BTMaxStrategyNumber] = {
+static StrategyNumber
+BT_implic_table[BTMaxStrategyNumber][BTMaxStrategyNumber] = {
{2, 2, 0, 0, 0},
{1, 2, 0, 0, 0},
{1, 2, 3, 4, 5},
@@ -1179,14 +1105,13 @@ static List *
indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
List *joininfo_list, List *restrictinfo_list)
{
- JoinInfo *joininfo = (JoinInfo *) NULL;
List *cg_list = NIL;
- List *i = NIL;
- List *clausegroups = NIL;
+ List *i;
foreach(i, joininfo_list)
{
- joininfo = (JoinInfo *) lfirst(i);
+ JoinInfo *joininfo = (JoinInfo *) lfirst(i);
+ List *clausegroups;
if (joininfo->jinfo_restrictinfo == NIL)
continue;
@@ -1202,8 +1127,8 @@ indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
List *clauses = lfirst(clausegroups);
((RestrictInfo *) lfirst(clauses))->restrictinfojoinid = joininfo->unjoined_relids;
+ cg_list = nconc(cg_list, clausegroups);
}
- cg_list = nconc(cg_list, clausegroups);
}
return cg_list;
}
@@ -1212,30 +1137,6 @@ indexable_joinclauses(RelOptInfo *rel, RelOptInfo *index,
* ---- PATH CREATION UTILITIES ----
****************************************************************************/
-/*
- * extract_restrict_clauses -
- * the list of clause info contains join clauses and restriction clauses.
- * This routine returns the restriction clauses only.
- */
-#ifdef NOT_USED
-static List *
-extract_restrict_clauses(List *clausegroup)
-{
- List *restrict_cls = NIL;
- List *l;
-
- foreach(l, clausegroup)
- {
- RestrictInfo *cinfo = lfirst(l);
-
- if (!is_joinable((Node *) cinfo->clause))
- restrict_cls = lappend(restrict_cls, cinfo);
- }
- return restrict_cls;
-}
-
-#endif
-
/*
* index_innerjoin
* Creates index path nodes corresponding to paths to be used as inner
@@ -1251,22 +1152,19 @@ static List *
index_innerjoin(Query *root, RelOptInfo *rel, List *clausegroup_list,
RelOptInfo *index)
{
- List *clausegroup = NIL;
- List *cg_list = NIL;
- List *i = NIL;
- IndexPath *pathnode = (IndexPath *) NULL;
- Cost temp_selec;
- float temp_pages;
+ List *path_list = NIL;
+ List *i;
foreach(i, clausegroup_list)
{
+ List *clausegroup = lfirst(i);
+ IndexPath *pathnode = makeNode(IndexPath);
+ Cost temp_selec;
+ float temp_pages;
List *attnos,
*values,
*flags;
- clausegroup = lfirst(i);
- pathnode = makeNode(IndexPath);
-
get_joinvars(lfirsti(rel->relids), clausegroup,
&attnos, &values, &flags);
index_selectivity(lfirsti(index->relids),
@@ -1315,9 +1213,9 @@ index_innerjoin(Query *root, RelOptInfo *rel, List *clausegroup_list,
if (XfuncMode != XFUNC_OFF)
((Path *) pathnode)->path_cost += xfunc_get_path_cost((Path *) pathnode);
#endif
- cg_list = lappend(cg_list, pathnode);
+ path_list = lappend(path_list, pathnode);
}
- return cg_list;
+ return path_list;
}
/*
@@ -1341,41 +1239,69 @@ create_index_path_group(Query *root,
List *clausegroup_list,
bool join)
{
- List *clausegroup = NIL;
- List *ip_list = NIL;
- List *i = NIL;
- List *j = NIL;
- IndexPath *temp_path;
+ List *path_list = NIL;
+ List *i;
foreach(i, clausegroup_list)
{
- RestrictInfo *restrictinfo;
- bool temp = true;
-
- clausegroup = lfirst(i);
+ List *clausegroup = lfirst(i);
+ bool usable = true;
- foreach(j, clausegroup)
+ if (join)
{
- restrictinfo = (RestrictInfo *) lfirst(j);
- if (!(is_joinable((Node *) restrictinfo->clause) &&
- equal_path_merge_ordering(index->ordering,
- restrictinfo->mergejoinorder)))
- temp = false;
+ List *j;
+
+ foreach(j, clausegroup)
+ {
+ RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(j);
+ if (!(is_joinable((Node *) restrictinfo->clause) &&
+ equal_path_merge_ordering(index->ordering,
+ restrictinfo->mergejoinorder)))
+ {
+ usable = false;
+ break;
+ }
+ }
}
- if (!join || temp)
- { /* restriction, ordering scan */
- temp_path = create_index_path(root, rel, index, clausegroup, join);
- ip_list = lappend(ip_list, temp_path);
+ if (usable)
+ {
+ path_list = lappend(path_list,
+ create_index_path(root, rel, index,
+ clausegroup, join));
}
}
- return ip_list;
+ return path_list;
}
-static List *
-add_index_paths(List *indexpaths, List *new_indexpaths)
+/****************************************************************************
+ * ---- ROUTINES TO CHECK OPERANDS ----
+ ****************************************************************************/
+
+/*
+ * match_index_to_operand()
+ * Generalized test for a match between an index's key
+ * and the operand on one side of a restriction or join clause.
+ * Now check for functional indices as well.
+ */
+static bool
+match_index_to_operand(int indexkey,
+ Expr *operand,
+ RelOptInfo *rel,
+ RelOptInfo *index)
{
- return nconc(indexpaths, new_indexpaths);
+ if (index->indproc == InvalidOid)
+ {
+ /*
+ * Normal index.
+ */
+ return match_indexkey_operand(indexkey, (Var *) operand, rel);
+ }
+
+ /*
+ * functional index check
+ */
+ return function_index_operand(operand, rel, index);
}
static bool
@@ -1408,7 +1334,6 @@ function_index_operand(Expr *funcOpnd, RelOptInfo *rel, RelOptInfo *index)
* refer to the right relatiion. 2. the args have the right attr.
* numbers in the right order.
*
- *
* Check all args refer to the correct relation (i.e. the one with the
* functional index defined on it (rel). To do this we can simply
* compare range table entry numbers, they must be the same.
@@ -1425,7 +1350,6 @@ function_index_operand(Expr *funcOpnd, RelOptInfo *rel, RelOptInfo *index)
i = 0;
foreach(arg, funcargs)
{
-
if (indexKeys[i] == 0)
return false;
--
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