/*-------------------------------------------------------------------------
*
* indxpath.c
- * Routines to determine which indices are usable for scanning a
- * given relation, and create IndexPaths accordingly.
+ * Routines to determine which indexes are usable for scanning a
+ * given relation, and create Paths accordingly.
*
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/path/indxpath.c,v 1.131 2003/01/15 19:35:39 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.190 2005/09/24 22:54:36 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include <math.h>
-#include "access/heapam.h"
-#include "access/nbtree.h"
-#include "catalog/catname.h"
-#include "catalog/pg_amop.h"
-#include "catalog/pg_namespace.h"
+#include "access/skey.h"
+#include "catalog/pg_opclass.h"
#include "catalog/pg_operator.h"
-#include "executor/executor.h"
+#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
-#include "nodes/nodeFuncs.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/pathnode.h"
#include "optimizer/paths.h"
+#include "optimizer/predtest.h"
#include "optimizer/restrictinfo.h"
-#include "optimizer/var.h"
-#include "parser/parse_coerce.h"
-#include "parser/parse_expr.h"
-#include "parser/parse_oper.h"
-#include "rewrite/rewriteManip.h"
#include "utils/builtins.h"
-#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
+#include "utils/memutils.h"
+#include "utils/pg_locale.h"
#include "utils/selfuncs.h"
-#include "utils/syscache.h"
/*
* DoneMatchingIndexKeys() - MACRO
- *
- * Formerly this looked at indexkeys, but that's the wrong thing for a
- * functional index.
*/
-#define DoneMatchingIndexKeys(indexkeys, classes) \
- (classes[0] == InvalidOid)
+#define DoneMatchingIndexKeys(classes) (classes[0] == InvalidOid)
#define is_indexable_operator(clause,opclass,indexkey_on_left) \
(indexable_operator(clause,opclass,indexkey_on_left) != InvalidOid)
-
-static void match_index_orclauses(RelOptInfo *rel, IndexOptInfo *index,
- List *restrictinfo_list);
-static List *match_index_orclause(RelOptInfo *rel, IndexOptInfo *index,
- List *or_clauses,
- List *other_matching_indices);
-static bool match_or_subclause_to_indexkey(RelOptInfo *rel,
- IndexOptInfo *index,
- Expr *clause);
-static List *group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index);
-static List *group_clauses_by_indexkey_for_join(RelOptInfo *rel,
- IndexOptInfo *index,
- Relids outer_relids,
- bool isouterjoin);
-static bool match_clause_to_indexkey(RelOptInfo *rel, IndexOptInfo *index,
- int indexkey, Oid opclass, Expr *clause);
-static bool match_join_clause_to_indexkey(RelOptInfo *rel, IndexOptInfo *index,
- int indexkey, Oid opclass, Expr *clause);
+#define IsBooleanOpclass(opclass) \
+ ((opclass) == BOOL_BTREE_OPS_OID || (opclass) == BOOL_HASH_OPS_OID)
+
+
+static List *find_usable_indexes(PlannerInfo *root, RelOptInfo *rel,
+ List *clauses, List *outer_clauses,
+ bool istoplevel, bool isjoininner,
+ Relids outer_relids);
+static Path *choose_bitmap_and(PlannerInfo *root, RelOptInfo *rel, List *paths);
+static int bitmap_path_comparator(const void *a, const void *b);
+static Cost bitmap_and_cost_est(PlannerInfo *root, RelOptInfo *rel, List *paths);
+static bool match_clause_to_indexcol(IndexOptInfo *index,
+ int indexcol, Oid opclass,
+ RestrictInfo *rinfo,
+ Relids outer_relids);
static Oid indexable_operator(Expr *clause, Oid opclass,
bool indexkey_on_left);
-static bool pred_test(List *predicate_list, List *restrictinfo_list,
- List *joininfo_list, int relvarno);
-static bool pred_test_restrict_list(Expr *predicate, List *restrictinfo_list);
-static bool pred_test_recurse_clause(Expr *predicate, Node *clause);
-static bool pred_test_recurse_pred(Expr *predicate, Node *clause);
-static bool pred_test_simple_clause(Expr *predicate, Node *clause);
-static Relids indexable_outerrelids(RelOptInfo *rel, IndexOptInfo *index);
-static Path *make_innerjoin_index_path(Query *root,
- RelOptInfo *rel, IndexOptInfo *index,
- List *clausegroup);
-static bool match_index_to_operand(int indexkey, Node *operand,
- RelOptInfo *rel, IndexOptInfo *index);
-static bool function_index_operand(Expr *funcOpnd, RelOptInfo *rel,
- IndexOptInfo *index);
+static Relids indexable_outerrelids(RelOptInfo *rel);
+static bool matches_any_index(RestrictInfo *rinfo, RelOptInfo *rel,
+ Relids outer_relids);
+static List *find_clauses_for_join(PlannerInfo *root, RelOptInfo *rel,
+ Relids outer_relids, bool isouterjoin);
+static ScanDirection match_variant_ordering(PlannerInfo *root,
+ IndexOptInfo *index,
+ List *restrictclauses);
+static List *identify_ignorable_ordering_cols(PlannerInfo *root,
+ IndexOptInfo *index,
+ List *restrictclauses);
+static bool match_index_to_query_keys(PlannerInfo *root,
+ IndexOptInfo *index,
+ ScanDirection indexscandir,
+ List *ignorables);
+static bool match_boolean_index_clause(Node *clause, int indexcol,
+ IndexOptInfo *index);
static bool match_special_index_operator(Expr *clause, Oid opclass,
bool indexkey_on_left);
-static List *prefix_quals(Node *leftop, Oid expr_op,
+static Expr *expand_boolean_index_clause(Node *clause, int indexcol,
+ IndexOptInfo *index);
+static List *expand_indexqual_condition(RestrictInfo *rinfo, Oid opclass);
+static List *prefix_quals(Node *leftop, Oid opclass,
Const *prefix, Pattern_Prefix_Status pstatus);
-static List *network_prefix_quals(Node *leftop, Oid expr_op, Datum rightop);
-static Oid find_operator(const char *opname, Oid datatype);
+static List *network_prefix_quals(Node *leftop, Oid expr_op, Oid opclass,
+ Datum rightop);
static Datum string_to_datum(const char *str, Oid datatype);
static Const *string_to_const(const char *str, Oid datatype);
*
* 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,
- * or match the query's ORDER BY condition.
+ * or match the query's ORDER BY condition, or have a predicate that
+ * matches the query's qual condition.
*
* There are two basic kinds of index scans. A "plain" index scan uses
* only restriction clauses (possibly none at all) in its indexqual,
* scan this routine deems potentially interesting for the current query.
*
* We also determine the set of other relids that participate in join
- * clauses that could be used with each index. The actually best innerjoin
+ * clauses that could be used with each index. The actually best innerjoin
* path will be generated for each outer relation later on, but knowing the
* set of potential otherrels allows us to identify equivalent outer relations
* and avoid repeated computation.
*
* 'rel' is the relation for which we want to generate index paths
+ *
+ * Note: check_partial_indexes() must have been run previously.
*/
void
-create_index_paths(Query *root, RelOptInfo *rel)
+create_index_paths(PlannerInfo *root, RelOptInfo *rel)
{
- List *restrictinfo_list = rel->baserestrictinfo;
- List *joininfo_list = rel->joininfo;
- Relids all_join_outerrelids = NIL;
- List *ilist;
+ List *indexpaths;
+ List *bitindexpaths;
+ ListCell *l;
+
+ /* Skip the whole mess if no indexes */
+ if (rel->indexlist == NIL)
+ {
+ rel->index_outer_relids = NULL;
+ return;
+ }
+
+ /*
+ * Examine join clauses to see which ones are potentially usable with
+ * indexes of this rel, and generate the set of all other relids that
+ * participate in such join clauses. We'll use this set later to
+ * recognize outer rels that are equivalent for joining purposes.
+ */
+ rel->index_outer_relids = indexable_outerrelids(rel);
+
+ /*
+ * Find all the index paths that are directly usable for this relation
+ * (ie, are valid without considering OR or JOIN clauses).
+ */
+ indexpaths = find_usable_indexes(root, rel,
+ rel->baserestrictinfo, NIL,
+ true, false, NULL);
+
+ /*
+ * We can submit them all to add_path. (This generates access paths for
+ * plain IndexScan plans.) However, for the next step we will only want
+ * the ones that have some selectivity; we must discard anything that was
+ * generated solely for ordering purposes.
+ */
+ bitindexpaths = NIL;
+ foreach(l, indexpaths)
+ {
+ IndexPath *ipath = (IndexPath *) lfirst(l);
+
+ add_path(rel, (Path *) ipath);
+
+ if (ipath->indexselectivity < 1.0 &&
+ !ScanDirectionIsBackward(ipath->indexscandir))
+ bitindexpaths = lappend(bitindexpaths, ipath);
+ }
+
+ /*
+ * Generate BitmapOrPaths for any suitable OR-clauses present in the
+ * restriction list. Add these to bitindexpaths.
+ */
+ indexpaths = generate_bitmap_or_paths(root, rel,
+ rel->baserestrictinfo, NIL,
+ false, NULL);
+ bitindexpaths = list_concat(bitindexpaths, indexpaths);
+
+ /*
+ * If we found anything usable, generate a BitmapHeapPath for the
+ * most promising combination of bitmap index paths.
+ */
+ if (bitindexpaths != NIL)
+ {
+ Path *bitmapqual;
+ BitmapHeapPath *bpath;
+
+ bitmapqual = choose_bitmap_and(root, rel, bitindexpaths);
+ bpath = create_bitmap_heap_path(root, rel, bitmapqual, false);
+ add_path(rel, (Path *) bpath);
+ }
+}
+
+
+/*----------
+ * find_usable_indexes
+ * Given a list of restriction clauses, find all the potentially usable
+ * indexes for the given relation, and return a list of IndexPaths.
+ *
+ * The caller actually supplies two lists of restriction clauses: some
+ * "current" ones and some "outer" ones. Both lists can be used freely
+ * to match keys of the index, but an index must use at least one of the
+ * "current" clauses to be considered usable. The motivation for this is
+ * examples like
+ * WHERE (x = 42) AND (... OR (y = 52 AND z = 77) OR ....)
+ * While we are considering the y/z subclause of the OR, we can use "x = 42"
+ * as one of the available index conditions; but we shouldn't match the
+ * subclause to any index on x alone, because such a Path would already have
+ * been generated at the upper level. So we could use an index on x,y,z
+ * or an index on x,y for the OR subclause, but not an index on just x.
+ * When dealing with a partial index, a match of the index predicate to
+ * one of the "current" clauses also makes the index usable.
+ *
+ * If istoplevel is true (indicating we are considering the top level of a
+ * rel's restriction clauses), we will include indexes in the result that
+ * have an interesting sort order, even if they have no matching restriction
+ * clauses.
+ *
+ * 'rel' is the relation for which we want to generate index paths
+ * 'clauses' is the current list of clauses (RestrictInfo nodes)
+ * 'outer_clauses' is the list of additional upper-level clauses
+ * 'istoplevel' is true if clauses are the rel's top-level restriction list
+ * (outer_clauses must be NIL when this is true)
+ * 'isjoininner' is true if forming an inner indexscan (so some of the
+ * given clauses are join clauses)
+ * 'outer_relids' identifies the outer side of the join (pass NULL
+ * if not isjoininner)
+ *
+ * Note: check_partial_indexes() must have been run previously.
+ *----------
+ */
+static List *
+find_usable_indexes(PlannerInfo *root, RelOptInfo *rel,
+ List *clauses, List *outer_clauses,
+ bool istoplevel, bool isjoininner,
+ Relids outer_relids)
+{
+ List *result = NIL;
+ List *all_clauses = NIL; /* not computed till needed */
+ ListCell *ilist;
foreach(ilist, rel->indexlist)
{
IndexOptInfo *index = (IndexOptInfo *) lfirst(ilist);
+ IndexPath *ipath;
List *restrictclauses;
List *index_pathkeys;
List *useful_pathkeys;
+ bool useful_predicate;
+ bool found_clause;
bool index_is_ordered;
- Relids join_outerrelids;
/*
- * If this is a partial index, we can only use it if it passes the
- * predicate test.
+ * Ignore partial indexes that do not match the query. If a partial
+ * index is marked predOK then we know it's OK; otherwise, if we
+ * are at top level we know it's not OK (since predOK is exactly
+ * whether its predicate could be proven from the toplevel clauses).
+ * Otherwise, we have to test whether the added clauses are
+ * sufficient to imply the predicate. If so, we could use
+ * the index in the current context.
+ *
+ * We set useful_predicate to true iff the predicate was proven
+ * using the current set of clauses. This is needed to prevent
+ * matching a predOK index to an arm of an OR, which would be
+ * a legal but pointlessly inefficient plan. (A better plan will
+ * be generated by just scanning the predOK index alone, no OR.)
*/
+ useful_predicate = false;
if (index->indpred != NIL)
- if (!pred_test(index->indpred, restrictinfo_list, joininfo_list,
- lfirsti(rel->relids)))
- continue;
+ {
+ if (index->predOK)
+ {
+ if (istoplevel)
+ {
+ /* we know predicate was proven from these clauses */
+ useful_predicate = true;
+ }
+ }
+ else
+ {
+ if (istoplevel)
+ continue; /* no point in trying to prove it */
- /*
- * 1. Try matching the index against subclauses of restriction
- * 'or' clauses (ie, 'or' clauses that reference only this
- * relation). The restrictinfo nodes for the 'or' clauses are
- * marked with lists of the matching indices. No paths are
- * actually created now; that will be done in orindxpath.c after
- * all indexes for the rel have been examined. (We need to do it
- * that way because we can potentially use a different index for
- * each subclause of an 'or', so we can't build a path for an 'or'
- * clause until all indexes have been matched against it.)
- *
- * We don't even think about special handling of 'or' clauses that
- * involve more than one relation (ie, are join clauses). Can we
- * do anything useful with those?
- */
- match_index_orclauses(rel, index, restrictinfo_list);
+ /* Form all_clauses if not done already */
+ if (all_clauses == NIL)
+ all_clauses = list_concat(list_copy(clauses),
+ outer_clauses);
- /*
- * 2. Match the index against non-'or' restriction clauses.
- */
- restrictclauses = group_clauses_by_indexkey(rel, index);
+ if (!predicate_implied_by(index->indpred, all_clauses))
+ continue; /* can't use it at all */
+
+ if (!predicate_implied_by(index->indpred, outer_clauses))
+ useful_predicate = true;
+ }
+ }
/*
- * 3. Compute pathkeys describing index's ordering, if any, then
- * see how many of them are actually useful for this query.
+ * 1. Match the index against the available restriction clauses.
+ * found_clause is set true only if at least one of the current
+ * clauses was used.
*/
- index_pathkeys = build_index_pathkeys(root, rel, index,
- ForwardScanDirection);
- index_is_ordered = (index_pathkeys != NIL);
- useful_pathkeys = truncate_useless_pathkeys(root, rel,
- index_pathkeys);
+ restrictclauses = group_clauses_by_indexkey(index,
+ clauses,
+ outer_clauses,
+ outer_relids,
+ &found_clause);
/*
- * 4. Generate an indexscan path if there are relevant restriction
- * clauses OR the index ordering is potentially useful for later
- * merging or final output ordering.
- *
- * If there is a predicate, consider it anyway since the index
- * predicate has already been found to match the query. The
- * selectivity of the predicate might alone make the index useful.
+ * Not all index AMs support scans with no restriction clauses.
+ * We can't generate a scan over an index with amoptionalkey = false
+ * unless there's at least one restriction clause.
*/
- if (restrictclauses != NIL ||
- useful_pathkeys != NIL ||
- index->indpred != NIL)
- add_path(rel, (Path *)
- create_index_path(root, rel, index,
- restrictclauses,
- useful_pathkeys,
- index_is_ordered ?
- ForwardScanDirection :
- NoMovementScanDirection));
+ if (restrictclauses == NIL && !index->amoptionalkey)
+ continue;
/*
- * 5. If the index is ordered, a backwards scan might be
- * interesting. Currently this is only possible for a DESC query
- * result ordering.
+ * 2. Compute pathkeys describing index's ordering, if any, then
+ * see how many of them are actually useful for this query. This
+ * is not relevant unless we are at top level.
*/
- if (index_is_ordered)
+ index_is_ordered = OidIsValid(index->ordering[0]);
+ if (istoplevel && index_is_ordered && !isjoininner)
{
- index_pathkeys = build_index_pathkeys(root, rel, index,
- BackwardScanDirection);
+ index_pathkeys = build_index_pathkeys(root, index,
+ ForwardScanDirection);
useful_pathkeys = truncate_useless_pathkeys(root, rel,
index_pathkeys);
- if (useful_pathkeys != NIL)
- add_path(rel, (Path *)
- create_index_path(root, rel, index,
- restrictclauses,
- useful_pathkeys,
- BackwardScanDirection));
}
+ else
+ useful_pathkeys = NIL;
/*
- * 6. Examine join clauses to see which ones are potentially
- * usable with this index, and generate a list of all other relids
- * that participate in such join clauses. We'll use this list later
- * to recognize outer rels that are equivalent for joining purposes.
- * We compute both per-index and overall-for-relation lists.
+ * 3. Generate an indexscan path if there are relevant restriction
+ * clauses in the current clauses, OR the index ordering is
+ * potentially useful for later merging or final output ordering,
+ * OR the index has a predicate that was proven by the current
+ * clauses.
*/
- join_outerrelids = indexable_outerrelids(rel, index);
- index->outer_relids = join_outerrelids;
- all_join_outerrelids = set_unioni(all_join_outerrelids,
- join_outerrelids);
- }
+ if (found_clause || useful_pathkeys != NIL || useful_predicate)
+ {
+ ipath = create_index_path(root, index,
+ restrictclauses,
+ useful_pathkeys,
+ index_is_ordered ?
+ ForwardScanDirection :
+ NoMovementScanDirection,
+ isjoininner);
+ result = lappend(result, ipath);
+ }
- rel->index_outer_relids = all_join_outerrelids;
-}
+ /*
+ * 4. If the index is ordered, and there is a requested query
+ * ordering that we failed to match, consider variant ways of
+ * achieving the ordering. Again, this is only interesting
+ * at top level.
+ */
+ if (istoplevel && index_is_ordered && !isjoininner &&
+ root->query_pathkeys != NIL &&
+ pathkeys_useful_for_ordering(root, useful_pathkeys) == 0)
+ {
+ ScanDirection scandir;
+ scandir = match_variant_ordering(root, index, restrictclauses);
+ if (!ScanDirectionIsNoMovement(scandir))
+ {
+ ipath = create_index_path(root, index,
+ restrictclauses,
+ root->query_pathkeys,
+ scandir,
+ false);
+ result = lappend(result, ipath);
+ }
+ }
+ }
-/****************************************************************************
- * ---- ROUTINES TO PROCESS 'OR' CLAUSES ----
- ****************************************************************************/
+ return result;
+}
/*
- * match_index_orclauses
- * Attempt to match an index against subclauses within 'or' clauses.
- * Each subclause that does match is marked with the index's node.
+ * generate_bitmap_or_paths
+ * Look through the list of clauses to find OR clauses, and generate
+ * a BitmapOrPath for each one we can handle that way. Return a list
+ * of the generated BitmapOrPaths.
*
- * Essentially, this adds 'index' to the list of subclause indices in
- * the RestrictInfo field of each of the 'or' clauses where it matches.
- * NOTE: we can use storage in the RestrictInfo for this purpose because
- * this processing is only done on single-relation restriction clauses.
- * Therefore, we will never have indexes for more than one relation
- * mentioned in the same RestrictInfo node's list.
- *
- * 'rel' is the node of the relation on which the index is defined.
- * 'index' is the index node.
- * 'restrictinfo_list' is the list of available restriction clauses.
+ * outer_clauses is a list of additional clauses that can be assumed true
+ * for the purpose of generating indexquals, but are not to be searched for
+ * ORs. (See find_usable_indexes() for motivation.)
*/
-static void
-match_index_orclauses(RelOptInfo *rel,
- IndexOptInfo *index,
- List *restrictinfo_list)
+List *
+generate_bitmap_or_paths(PlannerInfo *root, RelOptInfo *rel,
+ List *clauses, List *outer_clauses,
+ bool isjoininner,
+ Relids outer_relids)
{
- List *i;
+ List *result = NIL;
+ List *all_clauses;
+ ListCell *l;
+
+ /*
+ * We can use both the current and outer clauses as context for
+ * find_usable_indexes
+ */
+ all_clauses = list_concat(list_copy(clauses), outer_clauses);
- foreach(i, restrictinfo_list)
+ foreach(l, clauses)
{
- RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(i);
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
+ List *pathlist;
+ Path *bitmapqual;
+ ListCell *j;
+
+ Assert(IsA(rinfo, RestrictInfo));
+ /* Ignore RestrictInfos that aren't ORs */
+ if (!restriction_is_or_clause(rinfo))
+ continue;
- if (restriction_is_or_clause(restrictinfo))
+ /*
+ * We must be able to match at least one index to each of the arms
+ * of the OR, else we can't use it.
+ */
+ pathlist = NIL;
+ foreach(j, ((BoolExpr *) rinfo->orclause)->args)
{
+ Node *orarg = (Node *) lfirst(j);
+ List *indlist;
+
+ /* OR arguments should be ANDs or sub-RestrictInfos */
+ if (and_clause(orarg))
+ {
+ List *andargs = ((BoolExpr *) orarg)->args;
+
+ indlist = find_usable_indexes(root, rel,
+ andargs,
+ all_clauses,
+ false,
+ isjoininner,
+ outer_relids);
+ /* Recurse in case there are sub-ORs */
+ indlist = list_concat(indlist,
+ generate_bitmap_or_paths(root, rel,
+ andargs,
+ all_clauses,
+ isjoininner,
+ outer_relids));
+ }
+ else
+ {
+ Assert(IsA(orarg, RestrictInfo));
+ Assert(!restriction_is_or_clause((RestrictInfo *) orarg));
+ indlist = find_usable_indexes(root, rel,
+ list_make1(orarg),
+ all_clauses,
+ false,
+ isjoininner,
+ outer_relids);
+ }
+ /*
+ * If nothing matched this arm, we can't do anything
+ * with this OR clause.
+ */
+ if (indlist == NIL)
+ {
+ pathlist = NIL;
+ break;
+ }
/*
- * Add this index to the subclause index list for each
- * subclause that it matches.
+ * OK, pick the most promising AND combination,
+ * and add it to pathlist.
*/
- restrictinfo->subclauseindices =
- match_index_orclause(rel, index,
- ((BoolExpr *) restrictinfo->clause)->args,
- restrictinfo->subclauseindices);
+ bitmapqual = choose_bitmap_and(root, rel, indlist);
+ pathlist = lappend(pathlist, bitmapqual);
+ }
+ /*
+ * If we have a match for every arm, then turn them
+ * into a BitmapOrPath, and add to result list.
+ */
+ if (pathlist != NIL)
+ {
+ bitmapqual = (Path *) create_bitmap_or_path(root, rel, pathlist);
+ result = lappend(result, bitmapqual);
}
}
+
+ 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 the
- * index's specified operator class, and
- * (2) one operand of the subclause matches the index key.
+ * choose_bitmap_and
+ * Given a nonempty list of bitmap paths, AND them into one path.
*
- * If a subclause is an 'and' clause, then it matches if any of its
- * subclauses is an opclause that matches.
+ * This is a nontrivial decision since we can legally use any subset of the
+ * given path set. We want to choose a good tradeoff between selectivity
+ * and cost of computing the bitmap.
*
- * '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), 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
- * 'or-clauses', d,e,f match the second subclause, no indices
- * match the third, g,h match the fourth, etc.
+ * The result is either a single one of the inputs, or a BitmapAndPath
+ * combining multiple inputs.
*/
-static List *
-match_index_orclause(RelOptInfo *rel,
- IndexOptInfo *index,
- List *or_clauses,
- List *other_matching_indices)
+static Path *
+choose_bitmap_and(PlannerInfo *root, RelOptInfo *rel, List *paths)
{
- List *matching_indices;
- List *index_list;
- List *clist;
+ int npaths = list_length(paths);
+ Path **patharray;
+ Cost costsofar;
+ List *qualsofar;
+ ListCell *lastcell;
+ int i;
+ ListCell *l;
+
+ Assert(npaths > 0); /* else caller error */
+ if (npaths == 1)
+ return (Path *) linitial(paths); /* easy case */
/*
- * first time through, we create list of same length as OR clause,
- * containing an empty sublist for each subclause.
+ * In theory we should consider every nonempty subset of the given paths.
+ * In practice that seems like overkill, given the crude nature of the
+ * estimates, not to mention the possible effects of higher-level AND and
+ * OR clauses. As a compromise, we sort the paths by selectivity.
+ * We always take the first, and sequentially add on paths that result
+ * in a lower estimated cost.
+ *
+ * We also make some effort to detect directly redundant input paths,
+ * as can happen if there are multiple possibly usable indexes. For
+ * this we look only at plain IndexPath inputs, not at sub-OR clauses.
+ * And we consider an index redundant if all its index conditions were
+ * already used by earlier indexes. (We could use predicate_implied_by
+ * to have a more intelligent, but much more expensive, check --- but in
+ * most cases simple pointer equality should suffice, since after all the
+ * index conditions are all coming from the same RestrictInfo lists.)
+ *
+ * XXX is there any risk of throwing away a useful partial index here
+ * because we don't explicitly look at indpred? At least in simple
+ * cases, the partial index will sort before competing non-partial
+ * indexes and so it makes the right choice, but perhaps we need to
+ * work harder.
+ *
+ * Note: outputting the selected sub-paths in selectivity order is a good
+ * thing even if we weren't using that as part of the selection method,
+ * because it makes the short-circuit case in MultiExecBitmapAnd() more
+ * likely to apply.
*/
- if (!other_matching_indices)
+
+ /* Convert list to array so we can apply qsort */
+ patharray = (Path **) palloc(npaths * sizeof(Path *));
+ i = 0;
+ foreach(l, paths)
{
- matching_indices = NIL;
- foreach(clist, or_clauses)
- matching_indices = lcons(NIL, matching_indices);
+ patharray[i++] = (Path *) lfirst(l);
}
- else
- matching_indices = other_matching_indices;
+ qsort(patharray, npaths, sizeof(Path *), bitmap_path_comparator);
- index_list = matching_indices;
+ paths = list_make1(patharray[0]);
+ costsofar = bitmap_and_cost_est(root, rel, paths);
+ if (IsA(patharray[0], IndexPath))
+ qualsofar = list_copy(((IndexPath *) patharray[0])->indexclauses);
+ else
+ qualsofar = NIL;
+ lastcell = list_head(paths); /* for quick deletions */
- foreach(clist, or_clauses)
+ for (i = 1; i < npaths; i++)
{
- Expr *clause = lfirst(clist);
+ Path *newpath = patharray[i];
+ List *newqual = NIL;
+ Cost newcost;
- if (match_or_subclause_to_indexkey(rel, index, clause))
+ if (IsA(newpath, IndexPath))
{
- /* OK to add this index to sublist for this subclause */
- lfirst(matching_indices) = lcons(index,
- lfirst(matching_indices));
+ newqual = ((IndexPath *) newpath)->indexclauses;
+ if (list_difference_ptr(newqual, qualsofar) == NIL)
+ continue; /* redundant */
}
- matching_indices = lnext(matching_indices);
+ paths = lappend(paths, newpath);
+ newcost = bitmap_and_cost_est(root, rel, paths);
+ if (newcost < costsofar)
+ {
+ costsofar = newcost;
+ if (newqual)
+ qualsofar = list_concat(qualsofar, list_copy(newqual));
+ lastcell = lnext(lastcell);
+ }
+ else
+ {
+ paths = list_delete_cell(paths, lnext(lastcell), lastcell);
+ }
+ Assert(lnext(lastcell) == NULL);
}
- return index_list;
+ if (list_length(paths) == 1)
+ return (Path *) linitial(paths); /* no need for AND */
+ return (Path *) create_bitmap_and_path(root, rel, paths);
}
-/*
- * See if a subclause of an OR clause matches an index.
- *
- * We accept the subclause if it is an operator clause that matches the
- * index, or if it is an AND clause any of whose members is an opclause
- * that matches the index.
- *
- * For multi-key indexes, we only look for matches to the first key;
- * without such a match the index is useless. If the clause is an AND
- * then we may be able to extract additional subclauses to use with the
- * later indexkeys, but we need not worry about that until
- * extract_or_indexqual_conditions() is called (if it ever is).
- */
-static bool
-match_or_subclause_to_indexkey(RelOptInfo *rel,
- IndexOptInfo *index,
- Expr *clause)
+/* qsort comparator to sort in increasing selectivity order */
+static int
+bitmap_path_comparator(const void *a, const void *b)
{
- int indexkey = index->indexkeys[0];
- Oid opclass = index->classlist[0];
-
- if (and_clause((Node *) clause))
- {
- List *item;
-
- foreach(item, ((BoolExpr *) clause)->args)
- {
- if (match_clause_to_indexkey(rel, index, indexkey, opclass,
- lfirst(item)))
- return true;
- }
- return false;
- }
- else
- return match_clause_to_indexkey(rel, index, indexkey, opclass,
- clause);
+ Path *pa = *(Path * const *) a;
+ Path *pb = *(Path * const *) b;
+ Cost acost;
+ Cost bcost;
+ Selectivity aselec;
+ Selectivity bselec;
+
+ cost_bitmap_tree_node(pa, &acost, &aselec);
+ cost_bitmap_tree_node(pb, &bcost, &bselec);
+
+ if (aselec < bselec)
+ return -1;
+ if (aselec > bselec)
+ return 1;
+ /* if identical selectivity, sort by cost */
+ if (acost < bcost)
+ return -1;
+ if (acost > bcost)
+ return 1;
+ return 0;
}
-/*----------
- * Given an OR subclause that has previously been determined to match
- * the specified index, extract a list of specific opclauses that can be
- * used as indexquals.
- *
- * In the simplest case this just means making a one-element list of the
- * given opclause. However, if the OR subclause is an AND, we have to
- * scan it to find the opclause(s) that match the index. (There should
- * be at least one, if match_or_subclause_to_indexkey succeeded, but there
- * could be more.)
- *
- * Also, we can look at other restriction clauses of the rel to discover
- * additional candidate indexquals: for example, consider
- * ... where (a = 11 or a = 12) and b = 42;
- * If we are dealing with an index on (a,b) then we can include the clause
- * b = 42 in the indexqual list generated for each of the OR subclauses.
- * Essentially, we are making an index-specific transformation from CNF to
- * DNF. (NOTE: when we do this, we end up with a slightly inefficient plan
- * because create_indexscan_plan is not very bright about figuring out which
- * restriction clauses are implied by the generated indexqual condition.
- * Currently we'll end up rechecking both the OR clause and the transferred
- * restriction clause as qpquals. FIXME someday.)
- *
- * Also, we apply expand_indexqual_conditions() to convert any special
- * matching opclauses to indexable operators.
- *
- * The passed-in clause is not changed.
- *----------
+/*
+ * Estimate the cost of actually executing a BitmapAnd with the given
+ * inputs.
*/
-List *
-extract_or_indexqual_conditions(RelOptInfo *rel,
- IndexOptInfo *index,
- Expr *orsubclause)
+static Cost
+bitmap_and_cost_est(PlannerInfo *root, RelOptInfo *rel, List *paths)
{
- List *quals = NIL;
- int *indexkeys = index->indexkeys;
- Oid *classes = index->classlist;
-
- /*
- * Extract relevant indexclauses in indexkey order. This is
- * essentially just like group_clauses_by_indexkey() except that the
- * input and output are lists of bare clauses, not of RestrictInfo
- * nodes.
- */
- do
- {
- int curIndxKey = indexkeys[0];
- Oid curClass = classes[0];
- List *clausegroup = NIL;
- List *item;
-
- if (and_clause((Node *) orsubclause))
- {
- foreach(item, ((BoolExpr *) orsubclause)->args)
- {
- Expr *subsubclause = (Expr *) lfirst(item);
-
- if (match_clause_to_indexkey(rel, index,
- curIndxKey, curClass,
- subsubclause))
- clausegroup = lappend(clausegroup, subsubclause);
- }
- }
- else if (match_clause_to_indexkey(rel, index,
- curIndxKey, curClass,
- orsubclause))
- clausegroup = makeList1(orsubclause);
-
- /*
- * If we found no clauses for this indexkey in the OR subclause
- * itself, try looking in the rel's top-level restriction list.
- */
- if (clausegroup == NIL)
- {
- foreach(item, rel->baserestrictinfo)
- {
- RestrictInfo *rinfo = (RestrictInfo *) lfirst(item);
+ BitmapAndPath apath;
+ Path bpath;
- if (match_clause_to_indexkey(rel, index,
- curIndxKey, curClass,
- rinfo->clause))
- clausegroup = lappend(clausegroup, rinfo->clause);
- }
- }
-
- /*
- * If still no clauses match this key, we're done; we don't want
- * to look at keys to its right.
- */
- if (clausegroup == NIL)
- break;
-
- quals = nconc(quals, clausegroup);
-
- indexkeys++;
- classes++;
-
- } while (!DoneMatchingIndexKeys(indexkeys, classes));
+ /* Set up a dummy BitmapAndPath */
+ apath.path.type = T_BitmapAndPath;
+ apath.path.parent = rel;
+ apath.bitmapquals = paths;
+ cost_bitmap_and_node(&apath, root);
- if (quals == NIL)
- elog(ERROR, "extract_or_indexqual_conditions: no matching clause");
+ /* Now we can do cost_bitmap_heap_scan */
+ cost_bitmap_heap_scan(&bpath, root, rel, (Path *) &apath, false);
- return expand_indexqual_conditions(quals);
+ return bpath.total_cost;
}
/*
* group_clauses_by_indexkey
- * Generates a list of restriction clauses that can be used with an index.
+ * Find restriction clauses that can be used with an index.
+ *
+ * Returns a list of sublists of RestrictInfo nodes for clauses that can be
+ * used with this index. Each sublist contains clauses that can be used
+ * with one index key (in no particular order); the top list is ordered by
+ * index key. (This is depended on by expand_indexqual_conditions().)
+ *
+ * We can use clauses from either the current clauses or outer_clauses lists,
+ * but *found_clause is set TRUE only if we used at least one clause from
+ * the "current clauses" list. See find_usable_indexes() for motivation.
*
- * 'rel' is the node of the relation itself.
- * 'index' is a index on 'rel'.
+ * outer_relids determines what Vars will be allowed on the other side
+ * of a possible index qual; see match_clause_to_indexcol().
*
- * Returns a list of all the RestrictInfo nodes for clauses that can be
- * used with this index.
+ * If the index has amoptionalkey = false, we give up and return NIL when
+ * there are no restriction clauses matching the first index key. Otherwise,
+ * we return NIL if there are no restriction clauses matching any index key.
+ * A non-NIL result will have one (possibly empty) sublist for each index key.
*
- * The list is ordered by index key. (This is not depended on by any part
- * of the planner, so far as I can tell; but some parts of the executor
- * do assume that the indxqual list ultimately delivered to the executor
- * is so ordered. One such place is _bt_orderkeys() in the btree support.
- * Perhaps that ought to be fixed someday --- tgl 7/00)
+ * Example: given an index on (A,B,C), we would return ((C1 C2) () (C3 C4))
+ * if we find that clauses C1 and C2 use column A, clauses C3 and C4 use
+ * column C, and no clauses use column B.
*
- * 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.
+ * Note: in some circumstances we may find the same RestrictInfos coming
+ * from multiple places. Defend against redundant outputs by using
+ * list_append_unique_ptr (pointer equality should be good enough).
*/
-static List *
-group_clauses_by_indexkey(RelOptInfo *rel, IndexOptInfo *index)
+List *
+group_clauses_by_indexkey(IndexOptInfo *index,
+ List *clauses, List *outer_clauses,
+ Relids outer_relids,
+ bool *found_clause)
{
List *clausegroup_list = NIL;
- List *restrictinfo_list = rel->baserestrictinfo;
- int *indexkeys = index->indexkeys;
+ bool found_outer_clause = false;
+ int indexcol = 0;
Oid *classes = index->classlist;
- if (restrictinfo_list == NIL)
- return NIL;
-
- do
- {
- int curIndxKey = indexkeys[0];
- Oid curClass = classes[0];
- List *clausegroup = NIL;
- List *i;
-
- foreach(i, restrictinfo_list)
- {
- RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
-
- if (match_clause_to_indexkey(rel,
- index,
- curIndxKey,
- curClass,
- rinfo->clause))
- clausegroup = lappend(clausegroup, rinfo);
- }
-
- /*
- * 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_list = nconc(clausegroup_list, clausegroup);
-
- indexkeys++;
- classes++;
-
- } while (!DoneMatchingIndexKeys(indexkeys, classes));
-
- /* clausegroup_list holds all matched clauses ordered by indexkeys */
- return clausegroup_list;
-}
+ *found_clause = false; /* default result */
-/*
- * group_clauses_by_indexkey_for_join
- * Generates a list of clauses that can be used with an index
- * to scan the inner side of a nestloop join.
- *
- * This is much like group_clauses_by_indexkey(), but we consider both
- * join and restriction clauses. Any joinclause that uses only otherrels
- * in the specified outer_relids is fair game. But there must be at least
- * one such joinclause in the final list, otherwise we return NIL indicating
- * that this index isn't interesting as an inner indexscan. (A scan using
- * only restriction clauses shouldn't be created here, because a regular Path
- * will already have been generated for it.)
- */
-static List *
-group_clauses_by_indexkey_for_join(RelOptInfo *rel, IndexOptInfo *index,
- Relids outer_relids, bool isouterjoin)
-{
- List *clausegroup_list = NIL;
- bool jfound = false;
- int *indexkeys = index->indexkeys;
- Oid *classes = index->classlist;
+ if (clauses == NIL && outer_clauses == NIL)
+ return NIL; /* cannot succeed */
do
{
- int curIndxKey = indexkeys[0];
Oid curClass = classes[0];
List *clausegroup = NIL;
- List *i;
+ ListCell *l;
- /* Look for joinclauses that are usable with given outer_relids */
- foreach(i, rel->joininfo)
+ /* check the current clauses */
+ foreach(l, clauses)
{
- JoinInfo *joininfo = (JoinInfo *) lfirst(i);
- List *j;
-
- if (!is_subseti(joininfo->unjoined_relids, outer_relids))
- continue;
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
- foreach(j, joininfo->jinfo_restrictinfo)
+ Assert(IsA(rinfo, RestrictInfo));
+ if (match_clause_to_indexcol(index,
+ indexcol,
+ curClass,
+ rinfo,
+ outer_relids))
{
- RestrictInfo *rinfo = (RestrictInfo *) lfirst(j);
-
- /* Can't use pushed-down clauses in outer join */
- if (isouterjoin && rinfo->ispusheddown)
- continue;
-
- if (match_join_clause_to_indexkey(rel,
- index,
- curIndxKey,
- curClass,
- rinfo->clause))
- {
- clausegroup = lappend(clausegroup, rinfo);
- jfound = true;
- }
+ clausegroup = list_append_unique_ptr(clausegroup, rinfo);
+ *found_clause = true;
}
}
- /* We can also use plain restriction clauses for the rel */
- foreach(i, rel->baserestrictinfo)
+ /* check the outer clauses */
+ foreach(l, outer_clauses)
{
- RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
-
- /* Can't use pushed-down clauses in outer join */
- if (isouterjoin && rinfo->ispusheddown)
- continue;
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
- if (match_clause_to_indexkey(rel,
- index,
- curIndxKey,
+ Assert(IsA(rinfo, RestrictInfo));
+ if (match_clause_to_indexcol(index,
+ indexcol,
curClass,
- rinfo->clause))
- clausegroup = lappend(clausegroup, rinfo);
+ rinfo,
+ outer_relids))
+ {
+ clausegroup = list_append_unique_ptr(clausegroup, rinfo);
+ found_outer_clause = true;
+ }
}
/*
- * If no clauses match this key, we're done; we don't want to look
- * at keys to its right.
+ * If no clauses match this key, check for amoptionalkey restriction.
*/
- if (clausegroup == NIL)
- break;
+ if (clausegroup == NIL && !index->amoptionalkey && indexcol == 0)
+ return NIL;
- clausegroup_list = nconc(clausegroup_list, clausegroup);
+ clausegroup_list = lappend(clausegroup_list, clausegroup);
- indexkeys++;
+ indexcol++;
classes++;
- } while (!DoneMatchingIndexKeys(indexkeys, classes));
+ } while (!DoneMatchingIndexKeys(classes));
- /*
- * if no join clause was matched then forget it, per comments above.
- */
- if (!jfound)
- {
- freeList(clausegroup_list);
- return NIL;
- }
+ if (!*found_clause && !found_outer_clause)
+ return NIL; /* no indexable clauses anywhere */
- /* clausegroup_list holds all matched clauses ordered by indexkeys */
return clausegroup_list;
}
/*
- * match_clause_to_indexkey()
- * Determines whether a restriction clause matches a key of an index.
+ * match_clause_to_indexcol()
+ * Determines whether a restriction clause matches a column of an index.
*
- * To match, the clause:
+ * To match a normal index, the clause:
*
* (1) must be in the form (indexkey op const) or (const op indexkey);
* and
* (2) must contain an operator which is in the same class as the index
- * operator for this key, or is a "special" operator as recognized
+ * operator for this column, or is a "special" operator as recognized
* by match_special_index_operator().
*
+ * Our definition of "const" is pretty liberal: we allow Vars belonging
+ * to the caller-specified outer_relids relations (which had better not
+ * include the relation whose index is being tested). outer_relids should
+ * be NULL when checking simple restriction clauses, and the outer side
+ * of the join when building a join inner scan. Other than that, the
+ * only thing we don't like is volatile functions.
+ *
+ * Note: in most cases we already know that the clause as a whole uses
+ * vars from the interesting set of relations. The reason for the
+ * outer_relids test is to reject clauses like (a.f1 OP (b.f2 OP a.f3));
+ * that's not processable by an indexscan nestloop join on A, whereas
+ * (a.f1 OP (b.f2 OP c.f3)) is.
+ *
* Presently, the executor can only deal with indexquals that have the
* indexkey on the left, so we can only use clauses that have the indexkey
* on the right if we can commute the clause to put the key on the left.
* We do not actually do the commuting here, but we check whether a
* suitable commutator operator is available.
*
- * 'rel' is the relation of interest.
- * 'index' is an index on 'rel'.
- * 'indexkey' is a key of 'index'.
+ * For boolean indexes, it is also possible to match the clause directly
+ * to the indexkey; or perhaps the clause is (NOT indexkey).
+ *
+ * 'index' is the index of interest.
+ * 'indexcol' is a column number of 'index' (counting from 0).
* 'opclass' is the corresponding operator class.
- * 'clause' is the clause to be tested.
+ * 'rinfo' is the clause to be tested (as a RestrictInfo node).
*
* Returns true if the clause can be used with this index key.
*
* responsibility of higher-level routines to cope with those.
*/
static bool
-match_clause_to_indexkey(RelOptInfo *rel,
- IndexOptInfo *index,
- int indexkey,
+match_clause_to_indexcol(IndexOptInfo *index,
+ int indexcol,
Oid opclass,
- Expr *clause)
+ RestrictInfo *rinfo,
+ Relids outer_relids)
{
+ Expr *clause = rinfo->clause;
Node *leftop,
*rightop;
- /* Clause must be a binary opclause. */
+ /* First check for boolean-index cases. */
+ if (IsBooleanOpclass(opclass))
+ {
+ if (match_boolean_index_clause((Node *) clause, indexcol, index))
+ return true;
+ }
+
+ /* Else clause must be a binary opclause. */
if (!is_opclause(clause))
return false;
leftop = get_leftop(clause);
return false;
/*
- * Check for clauses of the form:
- * (indexkey operator constant) or (constant operator indexkey).
- * Anything that is a "pseudo constant" expression will do.
+ * Check for clauses of the form: (indexkey operator constant) or
+ * (constant operator indexkey). See above notes about const-ness.
*/
- if (match_index_to_operand(indexkey, leftop, rel, index) &&
- is_pseudo_constant_clause(rightop))
+ if (match_index_to_operand(leftop, indexcol, index) &&
+ bms_is_subset(rinfo->right_relids, outer_relids) &&
+ !contain_volatile_functions(rightop))
{
if (is_indexable_operator(clause, opclass, true))
return true;
/*
- * If we didn't find a member of the index's opclass, see
- * whether it is a "special" indexable operator.
+ * If we didn't find a member of the index's opclass, see whether
+ * it is a "special" indexable operator.
*/
if (match_special_index_operator(clause, opclass, true))
return true;
return false;
}
- if (match_index_to_operand(indexkey, rightop, rel, index) &&
- is_pseudo_constant_clause(leftop))
+ if (match_index_to_operand(rightop, indexcol, index) &&
+ bms_is_subset(rinfo->left_relids, outer_relids) &&
+ !contain_volatile_functions(leftop))
{
if (is_indexable_operator(clause, opclass, false))
return true;
/*
- * If we didn't find a member of the index's opclass, see
- * whether it is a "special" indexable operator.
+ * If we didn't find a member of the index's opclass, see whether
+ * it is a "special" indexable operator.
*/
if (match_special_index_operator(clause, opclass, false))
return true;
}
/*
- * match_join_clause_to_indexkey()
- * Determines whether a join clause matches a key of an index.
- *
- * To match, the clause:
- *
- * (1) must be in the form (indexkey op others) or (others op indexkey),
- * where others is an expression involving only vars of the other
- * relation(s); and
- * (2) must contain an operator which is in the same class as the index
- * operator for this key, or is a "special" operator as recognized
- * by match_special_index_operator().
- *
- * As above, we must be able to commute the clause to put the indexkey
- * on the left.
- *
- * Note that we already know that the clause as a whole uses vars from
- * the interesting set of relations. But we need to defend against
- * expressions like (a.f1 OP (b.f2 OP a.f3)); that's not processable by
- * an indexscan nestloop join, whereas (a.f1 OP (b.f2 OP c.f3)) is.
- *
- * 'rel' is the relation of interest.
- * 'index' is an index on 'rel'.
- * 'indexkey' is a key of 'index'.
- * 'opclass' is the corresponding operator class.
- * 'clause' is the clause to be tested.
+ * indexable_operator
+ * Does a binary opclause contain an operator matching the index opclass?
*
- * Returns true if the clause can be used with this index key.
+ * If the indexkey is on the right, what we actually want to know
+ * is whether the operator has a commutator operator that matches
+ * the index's opclass.
*
- * NOTE: returns false if clause is an OR or AND clause; it is the
- * responsibility of higher-level routines to cope with those.
+ * Returns the OID of the matching operator, or InvalidOid if no match.
+ * (Formerly, this routine might return a binary-compatible operator
+ * rather than the original one, but that kluge is history.)
*/
-static bool
-match_join_clause_to_indexkey(RelOptInfo *rel,
- IndexOptInfo *index,
- int indexkey,
- Oid opclass,
- Expr *clause)
-{
- Node *leftop,
- *rightop;
-
- /* Clause must be a binary opclause. */
- if (!is_opclause(clause))
- return false;
- leftop = get_leftop(clause);
- rightop = get_rightop(clause);
- if (!leftop || !rightop)
- return false;
-
- /*
- * Check for an indexqual that could be handled by a nestloop
- * join. We need the index key to be compared against an
- * expression that uses none of the indexed relation's vars and
- * contains no volatile functions.
- */
- if (match_index_to_operand(indexkey, leftop, rel, index))
- {
- List *othervarnos = pull_varnos(rightop);
- bool isIndexable;
-
- isIndexable =
- !intMember(lfirsti(rel->relids), othervarnos) &&
- !contain_volatile_functions(rightop) &&
- is_indexable_operator(clause, opclass, true);
- freeList(othervarnos);
- return isIndexable;
- }
-
- if (match_index_to_operand(indexkey, rightop, rel, index))
- {
- List *othervarnos = pull_varnos(leftop);
- bool isIndexable;
-
- isIndexable =
- !intMember(lfirsti(rel->relids), othervarnos) &&
- !contain_volatile_functions(leftop) &&
- is_indexable_operator(clause, opclass, false);
- freeList(othervarnos);
- return isIndexable;
- }
-
- return false;
-}
-
-/*
- * indexable_operator
- * Does a binary opclause contain an operator matching the index opclass?
- *
- * If the indexkey is on the right, what we actually want to know
- * is whether the operator has a commutator operator that matches
- * the index's opclass.
- *
- * Returns the OID of the matching operator, or InvalidOid if no match.
- * (Formerly, this routine might return a binary-compatible operator
- * rather than the original one, but that kluge is history.)
- */
-static Oid
-indexable_operator(Expr *clause, Oid opclass, bool indexkey_on_left)
+static Oid
+indexable_operator(Expr *clause, Oid opclass, bool indexkey_on_left)
{
Oid expr_op = ((OpExpr *) clause)->opno;
Oid commuted_op;
****************************************************************************/
/*
- * pred_test
- * Does the "predicate inclusion test" for partial indexes.
- *
- * Recursively checks whether the clauses in restrictinfo_list imply
- * that the given predicate is true.
- *
- * This routine (together with the routines it calls) iterates over
- * ANDs in the predicate first, then reduces the qualification
- * clauses down to their constituent terms, and iterates over ORs
- * in the predicate last. This order is important to make the test
- * succeed whenever possible (assuming the predicate has been converted
- * to CNF format). --Nels, Jan '93
+ * check_partial_indexes
+ * Check each partial index of the relation, and mark it predOK or not
+ * depending on whether the predicate is satisfied for this query.
*/
-static bool
-pred_test(List *predicate_list, List *restrictinfo_list, List *joininfo_list,
- int relvarno)
+void
+check_partial_indexes(PlannerInfo *root, RelOptInfo *rel)
{
- List *pred;
+ List *restrictinfo_list = rel->baserestrictinfo;
+ ListCell *ilist;
/*
* Note: if Postgres tried to optimize queries by forming equivalence
* classes over equi-joined attributes (i.e., if it recognized that a
* qualification such as "where a.b=c.d and a.b=5" could make use of
* an index on c.d), then we could use that equivalence class info
- * here with joininfo_list to do more complete tests for the usability
+ * here with joininfo lists to do more complete tests for the usability
* of a partial index. For now, the test only uses restriction
- * clauses (those in restrictinfo_list). --Nels, Dec '92
+ * clauses (those in baserestrictinfo). --Nels, Dec '92
*
* XXX as of 7.1, equivalence class info *is* available. Consider
* improving this code as foreseen by Nels.
*/
- if (predicate_list == NIL)
- return true; /* no predicate: the index is usable */
- if (restrictinfo_list == NIL)
- return false; /* no restriction clauses: the test must
- * fail */
-
- /*
- * The predicate as stored in the index definition will use varno 1
- * for its Vars referencing the indexed relation. If the indexed
- * relation isn't varno 1 in the query, we must adjust the predicate
- * to make the Vars match, else equal() won't work.
- */
- if (relvarno != 1)
+ foreach(ilist, rel->indexlist)
{
- predicate_list = copyObject(predicate_list);
- ChangeVarNodes((Node *) predicate_list, 1, relvarno, 0);
- }
+ IndexOptInfo *index = (IndexOptInfo *) lfirst(ilist);
- foreach(pred, predicate_list)
- {
- /*
- * if any clause is not implied, the whole predicate is not
- * implied. Note we assume that any sub-ANDs have been flattened
- * when the predicate was fed through canonicalize_qual().
- */
- if (!pred_test_restrict_list(lfirst(pred), restrictinfo_list))
- return false;
+ if (index->indpred == NIL)
+ continue; /* ignore non-partial indexes */
+
+ index->predOK = predicate_implied_by(index->indpred,
+ restrictinfo_list);
}
- return true;
}
+/****************************************************************************
+ * ---- ROUTINES TO CHECK JOIN CLAUSES ----
+ ****************************************************************************/
/*
- * pred_test_restrict_list
- * Does the "predicate inclusion test" for one conjunct of a predicate
- * expression.
+ * indexable_outerrelids
+ * Finds all other relids that participate in any indexable join clause
+ * for the specified table. Returns a set of relids.
*/
-static bool
-pred_test_restrict_list(Expr *predicate, List *restrictinfo_list)
+static Relids
+indexable_outerrelids(RelOptInfo *rel)
{
- List *item;
+ Relids outer_relids = NULL;
+ ListCell *l;
- foreach(item, restrictinfo_list)
+ /*
+ * Examine each joinclause in the joininfo list to see if it matches any
+ * key of any index. If so, add the clause's other rels to the result.
+ */
+ foreach(l, rel->joininfo)
{
- RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(item);
+ RestrictInfo *joininfo = (RestrictInfo *) lfirst(l);
+ Relids other_rels;
- /* if any clause implies the predicate, return true */
- if (pred_test_recurse_clause(predicate,
- (Node *) restrictinfo->clause))
- return true;
+ other_rels = bms_difference(joininfo->required_relids, rel->relids);
+ if (matches_any_index(joininfo, rel, other_rels))
+ outer_relids = bms_join(outer_relids, other_rels);
+ else
+ bms_free(other_rels);
}
- return false;
-}
+ return outer_relids;
+}
/*
- * pred_test_recurse_clause
- * Does the "predicate inclusion test" for a general restriction-clause
- * expression. Here we recursively deal with the possibility that the
- * restriction clause is itself an AND or OR structure.
+ * matches_any_index
+ * Workhorse for indexable_outerrelids: see if a joinclause can be
+ * matched to any index of the given rel.
*/
static bool
-pred_test_recurse_clause(Expr *predicate, Node *clause)
+matches_any_index(RestrictInfo *rinfo, RelOptInfo *rel, Relids outer_relids)
{
- List *items,
- *item;
+ ListCell *l;
- Assert(clause != NULL);
- if (or_clause(clause))
- {
- items = ((BoolExpr *) clause)->args;
- foreach(item, items)
- {
- /* if any OR item doesn't imply the predicate, clause doesn't */
- if (!pred_test_recurse_clause(predicate, lfirst(item)))
- return false;
- }
- return true;
- }
- else if (and_clause(clause))
+ Assert(IsA(rinfo, RestrictInfo));
+
+ if (restriction_is_or_clause(rinfo))
{
- items = ((BoolExpr *) clause)->args;
- foreach(item, items)
+ foreach(l, ((BoolExpr *) rinfo->orclause)->args)
{
- /*
- * if any AND item implies the predicate, the whole clause
- * does
- */
- if (pred_test_recurse_clause(predicate, lfirst(item)))
- return true;
- }
- return false;
- }
- else
- return pred_test_recurse_pred(predicate, clause);
-}
+ Node *orarg = (Node *) lfirst(l);
+ /* OR arguments should be ANDs or sub-RestrictInfos */
+ if (and_clause(orarg))
+ {
+ ListCell *j;
-/*
- * pred_test_recurse_pred
- * Does the "predicate inclusion test" for one conjunct of a predicate
- * expression for a simple restriction clause. Here we recursively deal
- * with the possibility that the predicate conjunct is itself an AND or
- * OR structure.
- */
-static bool
-pred_test_recurse_pred(Expr *predicate, Node *clause)
-{
- List *items,
- *item;
+ /* Recurse to examine AND items and sub-ORs */
+ foreach(j, ((BoolExpr *) orarg)->args)
+ {
+ RestrictInfo *arinfo = (RestrictInfo *) lfirst(j);
- Assert(predicate != NULL);
- if (or_clause((Node *) predicate))
- {
- items = ((BoolExpr *) predicate)->args;
- foreach(item, items)
- {
- /* if any item is implied, the whole predicate is implied */
- if (pred_test_recurse_pred(lfirst(item), clause))
- return true;
+ if (matches_any_index(arinfo, rel, outer_relids))
+ return true;
+ }
+ }
+ else
+ {
+ /* Recurse to examine simple clause */
+ Assert(IsA(orarg, RestrictInfo));
+ Assert(!restriction_is_or_clause((RestrictInfo *) orarg));
+ if (matches_any_index((RestrictInfo *) orarg, rel,
+ outer_relids))
+ return true;
+ }
}
+
return false;
}
- else if (and_clause((Node *) predicate))
+
+ /* Normal case for a simple restriction clause */
+ foreach(l, rel->indexlist)
{
- items = ((BoolExpr *) predicate)->args;
- foreach(item, items)
- {
- /*
- * if any item is not implied, the whole predicate is not
- * implied
- */
- if (!pred_test_recurse_pred(lfirst(item), clause))
- return false;
- }
- return true;
- }
- else
- return pred_test_simple_clause(predicate, clause);
-}
+ IndexOptInfo *index = (IndexOptInfo *) lfirst(l);
+ int indexcol = 0;
+ Oid *classes = index->classlist;
+ do
+ {
+ Oid curClass = classes[0];
-/*
- * Define an "operator implication table" for btree operators ("strategies").
- * The "strategy numbers" are: (1) < (2) <= (3) = (4) >= (5) >
- *
- * The interpretation of:
- *
- * test_op = BT_implic_table[given_op-1][target_op-1]
- *
- * where test_op, given_op and target_op are strategy numbers (from 1 to 5)
- * of btree operators, is as follows:
- *
- * If you know, for some ATTR, that "ATTR given_op CONST1" is true, and you
- * want to determine whether "ATTR target_op CONST2" must also be true, then
- * you can use "CONST1 test_op CONST2" as a test. If this test returns true,
- * then the target expression must be true; if the test returns false, then
- * the target expression may be false.
- *
- * An entry where test_op==0 means the implication cannot be determined, i.e.,
- * this test should always be considered false.
- */
+ if (match_clause_to_indexcol(index,
+ indexcol,
+ curClass,
+ rinfo,
+ outer_relids))
+ return true;
-static const StrategyNumber
- BT_implic_table[BTMaxStrategyNumber][BTMaxStrategyNumber] = {
- {2, 2, 0, 0, 0},
- {1, 2, 0, 0, 0},
- {1, 2, 3, 4, 5},
- {0, 0, 0, 4, 5},
- {0, 0, 0, 4, 4}
-};
+ indexcol++;
+ classes++;
+ } while (!DoneMatchingIndexKeys(classes));
+ }
+ return false;
+}
/*
- * pred_test_simple_clause
- * Does the "predicate inclusion test" for a "simple clause" predicate
- * and a "simple clause" restriction.
- *
- * We have two strategies for determining whether one simple clause
- * implies another. A simple and general way is to see if they are
- * equal(); this works for any kind of expression. (Actually, there
- * is an implied assumption that the functions in the expression are
- * immutable, ie dependent only on their input arguments --- but this
- * was checked for the predicate by CheckPredicate().)
- *
- * Our other way works only for (binary boolean) operators that are
- * in some btree operator class. We use the above operator implication
- * table to be able to derive implications between nonidentical clauses.
+ * best_inner_indexscan
+ * Finds the best available inner indexscan for a nestloop join
+ * with the given rel on the inside and the given outer_relids outside.
+ * May return NULL if there are no possible inner indexscans.
*
- * Eventually, rtree operators could also be handled by defining an
- * appropriate "RT_implic_table" array.
+ * We ignore ordering considerations (since a nestloop's inner scan's order
+ * is uninteresting). Also, we consider only total cost when deciding which
+ * of two possible paths is better --- this assumes that all indexpaths have
+ * negligible startup cost. (True today, but someday we might have to think
+ * harder.) Therefore, there is only one dimension of comparison and so it's
+ * sufficient to return a single "best" path.
*/
-static bool
-pred_test_simple_clause(Expr *predicate, Node *clause)
+Path *
+best_inner_indexscan(PlannerInfo *root, RelOptInfo *rel,
+ Relids outer_relids, JoinType jointype)
{
- Var *pred_var,
- *clause_var;
- Const *pred_const,
- *clause_const;
- Oid pred_op,
- clause_op,
- test_op;
- Oid opclass_id = InvalidOid;
- StrategyNumber pred_strategy = 0,
- clause_strategy,
- test_strategy;
- Expr *test_expr;
- ExprState *test_exprstate;
- Datum test_result;
- bool isNull;
- Relation relation;
- HeapScanDesc scan;
- HeapTuple tuple;
- ScanKeyData entry[1];
- Form_pg_amop aform;
- EState *estate;
+ Path *cheapest;
+ bool isouterjoin;
+ List *clause_list;
+ List *indexpaths;
+ List *bitindexpaths;
+ ListCell *l;
+ InnerIndexscanInfo *info;
MemoryContext oldcontext;
- /* First try the equal() test */
- if (equal((Node *) predicate, clause))
- return true;
-
/*
- * Can't do anything more unless they are both binary opclauses with a
- * Var on the left and a Const on the right.
+ * Nestloop only supports inner, left, and IN joins.
*/
- if (!is_opclause(predicate))
- return false;
- pred_var = (Var *) get_leftop(predicate);
- pred_const = (Const *) get_rightop(predicate);
-
- if (!is_opclause(clause))
- return false;
- clause_var = (Var *) get_leftop((Expr *) clause);
- clause_const = (Const *) get_rightop((Expr *) clause);
-
- if (!IsA(clause_var, Var) ||
- clause_const == NULL ||
- !IsA(clause_const, Const) ||
- !IsA(pred_var, Var) ||
- pred_const == NULL ||
- !IsA(pred_const, Const))
- return false;
+ switch (jointype)
+ {
+ case JOIN_INNER:
+ case JOIN_IN:
+ case JOIN_UNIQUE_OUTER:
+ isouterjoin = false;
+ break;
+ case JOIN_LEFT:
+ isouterjoin = true;
+ break;
+ default:
+ return NULL;
+ }
/*
- * The implication can't be determined unless the predicate and the
- * clause refer to the same attribute.
+ * If there are no indexable joinclauses for this rel, exit quickly.
*/
- if (clause_var->varno != pred_var->varno ||
- clause_var->varattno != pred_var->varattno)
- return false;
-
- /* Get the operators for the two clauses we're comparing */
- pred_op = ((OpExpr *) predicate)->opno;
- clause_op = ((OpExpr *) clause)->opno;
+ if (bms_is_empty(rel->index_outer_relids))
+ return NULL;
/*
- * 1. Find a "btree" strategy number for the pred_op
- *
- * The following assumes that any given operator will only be in a single
- * btree operator class. This is true at least for all the
- * pre-defined operator classes. If it isn't true, then whichever
- * operator class happens to be returned first for the given operator
- * will be used to find the associated strategy numbers for the test.
- * --Nels, Jan '93
+ * Otherwise, we have to do path selection in the memory context of
+ * the given rel, so that any created path can be safely attached to
+ * the rel's cache of best inner paths. (This is not currently an
+ * issue for normal planning, but it is an issue for GEQO planning.)
*/
- ScanKeyEntryInitialize(&entry[0], 0x0,
- Anum_pg_amop_amopopr,
- F_OIDEQ,
- ObjectIdGetDatum(pred_op));
+ oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
- relation = heap_openr(AccessMethodOperatorRelationName, AccessShareLock);
- scan = heap_beginscan(relation, SnapshotNow, 1, entry);
+ /*
+ * Intersect the given outer_relids with index_outer_relids to find
+ * the set of outer relids actually relevant for this rel. If there
+ * are none, again we can fail immediately.
+ */
+ outer_relids = bms_intersect(rel->index_outer_relids, outer_relids);
+ if (bms_is_empty(outer_relids))
+ {
+ bms_free(outer_relids);
+ MemoryContextSwitchTo(oldcontext);
+ return NULL;
+ }
- while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
+ /*
+ * Look to see if we already computed the result for this set of
+ * relevant outerrels. (We include the isouterjoin status in the
+ * cache lookup key for safety. In practice I suspect this is not
+ * necessary because it should always be the same for a given
+ * innerrel.)
+ */
+ foreach(l, rel->index_inner_paths)
{
- aform = (Form_pg_amop) GETSTRUCT(tuple);
- if (opclass_is_btree(aform->amopclaid))
+ info = (InnerIndexscanInfo *) lfirst(l);
+ if (bms_equal(info->other_relids, outer_relids) &&
+ info->isouterjoin == isouterjoin)
{
- /* Get the predicate operator's btree strategy number (1 to 5) */
- pred_strategy = (StrategyNumber) aform->amopstrategy;
- Assert(pred_strategy >= 1 && pred_strategy <= 5);
-
- /*
- * Remember which operator class this strategy number came
- * from
- */
- opclass_id = aform->amopclaid;
- break;
+ bms_free(outer_relids);
+ MemoryContextSwitchTo(oldcontext);
+ return info->best_innerpath;
}
}
- heap_endscan(scan);
- heap_close(relation, AccessShareLock);
-
- if (!OidIsValid(opclass_id))
- {
- /* predicate operator isn't btree-indexable */
- return false;
- }
+ /*
+ * Find all the relevant restriction and join clauses.
+ */
+ clause_list = find_clauses_for_join(root, rel, outer_relids, isouterjoin);
/*
- * 2. From the same opclass, find a strategy num for the clause_op
+ * Find all the index paths that are usable for this join, except for
+ * stuff involving OR clauses.
*/
- tuple = SearchSysCache(AMOPOPID,
- ObjectIdGetDatum(opclass_id),
- ObjectIdGetDatum(clause_op),
- 0, 0);
- if (!HeapTupleIsValid(tuple))
- {
- /* clause operator isn't btree-indexable, or isn't in this opclass */
- return false;
- }
- aform = (Form_pg_amop) GETSTRUCT(tuple);
+ indexpaths = find_usable_indexes(root, rel,
+ clause_list, NIL,
+ false, true,
+ outer_relids);
- /* Get the restriction clause operator's strategy number (1 to 5) */
- clause_strategy = (StrategyNumber) aform->amopstrategy;
- Assert(clause_strategy >= 1 && clause_strategy <= 5);
+ /*
+ * Generate BitmapOrPaths for any suitable OR-clauses present in the
+ * clause list.
+ */
+ bitindexpaths = generate_bitmap_or_paths(root, rel,
+ clause_list, NIL,
+ true,
+ outer_relids);
- ReleaseSysCache(tuple);
+ /*
+ * Include the regular index paths in bitindexpaths.
+ */
+ bitindexpaths = list_concat(bitindexpaths, list_copy(indexpaths));
/*
- * 3. Look up the "test" strategy number in the implication table
+ * If we found anything usable, generate a BitmapHeapPath for the
+ * most promising combination of bitmap index paths.
*/
- test_strategy = BT_implic_table[clause_strategy - 1][pred_strategy - 1];
- if (test_strategy == 0)
+ if (bitindexpaths != NIL)
{
- return false; /* the implication cannot be determined */
+ Path *bitmapqual;
+ BitmapHeapPath *bpath;
+
+ bitmapqual = choose_bitmap_and(root, rel, bitindexpaths);
+ bpath = create_bitmap_heap_path(root, rel, bitmapqual, true);
+ indexpaths = lappend(indexpaths, bpath);
}
/*
- * 4. From the same opclass, find the operator for the test strategy
+ * Now choose the cheapest member of indexpaths.
*/
- tuple = SearchSysCache(AMOPSTRATEGY,
- ObjectIdGetDatum(opclass_id),
- Int16GetDatum(test_strategy),
- 0, 0);
- if (!HeapTupleIsValid(tuple))
+ cheapest = NULL;
+ foreach(l, indexpaths)
{
- /* this probably shouldn't fail? */
- elog(DEBUG1, "pred_test_simple_clause: unknown test_op");
- return false;
+ Path *path = (Path *) lfirst(l);
+
+ if (cheapest == NULL ||
+ compare_path_costs(path, cheapest, TOTAL_COST) < 0)
+ cheapest = path;
}
- aform = (Form_pg_amop) GETSTRUCT(tuple);
- /* Get the test operator */
- test_op = aform->amopopr;
+ /* Cache the result --- whether positive or negative */
+ info = makeNode(InnerIndexscanInfo);
+ info->other_relids = outer_relids;
+ info->isouterjoin = isouterjoin;
+ info->best_innerpath = cheapest;
+ rel->index_inner_paths = lcons(info, rel->index_inner_paths);
+
+ MemoryContextSwitchTo(oldcontext);
- ReleaseSysCache(tuple);
+ return cheapest;
+}
+
+/*
+ * find_clauses_for_join
+ * Generate a list of clauses that are potentially useful for
+ * scanning rel as the inner side of a nestloop join.
+ *
+ * We consider both join and restriction clauses. Any joinclause that uses
+ * only otherrels in the specified outer_relids is fair game. But there must
+ * be at least one such joinclause in the final list, otherwise we return NIL
+ * indicating that there isn't any potential win here.
+ */
+static List *
+find_clauses_for_join(PlannerInfo *root, RelOptInfo *rel,
+ Relids outer_relids, bool isouterjoin)
+{
+ List *clause_list = NIL;
+ bool jfound = false;
+ Relids join_relids;
+ ListCell *l;
/*
- * 5. Evaluate the test. For this we need an EState.
+ * We can always use plain restriction clauses for the rel. We
+ * scan these first because we want them first in the clause
+ * list for the convenience of remove_redundant_join_clauses,
+ * which can never remove non-join clauses and hence won't be able
+ * to get rid of a non-join clause if it appears after a join
+ * clause it is redundant with.
*/
- estate = CreateExecutorState();
+ foreach(l, rel->baserestrictinfo)
+ {
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
- /* We can use the estate's working context to avoid memory leaks. */
- oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
+ /* Can't use pushed-down clauses in outer join */
+ if (isouterjoin && rinfo->is_pushed_down)
+ continue;
+ clause_list = lappend(clause_list, rinfo);
+ }
- /* Build expression tree */
- test_expr = make_opclause(test_op,
- BOOLOID,
- false,
- (Expr *) clause_const,
- (Expr *) pred_const);
+ /* Look for joinclauses that are usable with given outer_relids */
+ join_relids = bms_union(rel->relids, outer_relids);
- /* Prepare it for execution */
- test_exprstate = ExecPrepareExpr(test_expr, estate);
+ foreach(l, rel->joininfo)
+ {
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
- /* And execute it. */
- test_result = ExecEvalExprSwitchContext(test_exprstate,
- GetPerTupleExprContext(estate),
- &isNull, NULL);
+ /* Can't use pushed-down clauses in outer join */
+ if (isouterjoin && rinfo->is_pushed_down)
+ continue;
+ if (!bms_is_subset(rinfo->required_relids, join_relids))
+ continue;
- /* Get back to outer memory context */
- MemoryContextSwitchTo(oldcontext);
+ clause_list = lappend(clause_list, rinfo);
+ jfound = true;
+ }
+
+ bms_free(join_relids);
- /* Release all the junk we just created */
- FreeExecutorState(estate);
+ /* if no join clause was matched then forget it, per comments above */
+ if (!jfound)
+ return NIL;
- if (isNull)
+ /*
+ * We may now have clauses that are known redundant. Get rid of 'em.
+ */
+ if (list_length(clause_list) > 1)
{
- elog(DEBUG1, "pred_test_simple_clause: null test result");
- return false;
+ clause_list = remove_redundant_join_clauses(root,
+ clause_list,
+ isouterjoin);
}
- return DatumGetBool(test_result);
-}
+ return clause_list;
+}
/****************************************************************************
- * ---- ROUTINES TO CHECK JOIN CLAUSES ----
+ * ---- ROUTINES TO HANDLE PATHKEYS ----
****************************************************************************/
/*
- * indexable_outerrelids
- * Finds all other relids that participate in any indexable join clause
- * for the specified index. Returns a list of relids.
+ * match_variant_ordering
+ * Try to match an index's ordering to the query's requested ordering
+ *
+ * This is used when the index is ordered but a naive comparison fails to
+ * match its ordering (pathkeys) to root->query_pathkeys. It may be that
+ * we need to scan the index backwards. Also, a less naive comparison can
+ * help for both forward and backward indexscans. Columns of the index
+ * that have an equality restriction clause can be ignored in the match;
+ * that is, an index on (x,y) can be considered to match the ordering of
+ * ... WHERE x = 42 ORDER BY y;
+ *
+ * Note: it would be possible to similarly ignore useless ORDER BY items;
+ * that is, an index on just y could be considered to match the ordering of
+ * ... WHERE x = 42 ORDER BY x, y;
+ * But proving that this is safe would require finding a btree opclass
+ * containing both the = operator and the < or > operator in the ORDER BY
+ * item. That's significantly more expensive than what we do here, since
+ * we'd have to look at restriction clauses unrelated to the current index
+ * and search for opclasses without any hint from the index. The practical
+ * use-cases seem to be mostly covered by ignoring index columns, so that's
+ * all we do for now.
*
- * 'rel' is the relation for which 'index' is defined
+ * Inputs:
+ * 'index' is the index of interest.
+ * 'restrictclauses' is the list of sublists of restriction clauses
+ * matching the columns of the index (NIL if none)
+ *
+ * If able to match the requested query pathkeys, returns either
+ * ForwardScanDirection or BackwardScanDirection to indicate the proper index
+ * scan direction. If no match, returns NoMovementScanDirection.
*/
-static Relids
-indexable_outerrelids(RelOptInfo *rel, IndexOptInfo *index)
+static ScanDirection
+match_variant_ordering(PlannerInfo *root,
+ IndexOptInfo *index,
+ List *restrictclauses)
+{
+ List *ignorables;
+
+ /*
+ * Forget the whole thing if not a btree index; our check for ignorable
+ * columns assumes we are dealing with btree opclasses. (It'd be possible
+ * to factor out just the try for backwards indexscan, but considering
+ * that we presently have no orderable indexes except btrees anyway,
+ * it's hardly worth contorting this code for that case.)
+ *
+ * Note: if you remove this, you probably need to put in a check on
+ * amoptionalkey to prevent possible clauseless scan on an index that
+ * won't cope.
+ */
+ if (index->relam != BTREE_AM_OID)
+ return NoMovementScanDirection;
+ /*
+ * Figure out which index columns can be optionally ignored because
+ * they have an equality constraint. This is the same set for either
+ * forward or backward scan, so we do it just once.
+ */
+ ignorables = identify_ignorable_ordering_cols(root, index,
+ restrictclauses);
+ /*
+ * Try to match to forward scan, then backward scan. However, we can
+ * skip the forward-scan case if there are no ignorable columns,
+ * because find_usable_indexes() would have found the match already.
+ */
+ if (ignorables &&
+ match_index_to_query_keys(root, index, ForwardScanDirection,
+ ignorables))
+ return ForwardScanDirection;
+
+ if (match_index_to_query_keys(root, index, BackwardScanDirection,
+ ignorables))
+ return BackwardScanDirection;
+
+ return NoMovementScanDirection;
+}
+
+/*
+ * identify_ignorable_ordering_cols
+ * Determine which index columns can be ignored for ordering purposes
+ *
+ * Returns an integer List of column numbers (1-based) of ignorable
+ * columns. The ignorable columns are those that have equality constraints
+ * against pseudoconstants.
+ */
+static List *
+identify_ignorable_ordering_cols(PlannerInfo *root,
+ IndexOptInfo *index,
+ List *restrictclauses)
{
- Relids outer_relids = NIL;
- List *i;
+ List *result = NIL;
+ int indexcol = 0; /* note this is 0-based */
+ ListCell *l;
- foreach(i, rel->joininfo)
+ /* restrictclauses is either NIL or has a sublist per column */
+ foreach(l, restrictclauses)
{
- JoinInfo *joininfo = (JoinInfo *) lfirst(i);
- bool match_found = false;
- List *j;
+ List *sublist = (List *) lfirst(l);
+ Oid opclass = index->classlist[indexcol];
+ ListCell *l2;
- /*
- * Examine each joinclause in the JoinInfo node's list to see if
- * it matches any key of the index. If so, add the JoinInfo's
- * otherrels to the result. We can skip examining other joinclauses
- * in the same list as soon as we find a match (since by definition
- * they all have the same otherrels).
- */
- foreach(j, joininfo->jinfo_restrictinfo)
+ foreach(l2, sublist)
{
- RestrictInfo *rinfo = (RestrictInfo *) lfirst(j);
- Expr *clause = rinfo->clause;
- int *indexkeys = index->indexkeys;
- Oid *classes = index->classlist;
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l2);
+ OpExpr *clause = (OpExpr *) rinfo->clause;
+ Oid clause_op;
+ int op_strategy;
+ bool varonleft;
+ bool ispc;
- do
+ /* We know this clause passed match_clause_to_indexcol */
+
+ /* First check for boolean-index cases. */
+ if (IsBooleanOpclass(opclass))
{
- int curIndxKey = indexkeys[0];
- Oid curClass = classes[0];
-
- if (match_join_clause_to_indexkey(rel,
- index,
- curIndxKey,
- curClass,
- clause))
+ if (match_boolean_index_clause((Node *) clause, indexcol,
+ index))
{
- match_found = true;
+ /*
+ * The clause means either col = TRUE or col = FALSE;
+ * we do not care which, it's an equality constraint
+ * either way.
+ */
+ result = lappend_int(result, indexcol+1);
break;
}
+ }
- indexkeys++;
- classes++;
+ /* Else clause must be a binary opclause. */
+ Assert(IsA(clause, OpExpr));
- } while (!DoneMatchingIndexKeys(indexkeys, classes));
+ /* Determine left/right sides and check the operator */
+ clause_op = clause->opno;
+ if (match_index_to_operand(linitial(clause->args), indexcol,
+ index))
+ {
+ /* clause_op is correct */
+ varonleft = true;
+ }
+ else
+ {
+ Assert(match_index_to_operand(lsecond(clause->args), indexcol,
+ index));
+ /* Must flip operator to get the opclass member */
+ clause_op = get_commutator(clause_op);
+ varonleft = false;
+ }
+ if (!OidIsValid(clause_op))
+ continue; /* ignore non match, per next comment */
+ op_strategy = get_op_opclass_strategy(clause_op, opclass);
- if (match_found)
- break;
- }
+ /*
+ * You might expect to see Assert(op_strategy != 0) here,
+ * but you won't: the clause might contain a special indexable
+ * operator rather than an ordinary opclass member. Currently
+ * none of the special operators are very likely to expand to
+ * an equality operator; we do not bother to check, but just
+ * assume no match.
+ */
+ if (op_strategy != BTEqualStrategyNumber)
+ continue;
- if (match_found)
- {
- outer_relids = set_unioni(outer_relids,
- joininfo->unjoined_relids);
+ /* Now check that other side is pseudoconstant */
+ if (varonleft)
+ ispc = is_pseudo_constant_clause_relids(lsecond(clause->args),
+ rinfo->right_relids);
+ else
+ ispc = is_pseudo_constant_clause_relids(linitial(clause->args),
+ rinfo->left_relids);
+ if (ispc)
+ {
+ result = lappend_int(result, indexcol+1);
+ break;
+ }
}
+ indexcol++;
}
-
- return outer_relids;
+ return result;
}
/*
- * best_inner_indexscan
- * Finds the best available inner indexscan for a nestloop join
- * with the given rel on the inside and the given outer_relids outside.
- * May return NULL if there are no possible inner indexscans.
+ * match_index_to_query_keys
+ * Check a single scan direction for "intelligent" match to query keys
*
- * We ignore ordering considerations (since a nestloop's inner scan's order
- * is uninteresting). Also, we consider only total cost when deciding which
- * of two possible paths is better --- this assumes that all indexpaths have
- * negligible startup cost. (True today, but someday we might have to think
- * harder.) Therefore, there is only one dimension of comparison and so it's
- * sufficient to return a single "best" path.
+ * 'index' is the index of interest.
+ * 'indexscandir' is the scan direction to consider
+ * 'ignorables' is an integer list of indexes of ignorable index columns
+ *
+ * Returns TRUE on successful match (ie, the query_pathkeys can be considered
+ * to match this index).
*/
-Path *
-best_inner_indexscan(Query *root, RelOptInfo *rel,
- Relids outer_relids, JoinType jointype)
+static bool
+match_index_to_query_keys(PlannerInfo *root,
+ IndexOptInfo *index,
+ ScanDirection indexscandir,
+ List *ignorables)
{
- Path *cheapest = NULL;
- bool isouterjoin;
- List *ilist;
- List *jlist;
- InnerIndexscanInfo *info;
- MemoryContext oldcontext;
-
- /*
- * Nestloop only supports inner and left joins.
- */
- switch (jointype)
- {
- case JOIN_INNER:
- isouterjoin = false;
- break;
- case JOIN_LEFT:
- isouterjoin = true;
- break;
- default:
- return NULL;
- }
- /*
- * If there are no indexable joinclauses for this rel, exit quickly.
- */
- if (!rel->index_outer_relids)
- return NULL;
- /*
- * Otherwise, we have to do path selection in the memory context of
- * the given rel, so that any created path can be safely attached to
- * the rel's cache of best inner paths. (This is not currently an
- * issue for normal planning, but it is an issue for GEQO planning.)
- */
- oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
- /*
- * Intersect the given outer_relids with index_outer_relids
- * to find the set of outer relids actually relevant for this index.
- * If there are none, again we can fail immediately.
- */
- outer_relids = set_intersecti(rel->index_outer_relids, outer_relids);
- if (!outer_relids)
- {
- MemoryContextSwitchTo(oldcontext);
- return NULL;
- }
- /*
- * Look to see if we already computed the result for this set of
- * relevant outerrels. (We include the isouterjoin status in the
- * cache lookup key for safety. In practice I suspect this is not
- * necessary because it should always be the same for a given innerrel.)
- */
- foreach(jlist, rel->index_inner_paths)
- {
- info = (InnerIndexscanInfo *) lfirst(jlist);
- if (sameseti(info->other_relids, outer_relids) &&
- info->isouterjoin == isouterjoin)
- {
- freeList(outer_relids);
- MemoryContextSwitchTo(oldcontext);
- return info->best_innerpath;
- }
- }
+ List *index_pathkeys;
+ ListCell *index_cell;
+ int index_col;
+ ListCell *r;
+
+ /* Get the pathkeys that exactly describe the index */
+ index_pathkeys = build_index_pathkeys(root, index, indexscandir);
/*
- * For each index of the rel, find the best path; then choose the
- * best overall. We cache the per-index results as well as the overall
- * result. (This is useful because different indexes may have different
- * relevant outerrel sets, so different overall outerrel sets might still
- * map to the same computation for a given index.)
+ * Can we match to the query's requested pathkeys? The inner loop
+ * skips over ignorable index columns while trying to match.
*/
- foreach(ilist, rel->indexlist)
+ index_cell = list_head(index_pathkeys);
+ index_col = 0;
+
+ foreach(r, root->query_pathkeys)
{
- IndexOptInfo *index = (IndexOptInfo *) lfirst(ilist);
- Relids index_outer_relids;
- Path *path = NULL;
+ List *rsubkey = (List *) lfirst(r);
- /* skip quickly if index has no useful join clauses */
- if (!index->outer_relids)
- continue;
- /* identify set of relevant outer relids for this index */
- index_outer_relids = set_intersecti(index->outer_relids, outer_relids);
- if (!index_outer_relids)
- continue;
- /*
- * Look to see if we already computed the result for this index.
- */
- foreach(jlist, index->inner_paths)
+ for (;;)
{
- info = (InnerIndexscanInfo *) lfirst(jlist);
- if (sameseti(info->other_relids, index_outer_relids) &&
- info->isouterjoin == isouterjoin)
- {
- path = info->best_innerpath;
- freeList(index_outer_relids); /* not needed anymore */
- break;
- }
- }
+ List *isubkey;
- if (jlist == NIL) /* failed to find a match? */
- {
- List *clausegroup;
-
- /* find useful clauses for this index and outerjoin set */
- clausegroup = group_clauses_by_indexkey_for_join(rel,
- index,
- index_outer_relids,
- isouterjoin);
- if (clausegroup)
- {
- /* remove duplicate and redundant clauses */
- clausegroup = remove_redundant_join_clauses(root,
- clausegroup,
- jointype);
- /* make the path */
- path = make_innerjoin_index_path(root, rel, index,
- clausegroup);
- }
+ if (index_cell == NULL)
+ return false;
+ isubkey = (List *) lfirst(index_cell);
+ index_cell = lnext(index_cell);
+ index_col++; /* index_col is now 1-based */
+ /*
+ * Since we are dealing with canonicalized pathkeys, pointer
+ * comparison is sufficient to determine a match.
+ */
+ if (rsubkey == isubkey)
+ break; /* matched current query pathkey */
- /* Cache the result --- whether positive or negative */
- info = makeNode(InnerIndexscanInfo);
- info->other_relids = index_outer_relids;
- info->isouterjoin = isouterjoin;
- info->best_innerpath = path;
- index->inner_paths = lcons(info, index->inner_paths);
+ if (!list_member_int(ignorables, index_col))
+ return false; /* definite failure to match */
+ /* otherwise loop around and try to match to next index col */
}
-
- if (path != NULL &&
- (cheapest == NULL ||
- compare_path_costs(path, cheapest, TOTAL_COST) < 0))
- cheapest = path;
}
- /* Cache the result --- whether positive or negative */
- info = makeNode(InnerIndexscanInfo);
- info->other_relids = outer_relids;
- info->isouterjoin = isouterjoin;
- info->best_innerpath = cheapest;
- rel->index_inner_paths = lcons(info, rel->index_inner_paths);
-
- MemoryContextSwitchTo(oldcontext);
-
- return cheapest;
+ return true;
}
/****************************************************************************
****************************************************************************/
/*
- * make_innerjoin_index_path
- * Create an index path node for a path to be used as an inner
- * relation in a nestloop join.
+ * flatten_clausegroups_list
+ * Given a list of lists of RestrictInfos, flatten it to a list
+ * of RestrictInfos.
*
- * 'rel' is the relation for which 'index' is defined
- * 'clausegroup' is a list of restrictinfo nodes that can use 'index'
+ * This is used to flatten out the result of group_clauses_by_indexkey()
+ * to produce an indexclauses list. The original list structure mustn't
+ * be altered, but it's OK to share copies of the underlying RestrictInfos.
*/
-static Path *
-make_innerjoin_index_path(Query *root,
- RelOptInfo *rel, IndexOptInfo *index,
- List *clausegroup)
+List *
+flatten_clausegroups_list(List *clausegroups)
{
- IndexPath *pathnode = makeNode(IndexPath);
- List *indexquals;
+ List *allclauses = NIL;
+ ListCell *l;
- /* XXX this code ought to be merged with create_index_path? */
-
- pathnode->path.pathtype = T_IndexScan;
- pathnode->path.parent = rel;
-
- /*
- * There's no point in marking the path with any pathkeys, since
- * it will only ever be used as the inner path of a nestloop, and
- * so its ordering does not matter.
- */
- pathnode->path.pathkeys = NIL;
-
- /* Extract bare indexqual clauses from restrictinfos */
- indexquals = get_actual_clauses(clausegroup);
-
- /* expand special operators to indexquals the executor can handle */
- indexquals = expand_indexqual_conditions(indexquals);
-
- /*
- * Note that we are making a pathnode for a single-scan indexscan;
- * therefore, both indexinfo and indexqual should be single-element lists.
- */
- pathnode->indexinfo = makeList1(index);
- pathnode->indexqual = makeList1(indexquals);
-
- /* We don't actually care what order the index scans in ... */
- pathnode->indexscandir = NoMovementScanDirection;
-
- /*
- * We must compute the estimated number of output rows for the
- * indexscan. This is less than rel->rows because of the
- * additional selectivity of the join clauses. Since clausegroup
- * may contain both restriction and join clauses, we have to do a
- * set union to get the full set of clauses that must be
- * considered to compute the correct selectivity. (We can't just
- * nconc the two lists; then we might have some restriction
- * clauses appearing twice, which'd mislead
- * restrictlist_selectivity into double-counting their
- * selectivity.)
- */
- pathnode->rows = rel->tuples *
- restrictlist_selectivity(root,
- set_union(rel->baserestrictinfo,
- clausegroup),
- lfirsti(rel->relids));
- /* Like costsize.c, force estimate to be at least one row */
- if (pathnode->rows < 1.0)
- pathnode->rows = 1.0;
-
- cost_index(&pathnode->path, root, rel, index, indexquals, true);
-
- return (Path *) pathnode;
+ foreach(l, clausegroups)
+ allclauses = list_concat(allclauses, list_copy((List *) lfirst(l)));
+ return allclauses;
}
+
/****************************************************************************
* ---- 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.
+ *
+ * operand: the nodetree to be compared to the index
+ * indexcol: the column number of the index (counting from 0)
+ * index: the index of interest
*/
-static bool
-match_index_to_operand(int indexkey,
- Node *operand,
- RelOptInfo *rel,
+bool
+match_index_to_operand(Node *operand,
+ int indexcol,
IndexOptInfo *index)
{
+ int indkey;
+
/*
- * Ignore any RelabelType node above the indexkey. This is needed to
+ * Ignore any RelabelType node above the operand. This is needed to
* be able to apply indexscanning in binary-compatible-operator cases.
* Note: we can assume there is at most one RelabelType node;
* eval_const_expressions() will have simplified if more than one.
if (operand && IsA(operand, RelabelType))
operand = (Node *) ((RelabelType *) operand)->arg;
- if (index->indproc == InvalidOid)
+ indkey = index->indexkeys[indexcol];
+ if (indkey != 0)
{
/*
- * Simple index.
+ * Simple index column; operand must be a matching Var.
*/
if (operand && IsA(operand, Var) &&
- lfirsti(rel->relids) == ((Var *) operand)->varno &&
- indexkey == ((Var *) operand)->varattno)
+ index->rel->relid == ((Var *) operand)->varno &&
+ indkey == ((Var *) operand)->varattno)
return true;
- else
- return false;
}
+ else
+ {
+ /*
+ * Index expression; find the correct expression. (This search
+ * could be avoided, at the cost of complicating all the callers
+ * of this routine; doesn't seem worth it.)
+ */
+ ListCell *indexpr_item;
+ int i;
+ Node *indexkey;
- /*
- * Functional index.
- */
- return function_index_operand((Expr *) operand, rel, index);
-}
-
-static bool
-function_index_operand(Expr *funcOpnd, RelOptInfo *rel, IndexOptInfo *index)
-{
- int relvarno = lfirsti(rel->relids);
- FuncExpr *function;
- List *funcargs;
- int *indexKeys = index->indexkeys;
- List *arg;
- int i;
-
- /*
- * sanity check, make sure we know what we're dealing with here.
- */
- if (funcOpnd == NULL || !IsA(funcOpnd, FuncExpr) ||
- indexKeys == NULL)
- return false;
-
- function = (FuncExpr *) funcOpnd;
- funcargs = function->args;
+ indexpr_item = list_head(index->indexprs);
+ for (i = 0; i < indexcol; i++)
+ {
+ if (index->indexkeys[i] == 0)
+ {
+ if (indexpr_item == NULL)
+ elog(ERROR, "wrong number of index expressions");
+ indexpr_item = lnext(indexpr_item);
+ }
+ }
+ if (indexpr_item == NULL)
+ elog(ERROR, "wrong number of index expressions");
+ indexkey = (Node *) lfirst(indexpr_item);
- if (function->funcid != index->indproc)
- return false;
+ /*
+ * Does it match the operand? Again, strip any relabeling.
+ */
+ if (indexkey && IsA(indexkey, RelabelType))
+ indexkey = (Node *) ((RelabelType *) indexkey)->arg;
- /*----------
- * Check that the arguments correspond to the same arguments used to
- * create the functional index. To do this we must check that
- * 1. they refer to the right relation.
- * 2. the args have the right attr. numbers in the right order.
- * We must ignore RelabelType nodes above the argument Vars in order
- * to recognize binary-compatible-function cases correctly.
- *----------
- */
- i = 0;
- foreach(arg, funcargs)
- {
- Var *var = (Var *) lfirst(arg);
-
- if (var && IsA(var, RelabelType))
- var = (Var *) ((RelabelType *) var)->arg;
- if (var == NULL || !IsA(var, Var))
- return false;
- if (indexKeys[i] == 0)
- return false;
- if (var->varno != relvarno || var->varattno != indexKeys[i])
- return false;
-
- i++;
+ if (equal(indexkey, operand))
+ return true;
}
- if (indexKeys[i] != 0)
- return false; /* not enough arguments */
-
- return true;
+ return false;
}
/****************************************************************************
* from LIKE to indexscan limits rather harder than one might think ...
* but that's the basic idea.)
*
- * Two routines are provided here, match_special_index_operator() and
- * expand_indexqual_conditions(). match_special_index_operator() is
- * just an auxiliary function for match_clause_to_indexkey(); after
- * the latter fails to recognize a restriction opclause's operator
- * as a member of an index's opclass, it asks match_special_index_operator()
- * whether the clause should be considered an indexqual anyway.
- * expand_indexqual_conditions() converts a list of "raw" indexqual
- * conditions (with implicit AND semantics across list elements) into
- * a list that the executor can actually handle. For operators that
- * are members of the index's opclass this transformation is a no-op,
- * but operators recognized by match_special_index_operator() must be
- * converted into one or more "regular" indexqual conditions.
+ * Another thing that we do with this machinery is to provide special
+ * smarts for "boolean" indexes (that is, indexes on boolean columns
+ * that support boolean equality). We can transform a plain reference
+ * to the indexkey into "indexkey = true", or "NOT indexkey" into
+ * "indexkey = false", so as to make the expression indexable using the
+ * regular index operators. (As of Postgres 8.1, we must do this here
+ * because constant simplification does the reverse transformation;
+ * without this code there'd be no way to use such an index at all.)
+ *
+ * Three routines are provided here:
+ *
+ * match_special_index_operator() is just an auxiliary function for
+ * match_clause_to_indexcol(); after the latter fails to recognize a
+ * restriction opclause's operator as a member of an index's opclass,
+ * it asks match_special_index_operator() whether the clause should be
+ * considered an indexqual anyway.
+ *
+ * match_boolean_index_clause() similarly detects clauses that can be
+ * converted into boolean equality operators.
+ *
+ * expand_indexqual_conditions() converts a list of lists of RestrictInfo
+ * nodes (with implicit AND semantics across list elements) into
+ * a list of clauses that the executor can actually handle. For operators
+ * that are members of the index's opclass this transformation is a no-op,
+ * but clauses recognized by match_special_index_operator() or
+ * match_boolean_index_clause() must be converted into one or more "regular"
+ * indexqual conditions.
*----------
*/
+/*
+ * match_boolean_index_clause
+ * Recognize restriction clauses that can be matched to a boolean index.
+ *
+ * This should be called only when IsBooleanOpclass() recognizes the
+ * index's operator class. We check to see if the clause matches the
+ * index's key.
+ */
+static bool
+match_boolean_index_clause(Node *clause,
+ int indexcol,
+ IndexOptInfo *index)
+{
+ /* Direct match? */
+ if (match_index_to_operand(clause, indexcol, index))
+ return true;
+ /* NOT clause? */
+ if (not_clause(clause))
+ {
+ if (match_index_to_operand((Node *) get_notclausearg((Expr *) clause),
+ indexcol, index))
+ return true;
+ }
+ /*
+ * Since we only consider clauses at top level of WHERE, we can convert
+ * indexkey IS TRUE and indexkey IS FALSE to index searches as well.
+ * The different meaning for NULL isn't important.
+ */
+ else if (clause && IsA(clause, BooleanTest))
+ {
+ BooleanTest *btest = (BooleanTest *) clause;
+
+ if (btest->booltesttype == IS_TRUE ||
+ btest->booltesttype == IS_FALSE)
+ if (match_index_to_operand((Node *) btest->arg,
+ indexcol, index))
+ return true;
+ }
+ return false;
+}
+
/*
* match_special_index_operator
* Recognize restriction clauses that can be used to generate
bool indexkey_on_left)
{
bool isIndexable = false;
- Node *leftop,
- *rightop;
+ Node *rightop;
Oid expr_op;
- Const *patt = NULL;
+ Const *patt;
Const *prefix = NULL;
Const *rest = NULL;
return false;
/* we know these will succeed */
- leftop = get_leftop(clause);
rightop = get_rightop(clause);
expr_op = ((OpExpr *) clause)->opno;
{
case OID_TEXT_LIKE_OP:
case OID_BPCHAR_LIKE_OP:
- case OID_VARCHAR_LIKE_OP:
case OID_NAME_LIKE_OP:
/* the right-hand const is type text for all of these */
- if (locale_is_like_safe())
- isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Like,
+ isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Like,
&prefix, &rest) != Pattern_Prefix_None;
break;
case OID_TEXT_ICLIKE_OP:
case OID_BPCHAR_ICLIKE_OP:
- case OID_VARCHAR_ICLIKE_OP:
case OID_NAME_ICLIKE_OP:
/* the right-hand const is type text for all of these */
- if (locale_is_like_safe())
- isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Like_IC,
+ isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Like_IC,
&prefix, &rest) != Pattern_Prefix_None;
break;
case OID_TEXT_REGEXEQ_OP:
case OID_BPCHAR_REGEXEQ_OP:
- case OID_VARCHAR_REGEXEQ_OP:
case OID_NAME_REGEXEQ_OP:
/* the right-hand const is type text for all of these */
- if (locale_is_like_safe())
- isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Regex,
+ isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Regex,
&prefix, &rest) != Pattern_Prefix_None;
break;
case OID_TEXT_ICREGEXEQ_OP:
case OID_BPCHAR_ICREGEXEQ_OP:
- case OID_VARCHAR_ICREGEXEQ_OP:
case OID_NAME_ICREGEXEQ_OP:
/* the right-hand const is type text for all of these */
- if (locale_is_like_safe())
- isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Regex_IC,
+ isIndexable = pattern_fixed_prefix(patt, Pattern_Type_Regex_IC,
&prefix, &rest) != Pattern_Prefix_None;
break;
/*
* Must also check that index's opclass supports the operators we will
* want to apply. (A hash index, for example, will not support ">=".)
- * We cheat a little by not checking for availability of "=" ... any
- * index type should support "=", methinks.
+ * Currently, only btree supports the operators we need.
+ *
+ * We insist on the opclass being the specific one we expect, else we'd
+ * do the wrong thing if someone were to make a reverse-sort opclass
+ * with the same operators.
*/
switch (expr_op)
{
case OID_TEXT_ICLIKE_OP:
case OID_TEXT_REGEXEQ_OP:
case OID_TEXT_ICREGEXEQ_OP:
- if (!op_in_opclass(find_operator(">=", TEXTOID), opclass) ||
- !op_in_opclass(find_operator("<", TEXTOID), opclass))
- isIndexable = false;
- break;
-
- case OID_BYTEA_LIKE_OP:
- if (!op_in_opclass(find_operator(">=", BYTEAOID), opclass) ||
- !op_in_opclass(find_operator("<", BYTEAOID), opclass))
- isIndexable = false;
+ /* text operators will be used for varchar inputs, too */
+ isIndexable =
+ (opclass == TEXT_PATTERN_BTREE_OPS_OID) ||
+ (opclass == TEXT_BTREE_OPS_OID && lc_collate_is_c()) ||
+ (opclass == VARCHAR_PATTERN_BTREE_OPS_OID) ||
+ (opclass == VARCHAR_BTREE_OPS_OID && lc_collate_is_c());
break;
case OID_BPCHAR_LIKE_OP:
case OID_BPCHAR_ICLIKE_OP:
case OID_BPCHAR_REGEXEQ_OP:
case OID_BPCHAR_ICREGEXEQ_OP:
- if (!op_in_opclass(find_operator(">=", BPCHAROID), opclass) ||
- !op_in_opclass(find_operator("<", BPCHAROID), opclass))
- isIndexable = false;
- break;
-
- case OID_VARCHAR_LIKE_OP:
- case OID_VARCHAR_ICLIKE_OP:
- case OID_VARCHAR_REGEXEQ_OP:
- case OID_VARCHAR_ICREGEXEQ_OP:
- if (!op_in_opclass(find_operator(">=", VARCHAROID), opclass) ||
- !op_in_opclass(find_operator("<", VARCHAROID), opclass))
- isIndexable = false;
+ isIndexable =
+ (opclass == BPCHAR_PATTERN_BTREE_OPS_OID) ||
+ (opclass == BPCHAR_BTREE_OPS_OID && lc_collate_is_c());
break;
case OID_NAME_LIKE_OP:
case OID_NAME_ICLIKE_OP:
case OID_NAME_REGEXEQ_OP:
case OID_NAME_ICREGEXEQ_OP:
- if (!op_in_opclass(find_operator(">=", NAMEOID), opclass) ||
- !op_in_opclass(find_operator("<", NAMEOID), opclass))
- isIndexable = false;
+ isIndexable =
+ (opclass == NAME_PATTERN_BTREE_OPS_OID) ||
+ (opclass == NAME_BTREE_OPS_OID && lc_collate_is_c());
+ break;
+
+ case OID_BYTEA_LIKE_OP:
+ isIndexable = (opclass == BYTEA_BTREE_OPS_OID);
break;
case OID_INET_SUB_OP:
case OID_INET_SUBEQ_OP:
- /* for SUB we actually need ">" not ">=", but this should do */
- if (!op_in_opclass(find_operator(">=", INETOID), opclass) ||
- !op_in_opclass(find_operator("<=", INETOID), opclass))
- isIndexable = false;
+ isIndexable = (opclass == INET_BTREE_OPS_OID);
break;
case OID_CIDR_SUB_OP:
case OID_CIDR_SUBEQ_OP:
- /* for SUB we actually need ">" not ">=", but this should do */
- if (!op_in_opclass(find_operator(">=", CIDROID), opclass) ||
- !op_in_opclass(find_operator("<=", CIDROID), opclass))
- isIndexable = false;
+ isIndexable = (opclass == CIDR_BTREE_OPS_OID);
break;
}
/*
* expand_indexqual_conditions
- * Given a list of (implicitly ANDed) indexqual clauses,
- * expand any "special" index operators into clauses that the indexscan
- * machinery will know what to do with. Clauses that were not
- * recognized by match_special_index_operator() must be passed through
- * unchanged.
+ * Given a list of sublists of RestrictInfo nodes, produce a flat list
+ * of index qual clauses. Standard qual clauses (those in the index's
+ * opclass) are passed through unchanged. Boolean clauses and "special"
+ * index operators are expanded into clauses that the indexscan machinery
+ * will know what to do with.
+ *
+ * The input list is ordered by index key, and so the output list is too.
+ * (The latter is not depended on by any part of the core planner, I believe,
+ * but parts of the executor require it, and so do the amcostestimate
+ * functions.)
*/
List *
-expand_indexqual_conditions(List *indexquals)
+expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups)
{
List *resultquals = NIL;
- List *q;
+ ListCell *clausegroup_item;
+ int indexcol = 0;
+ Oid *classes = index->classlist;
+
+ if (clausegroups == NIL)
+ return NIL;
- foreach(q, indexquals)
+ clausegroup_item = list_head(clausegroups);
+ do
{
- Expr *clause = (Expr *) lfirst(q);
-
- /* we know these will succeed */
- Node *leftop = get_leftop(clause);
- Node *rightop = get_rightop(clause);
- Oid expr_op = ((OpExpr *) clause)->opno;
- Const *patt = (Const *) rightop;
- Const *prefix = NULL;
- Const *rest = NULL;
- Pattern_Prefix_Status pstatus;
-
- switch (expr_op)
+ Oid curClass = classes[0];
+ ListCell *l;
+
+ foreach(l, (List *) lfirst(clausegroup_item))
{
- /*
- * LIKE and regex operators are not members of any index
- * opclass, so if we find one in an indexqual list we can
- * assume that it was accepted by
- * match_special_index_operator().
- */
- case OID_TEXT_LIKE_OP:
- case OID_BPCHAR_LIKE_OP:
- case OID_VARCHAR_LIKE_OP:
- case OID_NAME_LIKE_OP:
- case OID_BYTEA_LIKE_OP:
- pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like,
- &prefix, &rest);
- resultquals = nconc(resultquals,
- prefix_quals(leftop, expr_op,
- prefix, pstatus));
- break;
+ RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
- case OID_TEXT_ICLIKE_OP:
- case OID_BPCHAR_ICLIKE_OP:
- case OID_VARCHAR_ICLIKE_OP:
- case OID_NAME_ICLIKE_OP:
- /* the right-hand const is type text for all of these */
- pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like_IC,
- &prefix, &rest);
- resultquals = nconc(resultquals,
- prefix_quals(leftop, expr_op,
- prefix, pstatus));
- break;
+ /* First check for boolean cases */
+ if (IsBooleanOpclass(curClass))
+ {
+ Expr *boolqual;
- case OID_TEXT_REGEXEQ_OP:
- case OID_BPCHAR_REGEXEQ_OP:
- case OID_VARCHAR_REGEXEQ_OP:
- case OID_NAME_REGEXEQ_OP:
- /* the right-hand const is type text for all of these */
- pstatus = pattern_fixed_prefix(patt, Pattern_Type_Regex,
- &prefix, &rest);
- resultquals = nconc(resultquals,
- prefix_quals(leftop, expr_op,
- prefix, pstatus));
- break;
+ boolqual = expand_boolean_index_clause((Node *) rinfo->clause,
+ indexcol,
+ index);
+ if (boolqual)
+ {
+ resultquals = lappend(resultquals,
+ make_restrictinfo(boolqual,
+ true,
+ NULL));
+ continue;
+ }
+ }
- case OID_TEXT_ICREGEXEQ_OP:
- case OID_BPCHAR_ICREGEXEQ_OP:
- case OID_VARCHAR_ICREGEXEQ_OP:
- case OID_NAME_ICREGEXEQ_OP:
- /* the right-hand const is type text for all of these */
- pstatus = pattern_fixed_prefix(patt, Pattern_Type_Regex_IC,
- &prefix, &rest);
- resultquals = nconc(resultquals,
- prefix_quals(leftop, expr_op,
- prefix, pstatus));
- break;
+ resultquals = list_concat(resultquals,
+ expand_indexqual_condition(rinfo,
+ curClass));
+ }
- case OID_INET_SUB_OP:
- case OID_INET_SUBEQ_OP:
- case OID_CIDR_SUB_OP:
- case OID_CIDR_SUBEQ_OP:
- resultquals = nconc(resultquals,
- network_prefix_quals(leftop, expr_op,
- patt->constvalue));
- break;
+ clausegroup_item = lnext(clausegroup_item);
- default:
- resultquals = lappend(resultquals, clause);
- break;
+ indexcol++;
+ classes++;
+ } while (clausegroup_item != NULL && !DoneMatchingIndexKeys(classes));
+
+ Assert(clausegroup_item == NULL); /* else more groups than indexkeys */
+
+ return resultquals;
+}
+
+/*
+ * expand_boolean_index_clause
+ * Convert a clause recognized by match_boolean_index_clause into
+ * a boolean equality operator clause.
+ *
+ * Returns NULL if the clause isn't a boolean index qual.
+ */
+static Expr *
+expand_boolean_index_clause(Node *clause,
+ int indexcol,
+ IndexOptInfo *index)
+{
+ /* Direct match? */
+ if (match_index_to_operand(clause, indexcol, index))
+ {
+ /* convert to indexkey = TRUE */
+ return make_opclause(BooleanEqualOperator, BOOLOID, false,
+ (Expr *) clause,
+ (Expr *) makeBoolConst(true, false));
+ }
+ /* NOT clause? */
+ if (not_clause(clause))
+ {
+ Node *arg = (Node *) get_notclausearg((Expr *) clause);
+
+ /* It must have matched the indexkey */
+ Assert(match_index_to_operand(arg, indexcol, index));
+ /* convert to indexkey = FALSE */
+ return make_opclause(BooleanEqualOperator, BOOLOID, false,
+ (Expr *) arg,
+ (Expr *) makeBoolConst(false, false));
+ }
+ if (clause && IsA(clause, BooleanTest))
+ {
+ BooleanTest *btest = (BooleanTest *) clause;
+ Node *arg = (Node *) btest->arg;
+
+ /* It must have matched the indexkey */
+ Assert(match_index_to_operand(arg, indexcol, index));
+ if (btest->booltesttype == IS_TRUE)
+ {
+ /* convert to indexkey = TRUE */
+ return make_opclause(BooleanEqualOperator, BOOLOID, false,
+ (Expr *) arg,
+ (Expr *) makeBoolConst(true, false));
}
+ if (btest->booltesttype == IS_FALSE)
+ {
+ /* convert to indexkey = FALSE */
+ return make_opclause(BooleanEqualOperator, BOOLOID, false,
+ (Expr *) arg,
+ (Expr *) makeBoolConst(false, false));
+ }
+ /* Oops */
+ Assert(false);
}
- return resultquals;
+ return NULL;
+}
+
+/*
+ * expand_indexqual_condition --- expand a single indexqual condition
+ * (other than a boolean-qual case)
+ *
+ * The input is a single RestrictInfo, the output a list of RestrictInfos
+ */
+static List *
+expand_indexqual_condition(RestrictInfo *rinfo, Oid opclass)
+{
+ Expr *clause = rinfo->clause;
+ /* we know these will succeed */
+ Node *leftop = get_leftop(clause);
+ Node *rightop = get_rightop(clause);
+ Oid expr_op = ((OpExpr *) clause)->opno;
+ Const *patt = (Const *) rightop;
+ Const *prefix = NULL;
+ Const *rest = NULL;
+ Pattern_Prefix_Status pstatus;
+ List *result;
+
+ switch (expr_op)
+ {
+ /*
+ * LIKE and regex operators are not members of any index
+ * opclass, so if we find one in an indexqual list we can
+ * assume that it was accepted by
+ * match_special_index_operator().
+ */
+ case OID_TEXT_LIKE_OP:
+ case OID_BPCHAR_LIKE_OP:
+ case OID_NAME_LIKE_OP:
+ case OID_BYTEA_LIKE_OP:
+ pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like,
+ &prefix, &rest);
+ result = prefix_quals(leftop, opclass, prefix, pstatus);
+ break;
+
+ case OID_TEXT_ICLIKE_OP:
+ case OID_BPCHAR_ICLIKE_OP:
+ case OID_NAME_ICLIKE_OP:
+ /* the right-hand const is type text for all of these */
+ pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like_IC,
+ &prefix, &rest);
+ result = prefix_quals(leftop, opclass, prefix, pstatus);
+ break;
+
+ case OID_TEXT_REGEXEQ_OP:
+ case OID_BPCHAR_REGEXEQ_OP:
+ case OID_NAME_REGEXEQ_OP:
+ /* the right-hand const is type text for all of these */
+ pstatus = pattern_fixed_prefix(patt, Pattern_Type_Regex,
+ &prefix, &rest);
+ result = prefix_quals(leftop, opclass, prefix, pstatus);
+ break;
+
+ case OID_TEXT_ICREGEXEQ_OP:
+ case OID_BPCHAR_ICREGEXEQ_OP:
+ case OID_NAME_ICREGEXEQ_OP:
+ /* the right-hand const is type text for all of these */
+ pstatus = pattern_fixed_prefix(patt, Pattern_Type_Regex_IC,
+ &prefix, &rest);
+ result = prefix_quals(leftop, opclass, prefix, pstatus);
+ break;
+
+ case OID_INET_SUB_OP:
+ case OID_INET_SUBEQ_OP:
+ case OID_CIDR_SUB_OP:
+ case OID_CIDR_SUBEQ_OP:
+ result = network_prefix_quals(leftop, expr_op, opclass,
+ patt->constvalue);
+ break;
+
+ default:
+ result = list_make1(rinfo);
+ break;
+ }
+
+ return result;
}
/*
* Given a fixed prefix that all the "leftop" values must have,
- * generate suitable indexqual condition(s). expr_op is the original
- * LIKE or regex operator; we use it to deduce the appropriate comparison
- * operators.
+ * generate suitable indexqual condition(s). opclass is the index
+ * operator class; we use it to deduce the appropriate comparison
+ * operators and operand datatypes.
*/
static List *
-prefix_quals(Node *leftop, Oid expr_op,
+prefix_quals(Node *leftop, Oid opclass,
Const *prefix_const, Pattern_Prefix_Status pstatus)
{
List *result;
Oid datatype;
Oid oproid;
- char *prefix;
- Const *con;
Expr *expr;
- Const *greaterstr = NULL;
+ Const *greaterstr;
Assert(pstatus != Pattern_Prefix_None);
- switch (expr_op)
+ switch (opclass)
{
- case OID_TEXT_LIKE_OP:
- case OID_TEXT_ICLIKE_OP:
- case OID_TEXT_REGEXEQ_OP:
- case OID_TEXT_ICREGEXEQ_OP:
+ case TEXT_BTREE_OPS_OID:
+ case TEXT_PATTERN_BTREE_OPS_OID:
datatype = TEXTOID;
break;
- case OID_BYTEA_LIKE_OP:
- datatype = BYTEAOID;
+ case VARCHAR_BTREE_OPS_OID:
+ case VARCHAR_PATTERN_BTREE_OPS_OID:
+ datatype = VARCHAROID;
break;
- case OID_BPCHAR_LIKE_OP:
- case OID_BPCHAR_ICLIKE_OP:
- case OID_BPCHAR_REGEXEQ_OP:
- case OID_BPCHAR_ICREGEXEQ_OP:
+ case BPCHAR_BTREE_OPS_OID:
+ case BPCHAR_PATTERN_BTREE_OPS_OID:
datatype = BPCHAROID;
break;
- case OID_VARCHAR_LIKE_OP:
- case OID_VARCHAR_ICLIKE_OP:
- case OID_VARCHAR_REGEXEQ_OP:
- case OID_VARCHAR_ICREGEXEQ_OP:
- datatype = VARCHAROID;
+ case NAME_BTREE_OPS_OID:
+ case NAME_PATTERN_BTREE_OPS_OID:
+ datatype = NAMEOID;
break;
- case OID_NAME_LIKE_OP:
- case OID_NAME_ICLIKE_OP:
- case OID_NAME_REGEXEQ_OP:
- case OID_NAME_ICREGEXEQ_OP:
- datatype = NAMEOID;
+ case BYTEA_BTREE_OPS_OID:
+ datatype = BYTEAOID;
break;
default:
- elog(ERROR, "prefix_quals: unexpected operator %u", expr_op);
+ /* shouldn't get here */
+ elog(ERROR, "unexpected opclass: %u", opclass);
return NIL;
}
- if (prefix_const->consttype != BYTEAOID)
- prefix = DatumGetCString(DirectFunctionCall1(textout, prefix_const->constvalue));
- else
- prefix = DatumGetCString(DirectFunctionCall1(byteaout, prefix_const->constvalue));
+ /*
+ * If necessary, coerce the prefix constant to the right type. The
+ * given prefix constant is either text or bytea type.
+ */
+ if (prefix_const->consttype != datatype)
+ {
+ char *prefix;
+
+ switch (prefix_const->consttype)
+ {
+ case TEXTOID:
+ prefix = DatumGetCString(DirectFunctionCall1(textout,
+ prefix_const->constvalue));
+ break;
+ case BYTEAOID:
+ prefix = DatumGetCString(DirectFunctionCall1(byteaout,
+ prefix_const->constvalue));
+ break;
+ default:
+ elog(ERROR, "unexpected const type: %u",
+ prefix_const->consttype);
+ return NIL;
+ }
+ prefix_const = string_to_const(prefix, datatype);
+ pfree(prefix);
+ }
/*
* If we found an exact-match pattern, generate an "=" indexqual.
*/
if (pstatus == Pattern_Prefix_Exact)
{
- oproid = find_operator("=", datatype);
+ oproid = get_opclass_member(opclass, InvalidOid,
+ BTEqualStrategyNumber);
if (oproid == InvalidOid)
- elog(ERROR, "prefix_quals: no = operator for type %u", datatype);
- con = string_to_const(prefix, datatype);
+ elog(ERROR, "no = operator for opclass %u", opclass);
expr = make_opclause(oproid, BOOLOID, false,
- (Expr *) leftop, (Expr *) con);
- result = makeList1(expr);
+ (Expr *) leftop, (Expr *) prefix_const);
+ result = list_make1(make_restrictinfo(expr, true, NULL));
return result;
}
*
* We can always say "x >= prefix".
*/
- oproid = find_operator(">=", datatype);
+ oproid = get_opclass_member(opclass, InvalidOid,
+ BTGreaterEqualStrategyNumber);
if (oproid == InvalidOid)
- elog(ERROR, "prefix_quals: no >= operator for type %u", datatype);
- con = string_to_const(prefix, datatype);
+ elog(ERROR, "no >= operator for opclass %u", opclass);
expr = make_opclause(oproid, BOOLOID, false,
- (Expr *) leftop, (Expr *) con);
- result = makeList1(expr);
+ (Expr *) leftop, (Expr *) prefix_const);
+ result = list_make1(make_restrictinfo(expr, true, NULL));
/*-------
* If we can create a string larger than the prefix, we can say
* "x < greaterstr".
*-------
*/
- greaterstr = make_greater_string(con);
+ greaterstr = make_greater_string(prefix_const);
if (greaterstr)
{
- oproid = find_operator("<", datatype);
+ oproid = get_opclass_member(opclass, InvalidOid,
+ BTLessStrategyNumber);
if (oproid == InvalidOid)
- elog(ERROR, "prefix_quals: no < operator for type %u", datatype);
+ elog(ERROR, "no < operator for opclass %u", opclass);
expr = make_opclause(oproid, BOOLOID, false,
(Expr *) leftop, (Expr *) greaterstr);
- result = lappend(result, expr);
+ result = lappend(result, make_restrictinfo(expr, true, NULL));
}
return result;
/*
* Given a leftop and a rightop, and a inet-class sup/sub operator,
* generate suitable indexqual condition(s). expr_op is the original
- * operator.
+ * operator, and opclass is the index opclass.
*/
static List *
-network_prefix_quals(Node *leftop, Oid expr_op, Datum rightop)
+network_prefix_quals(Node *leftop, Oid expr_op, Oid opclass, Datum rightop)
{
bool is_eq;
- char *opr1name;
- Datum opr1right;
- Datum opr2right;
+ Oid datatype;
Oid opr1oid;
Oid opr2oid;
+ Datum opr1right;
+ Datum opr2right;
List *result;
- Oid datatype;
Expr *expr;
switch (expr_op)
is_eq = true;
break;
default:
- elog(ERROR, "network_prefix_quals: unexpected operator %u",
- expr_op);
+ elog(ERROR, "unexpected operator: %u", expr_op);
return NIL;
}
* create clause "key >= network_scan_first( rightop )", or ">" if the
* operator disallows equality.
*/
-
- opr1name = is_eq ? ">=" : ">";
- opr1oid = find_operator(opr1name, datatype);
- if (opr1oid == InvalidOid)
- elog(ERROR, "network_prefix_quals: no %s operator for type %u",
- opr1name, datatype);
+ if (is_eq)
+ {
+ opr1oid = get_opclass_member(opclass, InvalidOid,
+ BTGreaterEqualStrategyNumber);
+ if (opr1oid == InvalidOid)
+ elog(ERROR, "no >= operator for opclass %u", opclass);
+ }
+ else
+ {
+ opr1oid = get_opclass_member(opclass, InvalidOid,
+ BTGreaterStrategyNumber);
+ if (opr1oid == InvalidOid)
+ elog(ERROR, "no > operator for opclass %u", opclass);
+ }
opr1right = network_scan_first(rightop);
(Expr *) leftop,
(Expr *) makeConst(datatype, -1, opr1right,
false, false));
- result = makeList1(expr);
+ result = list_make1(make_restrictinfo(expr, true, NULL));
/* create clause "key <= network_scan_last( rightop )" */
- opr2oid = find_operator("<=", datatype);
+ opr2oid = get_opclass_member(opclass, InvalidOid,
+ BTLessEqualStrategyNumber);
if (opr2oid == InvalidOid)
- elog(ERROR, "network_prefix_quals: no <= operator for type %u",
- datatype);
+ elog(ERROR, "no <= operator for opclass %u", opclass);
opr2right = network_scan_last(rightop);
(Expr *) leftop,
(Expr *) makeConst(datatype, -1, opr2right,
false, false));
- result = lappend(result, expr);
+ result = lappend(result, make_restrictinfo(expr, true, NULL));
return result;
}
* Handy subroutines for match_special_index_operator() and friends.
*/
-/* See if there is a binary op of the given name for the given datatype */
-/* NB: we assume that only built-in system operators are searched for */
-static Oid
-find_operator(const char *opname, Oid datatype)
-{
- return GetSysCacheOid(OPERNAMENSP,
- PointerGetDatum(opname),
- ObjectIdGetDatum(datatype),
- ObjectIdGetDatum(datatype),
- ObjectIdGetDatum(PG_CATALOG_NAMESPACE));
-}
-
/*
* Generate a Datum of the appropriate type from a C string.
* Note that all of the supported types are pass-by-ref, so the
projects / postgresql / blobdiff