indxpath.c File Reference

#include "postgres.h"
#include <math.h>
#include "access/stratnum.h"
#include "access/sysattr.h"
#include "catalog/pg_am.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_opfamily.h"
#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/pathnode.h"
#include "optimizer/paths.h"
#include "optimizer/predtest.h"
#include "optimizer/prep.h"
#include "optimizer/restrictinfo.h"
#include "optimizer/var.h"
#include "utils/builtins.h"
#include "utils/bytea.h"
#include "utils/lsyscache.h"
#include "utils/pg_locale.h"
#include "utils/selfuncs.h"

Include dependency graph for indxpath.c:

Go to the source code of this file.

Data Structures
struct	IndexClauseSet
struct	PathClauseUsage
struct	ec_member_matches_arg

Macros
#define	IndexCollMatchesExprColl(idxcollation, exprcollation)   ((idxcollation) == InvalidOid || (idxcollation) == (exprcollation))

Enumerations
enum	ScanTypeControl { ST_INDEXSCAN, ST_BITMAPSCAN, ST_ANYSCAN }

Functions
static void	consider_index_join_clauses (PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *rclauseset, IndexClauseSet *jclauseset, IndexClauseSet *eclauseset, List **bitindexpaths)
static void	consider_index_join_outer_rels (PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *rclauseset, IndexClauseSet *jclauseset, IndexClauseSet *eclauseset, List **bitindexpaths, List *indexjoinclauses, int considered_clauses, List **considered_relids)
static void	get_join_index_paths (PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *rclauseset, IndexClauseSet *jclauseset, IndexClauseSet *eclauseset, List **bitindexpaths, Relids relids, List **considered_relids)
static bool	eclass_already_used (EquivalenceClass *parent_ec, Relids oldrelids, List *indexjoinclauses)
static bool	bms_equal_any (Relids relids, List *relids_list)
static void	get_index_paths (PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *clauses, List **bitindexpaths)
static List *	build_index_paths (PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *clauses, bool useful_predicate, ScanTypeControl scantype, bool *skip_nonnative_saop, bool *skip_lower_saop)
static List *	build_paths_for_OR (PlannerInfo *root, RelOptInfo *rel, List *clauses, List *other_clauses)
static List *	generate_bitmap_or_paths (PlannerInfo *root, RelOptInfo *rel, List *clauses, List *other_clauses)
static Path *	choose_bitmap_and (PlannerInfo *root, RelOptInfo *rel, List *paths)
static int	path_usage_comparator (const void *a, const void *b)
static Cost	bitmap_scan_cost_est (PlannerInfo *root, RelOptInfo *rel, Path *ipath)
static Cost	bitmap_and_cost_est (PlannerInfo *root, RelOptInfo *rel, List *paths)
static PathClauseUsage *	classify_index_clause_usage (Path *path, List **clauselist)
static Relids	get_bitmap_tree_required_outer (Path *bitmapqual)
static void	find_indexpath_quals (Path *bitmapqual, List **quals, List **preds)
static int	find_list_position (Node *node, List **nodelist)
static bool	check_index_only (RelOptInfo *rel, IndexOptInfo *index)
static double	get_loop_count (PlannerInfo *root, Index cur_relid, Relids outer_relids)
static double	adjust_rowcount_for_semijoins (PlannerInfo *root, Index cur_relid, Index outer_relid, double rowcount)
static double	approximate_joinrel_size (PlannerInfo *root, Relids relids)
static void	match_restriction_clauses_to_index (RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *clauseset)
static void	match_join_clauses_to_index (PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *clauseset, List **joinorclauses)
static void	match_eclass_clauses_to_index (PlannerInfo *root, IndexOptInfo *index, IndexClauseSet *clauseset)
static void	match_clauses_to_index (IndexOptInfo *index, List *clauses, IndexClauseSet *clauseset)
static void	match_clause_to_index (IndexOptInfo *index, RestrictInfo *rinfo, IndexClauseSet *clauseset)
static bool	match_clause_to_indexcol (IndexOptInfo *index, int indexcol, RestrictInfo *rinfo)
static bool	is_indexable_operator (Oid expr_op, Oid opfamily, bool indexkey_on_left)
static bool	match_rowcompare_to_indexcol (IndexOptInfo *index, int indexcol, Oid opfamily, Oid idxcollation, RowCompareExpr *clause)
static void	match_pathkeys_to_index (IndexOptInfo *index, List *pathkeys, List **orderby_clauses_p, List **clause_columns_p)
static Expr *	match_clause_to_ordering_op (IndexOptInfo *index, int indexcol, Expr *clause, Oid pk_opfamily)
static bool	ec_member_matches_indexcol (PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg)
static bool	match_boolean_index_clause (Node *clause, int indexcol, IndexOptInfo *index)
static bool	match_special_index_operator (Expr *clause, Oid opfamily, Oid idxcollation, bool indexkey_on_left)
static Expr *	expand_boolean_index_clause (Node *clause, int indexcol, IndexOptInfo *index)
static List *	expand_indexqual_opclause (RestrictInfo *rinfo, Oid opfamily, Oid idxcollation)
static RestrictInfo *	expand_indexqual_rowcompare (RestrictInfo *rinfo, IndexOptInfo *index, int indexcol)
static List *	prefix_quals (Node *leftop, Oid opfamily, Oid collation, Const *prefix, Pattern_Prefix_Status pstatus)
static List *	network_prefix_quals (Node *leftop, Oid expr_op, Oid opfamily, Datum rightop)
static Datum	string_to_datum (const char *str, Oid datatype)
static Const *	string_to_const (const char *str, Oid datatype)
void	create_index_paths (PlannerInfo *root, RelOptInfo *rel)
void	check_index_predicates (PlannerInfo *root, RelOptInfo *rel)
bool	relation_has_unique_index_for (PlannerInfo *root, RelOptInfo *rel, List *restrictlist, List *exprlist, List *oprlist)
bool	indexcol_is_bool_constant_for_query (IndexOptInfo *index, int indexcol)
bool	match_index_to_operand (Node *operand, int indexcol, IndexOptInfo *index)
void	expand_indexqual_conditions (IndexOptInfo *index, List *indexclauses, List *indexclausecols, List **indexquals_p, List **indexqualcols_p)
Expr *	adjust_rowcompare_for_index (RowCompareExpr *clause, IndexOptInfo *index, int indexcol, List **indexcolnos, bool *var_on_left_p)

Macro Definition Documentation

IndexCollMatchesExprColl

#define IndexCollMatchesExprColl	(		idxcollation,
			exprcollation
	)		((idxcollation) == InvalidOid || (idxcollation) == (exprcollation))

Definition at line 44 of file indxpath.c.

Referenced by adjust_rowcompare_for_index(), ec_member_matches_indexcol(), match_clause_to_indexcol(), match_clause_to_ordering_op(), and match_rowcompare_to_indexcol().

Enumeration Type Documentation

ScanTypeControl

enum ScanTypeControl

Enumerator
ST_INDEXSCAN
ST_BITMAPSCAN
ST_ANYSCAN

Definition at line 48 of file indxpath.c.

{
    ST_INDEXSCAN,               /* must support amgettuple */
    ST_BITMAPSCAN,              /* must support amgetbitmap */
    ST_ANYSCAN                  /* either is okay */
} ScanTypeControl;

Function Documentation

adjust_rowcompare_for_index()

Expr* adjust_rowcompare_for_index	(	RowCompareExpr *	clause,
		IndexOptInfo *	index,
		int	indexcol,
		List **	indexcolnos,
		bool *	var_on_left_p
	)

Definition at line 3855 of file indxpath.c.

References Assert, bms_is_member(), BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, contain_volatile_functions(), copyObject, elog, ERROR, get_commutator(), get_op_opfamily_properties(), get_op_opfamily_strategy(), get_opfamily_member(), i, IndexOptInfo::indexcollations, IndexCollMatchesExprColl, RowCompareExpr::inputcollids, InvalidOid, lappend_int(), lappend_oid(), RowCompareExpr::largs, lfirst, lfirst_oid, linitial, linitial_oid, list_copy(), list_head(), list_length(), list_make1_int, list_make1_oid, list_truncate(), lnext, make_opclause(), makeNode, match_index_to_operand(), IndexOptInfo::ncolumns, NIL, IndexOptInfo::nkeycolumns, OidIsValid, RowCompareExpr::opfamilies, IndexOptInfo::opfamily, RowCompareExpr::opnos, pull_varnos(), RowCompareExpr::rargs, RowCompareExpr::rctype, IndexOptInfo::rel, RelOptInfo::relid, ROWCOMPARE_GE, and ROWCOMPARE_LE.

Referenced by expand_indexqual_rowcompare(), and fix_indexqual_references().

{
    bool        var_on_left;
    int         op_strategy;
    Oid         op_lefttype;
    Oid         op_righttype;
    int         matching_cols;
    Oid         expr_op;
    List       *opfamilies;
    List       *lefttypes;
    List       *righttypes;
    List       *new_ops;
    ListCell   *largs_cell;
    ListCell   *rargs_cell;
    ListCell   *opnos_cell;
    ListCell   *collids_cell;

    /* We have to figure out (again) how the first col matches */
    var_on_left = match_index_to_operand((Node *) linitial(clause->largs),
                                         indexcol, index);
    Assert(var_on_left ||
           match_index_to_operand((Node *) linitial(clause->rargs),
                                  indexcol, index));
    *var_on_left_p = var_on_left;

    expr_op = linitial_oid(clause->opnos);
    if (!var_on_left)
        expr_op = get_commutator(expr_op);
    get_op_opfamily_properties(expr_op, index->opfamily[indexcol], false,
                               &op_strategy,
                               &op_lefttype,
                               &op_righttype);

    /* Initialize returned list of which index columns are used */
    *indexcolnos = list_make1_int(indexcol);

    /* Build lists of the opfamilies and operator datatypes in case needed */
    opfamilies = list_make1_oid(index->opfamily[indexcol]);
    lefttypes = list_make1_oid(op_lefttype);
    righttypes = list_make1_oid(op_righttype);

    /*
     * See how many of the remaining columns match some index column in the
     * same way.  As in match_clause_to_indexcol(), the "other" side of any
     * potential index condition is OK as long as it doesn't use Vars from the
     * indexed relation.
     */
    matching_cols = 1;
    largs_cell = lnext(list_head(clause->largs));
    rargs_cell = lnext(list_head(clause->rargs));
    opnos_cell = lnext(list_head(clause->opnos));
    collids_cell = lnext(list_head(clause->inputcollids));

    while (largs_cell != NULL)
    {
        Node       *varop;
        Node       *constop;
        int         i;

        expr_op = lfirst_oid(opnos_cell);
        if (var_on_left)
        {
            varop = (Node *) lfirst(largs_cell);
            constop = (Node *) lfirst(rargs_cell);
        }
        else
        {
            varop = (Node *) lfirst(rargs_cell);
            constop = (Node *) lfirst(largs_cell);
            /* indexkey is on right, so commute the operator */
            expr_op = get_commutator(expr_op);
            if (expr_op == InvalidOid)
                break;          /* operator is not usable */
        }
        if (bms_is_member(index->rel->relid, pull_varnos(constop)))
            break;              /* no good, Var on wrong side */
        if (contain_volatile_functions(constop))
            break;              /* no good, volatile comparison value */

        /*
         * The Var side can match any column of the index.
         */
        for (i = 0; i < index->nkeycolumns; i++)
        {
            if (match_index_to_operand(varop, i, index) &&
                get_op_opfamily_strategy(expr_op,
                                         index->opfamily[i]) == op_strategy &&
                IndexCollMatchesExprColl(index->indexcollations[i],
                                         lfirst_oid(collids_cell)))

                break;
        }
        if (i >= index->ncolumns)
            break;              /* no match found */

        /* Add column number to returned list */
        *indexcolnos = lappend_int(*indexcolnos, i);

        /* Add opfamily and datatypes to lists */
        get_op_opfamily_properties(expr_op, index->opfamily[i], false,
                                   &op_strategy,
                                   &op_lefttype,
                                   &op_righttype);
        opfamilies = lappend_oid(opfamilies, index->opfamily[i]);
        lefttypes = lappend_oid(lefttypes, op_lefttype);
        righttypes = lappend_oid(righttypes, op_righttype);

        /* This column matches, keep scanning */
        matching_cols++;
        largs_cell = lnext(largs_cell);
        rargs_cell = lnext(rargs_cell);
        opnos_cell = lnext(opnos_cell);
        collids_cell = lnext(collids_cell);
    }

    /* Return clause as-is if it's all usable as index quals */
    if (matching_cols == list_length(clause->opnos))
        return (Expr *) clause;

    /*
     * We have to generate a subset rowcompare (possibly just one OpExpr). The
     * painful part of this is changing < to <= or > to >=, so deal with that
     * first.
     */
    if (op_strategy == BTLessEqualStrategyNumber ||
        op_strategy == BTGreaterEqualStrategyNumber)
    {
        /* easy, just use the same operators */
        new_ops = list_truncate(list_copy(clause->opnos), matching_cols);
    }
    else
    {
        ListCell   *opfamilies_cell;
        ListCell   *lefttypes_cell;
        ListCell   *righttypes_cell;

        if (op_strategy == BTLessStrategyNumber)
            op_strategy = BTLessEqualStrategyNumber;
        else if (op_strategy == BTGreaterStrategyNumber)
            op_strategy = BTGreaterEqualStrategyNumber;
        else
            elog(ERROR, "unexpected strategy number %d", op_strategy);
        new_ops = NIL;
        lefttypes_cell = list_head(lefttypes);
        righttypes_cell = list_head(righttypes);
        foreach(opfamilies_cell, opfamilies)
        {
            Oid         opfam = lfirst_oid(opfamilies_cell);
            Oid         lefttype = lfirst_oid(lefttypes_cell);
            Oid         righttype = lfirst_oid(righttypes_cell);

            expr_op = get_opfamily_member(opfam, lefttype, righttype,
                                          op_strategy);
            if (!OidIsValid(expr_op))   /* should not happen */
                elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
                     op_strategy, lefttype, righttype, opfam);
            if (!var_on_left)
            {
                expr_op = get_commutator(expr_op);
                if (!OidIsValid(expr_op))   /* should not happen */
                    elog(ERROR, "could not find commutator of operator %d(%u,%u) of opfamily %u",
                         op_strategy, lefttype, righttype, opfam);
            }
            new_ops = lappend_oid(new_ops, expr_op);
            lefttypes_cell = lnext(lefttypes_cell);
            righttypes_cell = lnext(righttypes_cell);
        }
    }

    /* If we have more than one matching col, create a subset rowcompare */
    if (matching_cols > 1)
    {
        RowCompareExpr *rc = makeNode(RowCompareExpr);

        if (var_on_left)
            rc->rctype = (RowCompareType) op_strategy;
        else
            rc->rctype = (op_strategy == BTLessEqualStrategyNumber) ?
                ROWCOMPARE_GE : ROWCOMPARE_LE;
        rc->opnos = new_ops;
        rc->opfamilies = list_truncate(list_copy(clause->opfamilies),
                                       matching_cols);
        rc->inputcollids = list_truncate(list_copy(clause->inputcollids),
                                         matching_cols);
        rc->largs = list_truncate(copyObject(clause->largs),
                                  matching_cols);
        rc->rargs = list_truncate(copyObject(clause->rargs),
                                  matching_cols);
        return (Expr *) rc;
    }
    else
    {
        return make_opclause(linitial_oid(new_ops), BOOLOID, false,
                             copyObject(linitial(clause->largs)),
                             copyObject(linitial(clause->rargs)),
                             InvalidOid,
                             linitial_oid(clause->inputcollids));
    }
}

adjust_rowcount_for_semijoins()

static double adjust_rowcount_for_semijoins ( PlannerInfo *  root, Index  cur_relid, Index  outer_relid, double  rowcount  )

static

Definition at line 2027 of file indxpath.c.

References approximate_joinrel_size(), bms_is_member(), estimate_num_groups(), PlannerInfo::join_info_list, JOIN_SEMI, SpecialJoinInfo::jointype, lfirst, SpecialJoinInfo::semi_rhs_exprs, SpecialJoinInfo::syn_lefthand, and SpecialJoinInfo::syn_righthand.

Referenced by get_loop_count().

{
    ListCell   *lc;

    foreach(lc, root->join_info_list)
    {
        SpecialJoinInfo *sjinfo = (SpecialJoinInfo *) lfirst(lc);

        if (sjinfo->jointype == JOIN_SEMI &&
            bms_is_member(cur_relid, sjinfo->syn_lefthand) &&
            bms_is_member(outer_relid, sjinfo->syn_righthand))
        {
            /* Estimate number of unique-ified rows */
            double      nraw;
            double      nunique;

            nraw = approximate_joinrel_size(root, sjinfo->syn_righthand);
            nunique = estimate_num_groups(root,
                                          sjinfo->semi_rhs_exprs,
                                          nraw,
                                          NULL);
            if (rowcount > nunique)
                rowcount = nunique;
        }
    }
    return rowcount;
}

approximate_joinrel_size()

static double approximate_joinrel_size ( PlannerInfo *  root, Relids  relids  )

static

Definition at line 2070 of file indxpath.c.

References Assert, bms_next_member(), IS_DUMMY_REL, RelOptInfo::relid, RelOptInfo::rows, PlannerInfo::simple_rel_array, and PlannerInfo::simple_rel_array_size.

Referenced by adjust_rowcount_for_semijoins().

{
    double      rowcount = 1.0;
    int         relid;

    relid = -1;
    while ((relid = bms_next_member(relids, relid)) >= 0)
    {
        RelOptInfo *rel;

        /* Paranoia: ignore bogus relid indexes */
        if (relid >= root->simple_rel_array_size)
            continue;
        rel = root->simple_rel_array[relid];
        if (rel == NULL)
            continue;
        Assert(rel->relid == relid);    /* sanity check on array */

        /* Relation could be proven empty, if so ignore */
        if (IS_DUMMY_REL(rel))
            continue;

        /* Otherwise, rel's rows estimate should be valid by now */
        Assert(rel->rows > 0);

        /* Accumulate product */
        rowcount *= rel->rows;
    }
    return rowcount;
}

bitmap_and_cost_est()

static Cost bitmap_and_cost_est ( PlannerInfo *  root, RelOptInfo *  rel, List *  paths  )

static

Definition at line 1640 of file indxpath.c.

References BitmapHeapPath::bitmapqual, BitmapAndPath::bitmapquals, cost_bitmap_and_node(), cost_bitmap_heap_scan(), get_baserel_parampathinfo(), get_bitmap_tree_required_outer(), get_loop_count(), NIL, Path::parallel_workers, Path::param_info, Path::parent, BitmapHeapPath::path, BitmapAndPath::path, Path::pathkeys, Path::pathtarget, Path::pathtype, RelOptInfo::relid, RelOptInfo::reltarget, T_BitmapAnd, T_BitmapAndPath, T_BitmapHeapPath, T_BitmapHeapScan, Path::total_cost, and Path::type.

Referenced by choose_bitmap_and().

{
    BitmapAndPath apath;
    BitmapHeapPath bpath;
    Relids      required_outer;

    /* Set up a dummy BitmapAndPath */
    apath.path.type = T_BitmapAndPath;
    apath.path.pathtype = T_BitmapAnd;
    apath.path.parent = rel;
    apath.path.pathtarget = rel->reltarget;
    apath.path.param_info = NULL;   /* not used in bitmap trees */
    apath.path.pathkeys = NIL;
    apath.bitmapquals = paths;
    cost_bitmap_and_node(&apath, root);

    /* Identify required outer rels, in case it's a parameterized scan */
    required_outer = get_bitmap_tree_required_outer((Path *) &apath);

    /* Set up a dummy BitmapHeapPath */
    bpath.path.type = T_BitmapHeapPath;
    bpath.path.pathtype = T_BitmapHeapScan;
    bpath.path.parent = rel;
    bpath.path.pathtarget = rel->reltarget;
    bpath.path.param_info = get_baserel_parampathinfo(root, rel,
                                                      required_outer);
    bpath.path.pathkeys = NIL;
    bpath.bitmapqual = (Path *) &apath;

    /*
     * Check the cost of temporary path without considering parallelism.
     * Parallel bitmap heap path will be considered at later stage.
     */
    bpath.path.parallel_workers = 0;

    /* Now we can do cost_bitmap_heap_scan */
    cost_bitmap_heap_scan(&bpath.path, root, rel,
                          bpath.path.param_info,
                          (Path *) &apath,
                          get_loop_count(root, rel->relid, required_outer));

    return bpath.path.total_cost;
}

bitmap_scan_cost_est()

static Cost bitmap_scan_cost_est ( PlannerInfo *  root, RelOptInfo *  rel, Path *  ipath  )

static

Definition at line 1604 of file indxpath.c.

References BitmapHeapPath::bitmapqual, cost_bitmap_heap_scan(), get_baserel_parampathinfo(), get_bitmap_tree_required_outer(), get_loop_count(), NIL, Path::parallel_workers, Path::param_info, Path::parent, BitmapHeapPath::path, Path::pathkeys, Path::pathtarget, Path::pathtype, RelOptInfo::relid, RelOptInfo::reltarget, T_BitmapHeapPath, T_BitmapHeapScan, Path::total_cost, and Path::type.

Referenced by choose_bitmap_and().

{
    BitmapHeapPath bpath;
    Relids      required_outer;

    /* Identify required outer rels, in case it's a parameterized scan */
    required_outer = get_bitmap_tree_required_outer(ipath);

    /* Set up a dummy BitmapHeapPath */
    bpath.path.type = T_BitmapHeapPath;
    bpath.path.pathtype = T_BitmapHeapScan;
    bpath.path.parent = rel;
    bpath.path.pathtarget = rel->reltarget;
    bpath.path.param_info = get_baserel_parampathinfo(root, rel,
                                                      required_outer);
    bpath.path.pathkeys = NIL;
    bpath.bitmapqual = ipath;

    /*
     * Check the cost of temporary path without considering parallelism.
     * Parallel bitmap heap path will be considered at later stage.
     */
    bpath.path.parallel_workers = 0;
    cost_bitmap_heap_scan(&bpath.path, root, rel,
                          bpath.path.param_info,
                          ipath,
                          get_loop_count(root, rel->relid, required_outer));

    return bpath.path.total_cost;
}

bms_equal_any()

static bool bms_equal_any ( Relids  relids, List *  relids_list  )

static

Definition at line 706 of file indxpath.c.

References bms_equal(), and lfirst.

Referenced by consider_index_join_outer_rels(), create_index_paths(), and get_join_index_paths().

{
    ListCell   *lc;

    foreach(lc, relids_list)
    {
        if (bms_equal(relids, (Relids) lfirst(lc)))
            return true;
    }
    return false;
}

build_index_paths()

static List * build_index_paths ( PlannerInfo *  root, RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  clauses, bool  useful_predicate, ScanTypeControl  scantype, bool *  skip_nonnative_saop, bool *  skip_lower_saop  )

static

Definition at line 857 of file indxpath.c.

References add_partial_path(), IndexOptInfo::amcanorderbyop, IndexOptInfo::amcanparallel, IndexOptInfo::amhasgetbitmap, IndexOptInfo::amhasgettuple, IndexOptInfo::amoptionalkey, IndexOptInfo::amsearcharray, Assert, BackwardScanDirection, bms_add_members(), bms_copy(), bms_del_member(), bms_is_empty(), build_index_pathkeys(), check_index_only(), RestrictInfo::clause, RestrictInfo::clause_relids, RelOptInfo::consider_parallel, create_index_path(), ForwardScanDirection, get_loop_count(), has_useful_pathkeys(), IndexClauseSet::indexclauses, IsA, lappend(), lappend_int(), RelOptInfo::lateral_relids, lfirst, match_pathkeys_to_index(), IndexOptInfo::ncolumns, NIL, NoMovementScanDirection, Path::parallel_workers, IndexPath::path, pfree(), PlannerInfo::query_pathkeys, RelOptInfo::relid, IndexOptInfo::sortopfamily, ST_ANYSCAN, ST_BITMAPSCAN, ST_INDEXSCAN, and truncate_useless_pathkeys().

Referenced by build_paths_for_OR(), and get_index_paths().

{
    List       *result = NIL;
    IndexPath  *ipath;
    List       *index_clauses;
    List       *clause_columns;
    Relids      outer_relids;
    double      loop_count;
    List       *orderbyclauses;
    List       *orderbyclausecols;
    List       *index_pathkeys;
    List       *useful_pathkeys;
    bool        found_lower_saop_clause;
    bool        pathkeys_possibly_useful;
    bool        index_is_ordered;
    bool        index_only_scan;
    int         indexcol;

    /*
     * Check that index supports the desired scan type(s)
     */
    switch (scantype)
    {
        case ST_INDEXSCAN:
            if (!index->amhasgettuple)
                return NIL;
            break;
        case ST_BITMAPSCAN:
            if (!index->amhasgetbitmap)
                return NIL;
            break;
        case ST_ANYSCAN:
            /* either or both are OK */
            break;
    }

    /*
     * 1. Collect the index clauses into a single list.
     *
     * We build a list of RestrictInfo nodes for clauses to be used with this
     * index, along with an integer list of the index column numbers (zero
     * based) that each clause should be used with.  The clauses are ordered
     * by index key, so that the column numbers form a nondecreasing sequence.
     * (This order is depended on by btree and possibly other places.)  The
     * lists can be empty, if the index AM allows that.
     *
     * found_lower_saop_clause is set true if we accept a ScalarArrayOpExpr
     * index clause for a non-first index column.  This prevents us from
     * assuming that the scan result is ordered.  (Actually, the result is
     * still ordered if there are equality constraints for all earlier
     * columns, but it seems too expensive and non-modular for this code to be
     * aware of that refinement.)
     *
     * We also build a Relids set showing which outer rels are required by the
     * selected clauses.  Any lateral_relids are included in that, but not
     * otherwise accounted for.
     */
    index_clauses = NIL;
    clause_columns = NIL;
    found_lower_saop_clause = false;
    outer_relids = bms_copy(rel->lateral_relids);
    for (indexcol = 0; indexcol < index->ncolumns; indexcol++)
    {
        ListCell   *lc;

        foreach(lc, clauses->indexclauses[indexcol])
        {
            RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

            if (IsA(rinfo->clause, ScalarArrayOpExpr))
            {
                if (!index->amsearcharray)
                {
                    if (skip_nonnative_saop)
                    {
                        /* Ignore because not supported by index */
                        *skip_nonnative_saop = true;
                        continue;
                    }
                    /* Caller had better intend this only for bitmap scan */
                    Assert(scantype == ST_BITMAPSCAN);
                }
                if (indexcol > 0)
                {
                    if (skip_lower_saop)
                    {
                        /* Caller doesn't want to lose index ordering */
                        *skip_lower_saop = true;
                        continue;
                    }
                    found_lower_saop_clause = true;
                }
            }
            index_clauses = lappend(index_clauses, rinfo);
            clause_columns = lappend_int(clause_columns, indexcol);
            outer_relids = bms_add_members(outer_relids,
                                           rinfo->clause_relids);
        }

        /*
         * If no clauses match the first index column, check for amoptionalkey
         * restriction.  We can't generate a scan over an index with
         * amoptionalkey = false unless there's at least one index clause.
         * (When working on columns after the first, this test cannot fail. It
         * is always okay for columns after the first to not have any
         * clauses.)
         */
        if (index_clauses == NIL && !index->amoptionalkey)
            return NIL;
    }

    /* We do not want the index's rel itself listed in outer_relids */
    outer_relids = bms_del_member(outer_relids, rel->relid);
    /* Enforce convention that outer_relids is exactly NULL if empty */
    if (bms_is_empty(outer_relids))
        outer_relids = NULL;

    /* Compute loop_count for cost estimation purposes */
    loop_count = get_loop_count(root, rel->relid, outer_relids);

    /*
     * 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
     * if we are only trying to build bitmap indexscans, nor if we have to
     * assume the scan is unordered.
     */
    pathkeys_possibly_useful = (scantype != ST_BITMAPSCAN &&
                                !found_lower_saop_clause &&
                                has_useful_pathkeys(root, rel));
    index_is_ordered = (index->sortopfamily != NULL);
    if (index_is_ordered && pathkeys_possibly_useful)
    {
        index_pathkeys = build_index_pathkeys(root, index,
                                              ForwardScanDirection);
        useful_pathkeys = truncate_useless_pathkeys(root, rel,
                                                    index_pathkeys);
        orderbyclauses = NIL;
        orderbyclausecols = NIL;
    }
    else if (index->amcanorderbyop && pathkeys_possibly_useful)
    {
        /* see if we can generate ordering operators for query_pathkeys */
        match_pathkeys_to_index(index, root->query_pathkeys,
                                &orderbyclauses,
                                &orderbyclausecols);
        if (orderbyclauses)
            useful_pathkeys = root->query_pathkeys;
        else
            useful_pathkeys = NIL;
    }
    else
    {
        useful_pathkeys = NIL;
        orderbyclauses = NIL;
        orderbyclausecols = NIL;
    }

    /*
     * 3. Check if an index-only scan is possible.  If we're not building
     * plain indexscans, this isn't relevant since bitmap scans don't support
     * index data retrieval anyway.
     */
    index_only_scan = (scantype != ST_BITMAPSCAN &&
                       check_index_only(rel, index));

    /*
     * 4. 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 useful
     * predicate, OR an index-only scan is possible.
     */
    if (index_clauses != NIL || useful_pathkeys != NIL || useful_predicate ||
        index_only_scan)
    {
        ipath = create_index_path(root, index,
                                  index_clauses,
                                  clause_columns,
                                  orderbyclauses,
                                  orderbyclausecols,
                                  useful_pathkeys,
                                  index_is_ordered ?
                                  ForwardScanDirection :
                                  NoMovementScanDirection,
                                  index_only_scan,
                                  outer_relids,
                                  loop_count,
                                  false);
        result = lappend(result, ipath);

        /*
         * If appropriate, consider parallel index scan.  We don't allow
         * parallel index scan for bitmap index scans.
         */
        if (index->amcanparallel &&
            rel->consider_parallel && outer_relids == NULL &&
            scantype != ST_BITMAPSCAN)
        {
            ipath = create_index_path(root, index,
                                      index_clauses,
                                      clause_columns,
                                      orderbyclauses,
                                      orderbyclausecols,
                                      useful_pathkeys,
                                      index_is_ordered ?
                                      ForwardScanDirection :
                                      NoMovementScanDirection,
                                      index_only_scan,
                                      outer_relids,
                                      loop_count,
                                      true);

            /*
             * if, after costing the path, we find that it's not worth using
             * parallel workers, just free it.
             */
            if (ipath->path.parallel_workers > 0)
                add_partial_path(rel, (Path *) ipath);
            else
                pfree(ipath);
        }
    }

    /*
     * 5. If the index is ordered, a backwards scan might be interesting.
     */
    if (index_is_ordered && pathkeys_possibly_useful)
    {
        index_pathkeys = build_index_pathkeys(root, index,
                                              BackwardScanDirection);
        useful_pathkeys = truncate_useless_pathkeys(root, rel,
                                                    index_pathkeys);
        if (useful_pathkeys != NIL)
        {
            ipath = create_index_path(root, index,
                                      index_clauses,
                                      clause_columns,
                                      NIL,
                                      NIL,
                                      useful_pathkeys,
                                      BackwardScanDirection,
                                      index_only_scan,
                                      outer_relids,
                                      loop_count,
                                      false);
            result = lappend(result, ipath);

            /* If appropriate, consider parallel index scan */
            if (index->amcanparallel &&
                rel->consider_parallel && outer_relids == NULL &&
                scantype != ST_BITMAPSCAN)
            {
                ipath = create_index_path(root, index,
                                          index_clauses,
                                          clause_columns,
                                          NIL,
                                          NIL,
                                          useful_pathkeys,
                                          BackwardScanDirection,
                                          index_only_scan,
                                          outer_relids,
                                          loop_count,
                                          true);

                /*
                 * if, after costing the path, we find that it's not worth
                 * using parallel workers, just free it.
                 */
                if (ipath->path.parallel_workers > 0)
                    add_partial_path(rel, (Path *) ipath);
                else
                    pfree(ipath);
            }
        }
    }

    return result;
}

build_paths_for_OR()

static List * build_paths_for_OR ( PlannerInfo *  root, RelOptInfo *  rel, List *  clauses, List *  other_clauses  )

static

Definition at line 1167 of file indxpath.c.

References IndexOptInfo::amhasgetbitmap, build_index_paths(), RelOptInfo::indexlist, IndexOptInfo::indpred, lfirst, list_concat(), list_copy(), match_clauses_to_index(), MemSet, NIL, IndexClauseSet::nonempty, predicate_implied_by(), IndexOptInfo::predOK, and ST_BITMAPSCAN.

Referenced by generate_bitmap_or_paths().

{
    List       *result = NIL;
    List       *all_clauses = NIL;  /* not computed till needed */
    ListCell   *lc;

    foreach(lc, rel->indexlist)
    {
        IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);
        IndexClauseSet clauseset;
        List       *indexpaths;
        bool        useful_predicate;

        /* Ignore index if it doesn't support bitmap scans */
        if (!index->amhasgetbitmap)
            continue;

        /*
         * Ignore partial indexes that do not match the query.  If a partial
         * index is marked predOK then we know it's OK.  Otherwise, we have to
         * test whether the added clauses are sufficient to imply the
         * predicate. If so, we can 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 (index->predOK)
            {
                /* Usable, but don't set useful_predicate */
            }
            else
            {
                /* Form all_clauses if not done already */
                if (all_clauses == NIL)
                    all_clauses = list_concat(list_copy(clauses),
                                              other_clauses);

                if (!predicate_implied_by(index->indpred, all_clauses, false))
                    continue;   /* can't use it at all */

                if (!predicate_implied_by(index->indpred, other_clauses, false))
                    useful_predicate = true;
            }
        }

        /*
         * Identify the restriction clauses that can match the index.
         */
        MemSet(&clauseset, 0, sizeof(clauseset));
        match_clauses_to_index(index, clauses, &clauseset);

        /*
         * If no matches so far, and the index predicate isn't useful, we
         * don't want it.
         */
        if (!clauseset.nonempty && !useful_predicate)
            continue;

        /*
         * Add "other" restriction clauses to the clauseset.
         */
        match_clauses_to_index(index, other_clauses, &clauseset);

        /*
         * Construct paths if possible.
         */
        indexpaths = build_index_paths(root, rel,
                                       index, &clauseset,
                                       useful_predicate,
                                       ST_BITMAPSCAN,
                                       NULL,
                                       NULL);
        result = list_concat(result, indexpaths);
    }

    return result;
}

check_index_only()

static bool check_index_only ( RelOptInfo *  rel, IndexOptInfo *  index  )

static

Definition at line 1862 of file indxpath.c.

References bms_add_member(), bms_del_members(), bms_free(), bms_is_subset(), IndexOptInfo::canreturn, RestrictInfo::clause, enable_indexonlyscan, PathTarget::exprs, FirstLowInvalidHeapAttributeNumber, i, IndexOptInfo::indexkeys, IndexOptInfo::indrestrictinfo, lfirst, IndexOptInfo::ncolumns, pull_varattnos(), RelOptInfo::relid, and RelOptInfo::reltarget.

Referenced by build_index_paths().

{
    bool        result;
    Bitmapset  *attrs_used = NULL;
    Bitmapset  *index_canreturn_attrs = NULL;
    Bitmapset  *index_cannotreturn_attrs = NULL;
    ListCell   *lc;
    int         i;

    /* Index-only scans must be enabled */
    if (!enable_indexonlyscan)
        return false;

    /*
     * Check that all needed attributes of the relation are available from the
     * index.
     */

    /*
     * First, identify all the attributes needed for joins or final output.
     * Note: we must look at rel's targetlist, not the attr_needed data,
     * because attr_needed isn't computed for inheritance child rels.
     */
    pull_varattnos((Node *) rel->reltarget->exprs, rel->relid, &attrs_used);

    /*
     * Add all the attributes used by restriction clauses; but consider only
     * those clauses not implied by the index predicate, since ones that are
     * so implied don't need to be checked explicitly in the plan.
     *
     * Note: attributes used only in index quals would not be needed at
     * runtime either, if we are certain that the index is not lossy.  However
     * it'd be complicated to account for that accurately, and it doesn't
     * matter in most cases, since we'd conclude that such attributes are
     * available from the index anyway.
     */
    foreach(lc, index->indrestrictinfo)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

        pull_varattnos((Node *) rinfo->clause, rel->relid, &attrs_used);
    }

    /*
     * Construct a bitmapset of columns that the index can return back in an
     * index-only scan.  If there are multiple index columns containing the
     * same attribute, all of them must be capable of returning the value,
     * since we might recheck operators on any of them.  (Potentially we could
     * be smarter about that, but it's such a weird situation that it doesn't
     * seem worth spending a lot of sweat on.)
     */
    for (i = 0; i < index->ncolumns; i++)
    {
        int         attno = index->indexkeys[i];

        /*
         * For the moment, we just ignore index expressions.  It might be nice
         * to do something with them, later.
         */
        if (attno == 0)
            continue;

        if (index->canreturn[i])
            index_canreturn_attrs =
                bms_add_member(index_canreturn_attrs,
                               attno - FirstLowInvalidHeapAttributeNumber);
        else
            index_cannotreturn_attrs =
                bms_add_member(index_cannotreturn_attrs,
                               attno - FirstLowInvalidHeapAttributeNumber);
    }

    index_canreturn_attrs = bms_del_members(index_canreturn_attrs,
                                            index_cannotreturn_attrs);

    /* Do we have all the necessary attributes? */
    result = bms_is_subset(attrs_used, index_canreturn_attrs);

    bms_free(attrs_used);
    bms_free(index_canreturn_attrs);
    bms_free(index_cannotreturn_attrs);

    return result;
}

check_index_predicates()

void check_index_predicates	(	PlannerInfo *	root,
		RelOptInfo *	rel
	)

Definition at line 2795 of file indxpath.c.

References PlannerInfo::all_baserels, Assert, RelOptInfo::baserestrictinfo, bms_difference(), bms_is_empty(), bms_union(), RestrictInfo::clause, contain_mutable_functions(), find_childrel_parents(), generate_join_implied_equalities(), get_plan_rowmark(), RelOptInfo::indexlist, IndexOptInfo::indpred, IndexOptInfo::indrestrictinfo, IS_SIMPLE_REL, join_clause_is_movable_to(), RelOptInfo::joininfo, lappend(), lfirst, list_concat(), list_copy(), list_make1, NIL, PlannerInfo::parse, predicate_implied_by(), IndexOptInfo::predOK, RelOptInfo::relid, RelOptInfo::relids, RELOPT_OTHER_MEMBER_REL, RelOptInfo::reloptkind, Query::resultRelation, and PlannerInfo::rowMarks.

Referenced by set_plain_rel_size(), and set_tablesample_rel_size().

{
    List       *clauselist;
    bool        have_partial;
    bool        is_target_rel;
    Relids      otherrels;
    ListCell   *lc;

    /* Indexes are available only on base or "other" member relations. */
    Assert(IS_SIMPLE_REL(rel));

    /*
     * Initialize the indrestrictinfo lists to be identical to
     * baserestrictinfo, and check whether there are any partial indexes.  If
     * not, this is all we need to do.
     */
    have_partial = false;
    foreach(lc, rel->indexlist)
    {
        IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);

        index->indrestrictinfo = rel->baserestrictinfo;
        if (index->indpred)
            have_partial = true;
    }
    if (!have_partial)
        return;

    /*
     * Construct a list of clauses that we can assume true for the purpose of
     * proving the index(es) usable.  Restriction clauses for the rel are
     * always usable, and so are any join clauses that are "movable to" this
     * rel.  Also, we can consider any EC-derivable join clauses (which must
     * be "movable to" this rel, by definition).
     */
    clauselist = list_copy(rel->baserestrictinfo);

    /* Scan the rel's join clauses */
    foreach(lc, rel->joininfo)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

        /* Check if clause can be moved to this rel */
        if (!join_clause_is_movable_to(rinfo, rel))
            continue;

        clauselist = lappend(clauselist, rinfo);
    }

    /*
     * Add on any equivalence-derivable join clauses.  Computing the correct
     * relid sets for generate_join_implied_equalities is slightly tricky
     * because the rel could be a child rel rather than a true baserel, and in
     * that case we must remove its parents' relid(s) from all_baserels.
     */
    if (rel->reloptkind == RELOPT_OTHER_MEMBER_REL)
        otherrels = bms_difference(root->all_baserels,
                                   find_childrel_parents(root, rel));
    else
        otherrels = bms_difference(root->all_baserels, rel->relids);

    if (!bms_is_empty(otherrels))
        clauselist =
            list_concat(clauselist,
                        generate_join_implied_equalities(root,
                                                         bms_union(rel->relids,
                                                                   otherrels),
                                                         otherrels,
                                                         rel));

    /*
     * Normally we remove quals that are implied by a partial index's
     * predicate from indrestrictinfo, indicating that they need not be
     * checked explicitly by an indexscan plan using this index.  However, if
     * the rel is a target relation of UPDATE/DELETE/SELECT FOR UPDATE, we
     * cannot remove such quals from the plan, because they need to be in the
     * plan so that they will be properly rechecked by EvalPlanQual testing.
     * Some day we might want to remove such quals from the main plan anyway
     * and pass them through to EvalPlanQual via a side channel; but for now,
     * we just don't remove implied quals at all for target relations.
     */
    is_target_rel = (rel->relid == root->parse->resultRelation ||
                     get_plan_rowmark(root->rowMarks, rel->relid) != NULL);

    /*
     * Now try to prove each index predicate true, and compute the
     * indrestrictinfo lists for partial indexes.  Note that we compute the
     * indrestrictinfo list even for non-predOK indexes; this might seem
     * wasteful, but we may be able to use such indexes in OR clauses, cf
     * generate_bitmap_or_paths().
     */
    foreach(lc, rel->indexlist)
    {
        IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);
        ListCell   *lcr;

        if (index->indpred == NIL)
            continue;           /* ignore non-partial indexes here */

        if (!index->predOK)     /* don't repeat work if already proven OK */
            index->predOK = predicate_implied_by(index->indpred, clauselist,
                                                 false);

        /* If rel is an update target, leave indrestrictinfo as set above */
        if (is_target_rel)
            continue;

        /* Else compute indrestrictinfo as the non-implied quals */
        index->indrestrictinfo = NIL;
        foreach(lcr, rel->baserestrictinfo)
        {
            RestrictInfo *rinfo = (RestrictInfo *) lfirst(lcr);

            /* predicate_implied_by() assumes first arg is immutable */
            if (contain_mutable_functions((Node *) rinfo->clause) ||
                !predicate_implied_by(list_make1(rinfo->clause),
                                      index->indpred, false))
                index->indrestrictinfo = lappend(index->indrestrictinfo, rinfo);
        }
    }
}

choose_bitmap_and()

static Path * choose_bitmap_and ( PlannerInfo *  root, RelOptInfo *  rel, List *  paths  )

static

Definition at line 1370 of file indxpath.c.

References Assert, bitmap_and_cost_est(), bitmap_scan_cost_est(), bms_add_members(), bms_copy(), bms_equal(), bms_overlap(), classify_index_clause_usage(), PathClauseUsage::clauseids, cost_bitmap_tree_node(), create_bitmap_and_path(), i, lappend(), lfirst, linitial, list_concat(), list_copy(), list_delete_cell(), list_free(), list_head(), list_length(), list_make1, lnext, NIL, palloc(), PathClauseUsage::path, path_usage_comparator(), predicate_implied_by(), PathClauseUsage::preds, qsort, and PathClauseUsage::quals.

Referenced by create_index_paths(), and generate_bitmap_or_paths().

{
    int         npaths = list_length(paths);
    PathClauseUsage **pathinfoarray;
    PathClauseUsage *pathinfo;
    List       *clauselist;
    List       *bestpaths = NIL;
    Cost        bestcost = 0;
    int         i,
                j;
    ListCell   *l;

    Assert(npaths > 0);         /* else caller error */
    if (npaths == 1)
        return (Path *) linitial(paths);    /* easy case */

    /*
     * 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.  Moreover, it's completely impractical if there are a large
     * number of paths, since the work would grow as O(2^N).
     *
     * As a heuristic, we first check for paths using exactly the same sets of
     * WHERE clauses + index predicate conditions, and reject all but the
     * cheapest-to-scan in any such group.  This primarily gets rid of indexes
     * that include the interesting columns but also irrelevant columns.  (In
     * situations where the DBA has gone overboard on creating variant
     * indexes, this can make for a very large reduction in the number of
     * paths considered further.)
     *
     * We then sort the surviving paths with the cheapest-to-scan first, and
     * for each path, consider using that path alone as the basis for a bitmap
     * scan.  Then we consider bitmap AND scans formed from that path plus
     * each subsequent (higher-cost) path, adding on a subsequent path if it
     * results in a reduction in the estimated total scan cost. This means we
     * consider about O(N^2) rather than O(2^N) path combinations, which is
     * quite tolerable, especially given than N is usually reasonably small
     * because of the prefiltering step.  The cheapest of these is returned.
     *
     * We will only consider AND combinations in which no two indexes use the
     * same WHERE clause.  This is a bit of a kluge: it's needed because
     * costsize.c and clausesel.c aren't very smart about redundant clauses.
     * They will usually double-count the redundant clauses, producing a
     * too-small selectivity that makes a redundant AND step look like it
     * reduces the total cost.  Perhaps someday that code will be smarter and
     * we can remove this limitation.  (But note that this also defends
     * against flat-out duplicate input paths, which can happen because
     * match_join_clauses_to_index will find the same OR join clauses that
     * extract_restriction_or_clauses has pulled OR restriction clauses out
     * of.)
     *
     * For the same reason, we reject AND combinations in which an index
     * predicate clause duplicates another clause.  Here we find it necessary
     * to be even stricter: we'll reject a partial index if any of its
     * predicate clauses are implied by the set of WHERE clauses and predicate
     * clauses used so far.  This covers cases such as a condition "x = 42"
     * used with a plain index, followed by a clauseless scan of a partial
     * index "WHERE x >= 40 AND x < 50".  The partial index has been accepted
     * only because "x = 42" was present, and so allowing it would partially
     * double-count selectivity.  (We could use predicate_implied_by on
     * regular qual clauses too, to have a more intelligent, but much more
     * expensive, check for redundancy --- but in most cases simple equality
     * seems to suffice.)
     */

    /*
     * Extract clause usage info and detect any paths that use exactly the
     * same set of clauses; keep only the cheapest-to-scan of any such groups.
     * The surviving paths are put into an array for qsort'ing.
     */
    pathinfoarray = (PathClauseUsage **)
        palloc(npaths * sizeof(PathClauseUsage *));
    clauselist = NIL;
    npaths = 0;
    foreach(l, paths)
    {
        Path       *ipath = (Path *) lfirst(l);

        pathinfo = classify_index_clause_usage(ipath, &clauselist);
        for (i = 0; i < npaths; i++)
        {
            if (bms_equal(pathinfo->clauseids, pathinfoarray[i]->clauseids))
                break;
        }
        if (i < npaths)
        {
            /* duplicate clauseids, keep the cheaper one */
            Cost        ncost;
            Cost        ocost;
            Selectivity nselec;
            Selectivity oselec;

            cost_bitmap_tree_node(pathinfo->path, &ncost, &nselec);
            cost_bitmap_tree_node(pathinfoarray[i]->path, &ocost, &oselec);
            if (ncost < ocost)
                pathinfoarray[i] = pathinfo;
        }
        else
        {
            /* not duplicate clauseids, add to array */
            pathinfoarray[npaths++] = pathinfo;
        }
    }

    /* If only one surviving path, we're done */
    if (npaths == 1)
        return pathinfoarray[0]->path;

    /* Sort the surviving paths by index access cost */
    qsort(pathinfoarray, npaths, sizeof(PathClauseUsage *),
          path_usage_comparator);

    /*
     * For each surviving index, consider it as an "AND group leader", and see
     * whether adding on any of the later indexes results in an AND path with
     * cheaper total cost than before.  Then take the cheapest AND group.
     */
    for (i = 0; i < npaths; i++)
    {
        Cost        costsofar;
        List       *qualsofar;
        Bitmapset  *clauseidsofar;
        ListCell   *lastcell;

        pathinfo = pathinfoarray[i];
        paths = list_make1(pathinfo->path);
        costsofar = bitmap_scan_cost_est(root, rel, pathinfo->path);
        qualsofar = list_concat(list_copy(pathinfo->quals),
                                list_copy(pathinfo->preds));
        clauseidsofar = bms_copy(pathinfo->clauseids);
        lastcell = list_head(paths);    /* for quick deletions */

        for (j = i + 1; j < npaths; j++)
        {
            Cost        newcost;

            pathinfo = pathinfoarray[j];
            /* Check for redundancy */
            if (bms_overlap(pathinfo->clauseids, clauseidsofar))
                continue;       /* consider it redundant */
            if (pathinfo->preds)
            {
                bool        redundant = false;

                /* we check each predicate clause separately */
                foreach(l, pathinfo->preds)
                {
                    Node       *np = (Node *) lfirst(l);

                    if (predicate_implied_by(list_make1(np), qualsofar, false))
                    {
                        redundant = true;
                        break;  /* out of inner foreach loop */
                    }
                }
                if (redundant)
                    continue;
            }
            /* tentatively add new path to paths, so we can estimate cost */
            paths = lappend(paths, pathinfo->path);
            newcost = bitmap_and_cost_est(root, rel, paths);
            if (newcost < costsofar)
            {
                /* keep new path in paths, update subsidiary variables */
                costsofar = newcost;
                qualsofar = list_concat(qualsofar,
                                        list_copy(pathinfo->quals));
                qualsofar = list_concat(qualsofar,
                                        list_copy(pathinfo->preds));
                clauseidsofar = bms_add_members(clauseidsofar,
                                                pathinfo->clauseids);
                lastcell = lnext(lastcell);
            }
            else
            {
                /* reject new path, remove it from paths list */
                paths = list_delete_cell(paths, lnext(lastcell), lastcell);
            }
            Assert(lnext(lastcell) == NULL);
        }

        /* Keep the cheapest AND-group (or singleton) */
        if (i == 0 || costsofar < bestcost)
        {
            bestpaths = paths;
            bestcost = costsofar;
        }

        /* some easy cleanup (we don't try real hard though) */
        list_free(qualsofar);
    }

    if (list_length(bestpaths) == 1)
        return (Path *) linitial(bestpaths);    /* no need for AND */
    return (Path *) create_bitmap_and_path(root, rel, bestpaths);
}

classify_index_clause_usage()

static PathClauseUsage * classify_index_clause_usage ( Path *  path, List **  clauselist  )

static

Definition at line 1700 of file indxpath.c.

References bms_add_member(), PathClauseUsage::clauseids, find_indexpath_quals(), find_list_position(), lfirst, NIL, palloc(), PathClauseUsage::path, PathClauseUsage::preds, and PathClauseUsage::quals.

Referenced by choose_bitmap_and().

{
    PathClauseUsage *result;
    Bitmapset  *clauseids;
    ListCell   *lc;

    result = (PathClauseUsage *) palloc(sizeof(PathClauseUsage));
    result->path = path;

    /* Recursively find the quals and preds used by the path */
    result->quals = NIL;
    result->preds = NIL;
    find_indexpath_quals(path, &result->quals, &result->preds);

    /* Build up a bitmapset representing the quals and preds */
    clauseids = NULL;
    foreach(lc, result->quals)
    {
        Node       *node = (Node *) lfirst(lc);

        clauseids = bms_add_member(clauseids,
                                   find_list_position(node, clauselist));
    }
    foreach(lc, result->preds)
    {
        Node       *node = (Node *) lfirst(lc);

        clauseids = bms_add_member(clauseids,
                                   find_list_position(node, clauselist));
    }
    result->clauseids = clauseids;

    return result;
}

consider_index_join_clauses()

static void consider_index_join_clauses ( PlannerInfo *  root, RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  rclauseset, IndexClauseSet *  jclauseset, IndexClauseSet *  eclauseset, List **  bitindexpaths  )

static

Definition at line 437 of file indxpath.c.

References consider_index_join_outer_rels(), IndexClauseSet::indexclauses, list_length(), IndexOptInfo::ncolumns, and NIL.

Referenced by create_index_paths().

{
    int         considered_clauses = 0;
    List       *considered_relids = NIL;
    int         indexcol;

    /*
     * The strategy here is to identify every potentially useful set of outer
     * rels that can provide indexable join clauses.  For each such set,
     * select all the join clauses available from those outer rels, add on all
     * the indexable restriction clauses, and generate plain and/or bitmap
     * index paths for that set of clauses.  This is based on the assumption
     * that it's always better to apply a clause as an indexqual than as a
     * filter (qpqual); which is where an available clause would end up being
     * applied if we omit it from the indexquals.
     *
     * This looks expensive, but in most practical cases there won't be very
     * many distinct sets of outer rels to consider.  As a safety valve when
     * that's not true, we use a heuristic: limit the number of outer rel sets
     * considered to a multiple of the number of clauses considered.  (We'll
     * always consider using each individual join clause, though.)
     *
     * For simplicity in selecting relevant clauses, we represent each set of
     * outer rels as a maximum set of clause_relids --- that is, the indexed
     * relation itself is also included in the relids set.  considered_relids
     * lists all relids sets we've already tried.
     */
    for (indexcol = 0; indexcol < index->ncolumns; indexcol++)
    {
        /* Consider each applicable simple join clause */
        considered_clauses += list_length(jclauseset->indexclauses[indexcol]);
        consider_index_join_outer_rels(root, rel, index,
                                       rclauseset, jclauseset, eclauseset,
                                       bitindexpaths,
                                       jclauseset->indexclauses[indexcol],
                                       considered_clauses,
                                       &considered_relids);
        /* Consider each applicable eclass join clause */
        considered_clauses += list_length(eclauseset->indexclauses[indexcol]);
        consider_index_join_outer_rels(root, rel, index,
                                       rclauseset, jclauseset, eclauseset,
                                       bitindexpaths,
                                       eclauseset->indexclauses[indexcol],
                                       considered_clauses,
                                       &considered_relids);
    }
}

consider_index_join_outer_rels()

static void consider_index_join_outer_rels ( PlannerInfo *  root, RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  rclauseset, IndexClauseSet *  jclauseset, IndexClauseSet *  eclauseset, List **  bitindexpaths, List *  indexjoinclauses, int  considered_clauses, List **  considered_relids  )

static

Definition at line 503 of file indxpath.c.

References BMS_DIFFERENT, bms_equal_any(), bms_subset_compare(), bms_union(), RestrictInfo::clause_relids, eclass_already_used(), get_join_index_paths(), lfirst, list_length(), and RestrictInfo::parent_ec.

Referenced by consider_index_join_clauses().

{
    ListCell   *lc;

    /* Examine relids of each joinclause in the given list */
    foreach(lc, indexjoinclauses)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
        Relids      clause_relids = rinfo->clause_relids;
        ListCell   *lc2;

        /* If we already tried its relids set, no need to do so again */
        if (bms_equal_any(clause_relids, *considered_relids))
            continue;

        /*
         * Generate the union of this clause's relids set with each
         * previously-tried set.  This ensures we try this clause along with
         * every interesting subset of previous clauses.  However, to avoid
         * exponential growth of planning time when there are many clauses,
         * limit the number of relid sets accepted to 10 * considered_clauses.
         *
         * Note: get_join_index_paths adds entries to *considered_relids, but
         * it prepends them to the list, so that we won't visit new entries
         * during the inner foreach loop.  No real harm would be done if we
         * did, since the subset check would reject them; but it would waste
         * some cycles.
         */
        foreach(lc2, *considered_relids)
        {
            Relids      oldrelids = (Relids) lfirst(lc2);

            /*
             * If either is a subset of the other, no new set is possible.
             * This isn't a complete test for redundancy, but it's easy and
             * cheap.  get_join_index_paths will check more carefully if we
             * already generated the same relids set.
             */
            if (bms_subset_compare(clause_relids, oldrelids) != BMS_DIFFERENT)
                continue;

            /*
             * If this clause was derived from an equivalence class, the
             * clause list may contain other clauses derived from the same
             * eclass.  We should not consider that combining this clause with
             * one of those clauses generates a usefully different
             * parameterization; so skip if any clause derived from the same
             * eclass would already have been included when using oldrelids.
             */
            if (rinfo->parent_ec &&
                eclass_already_used(rinfo->parent_ec, oldrelids,
                                    indexjoinclauses))
                continue;

            /*
             * If the number of relid sets considered exceeds our heuristic
             * limit, stop considering combinations of clauses.  We'll still
             * consider the current clause alone, though (below this loop).
             */
            if (list_length(*considered_relids) >= 10 * considered_clauses)
                break;

            /* OK, try the union set */
            get_join_index_paths(root, rel, index,
                                 rclauseset, jclauseset, eclauseset,
                                 bitindexpaths,
                                 bms_union(clause_relids, oldrelids),
                                 considered_relids);
        }

        /* Also try this set of relids by itself */
        get_join_index_paths(root, rel, index,
                             rclauseset, jclauseset, eclauseset,
                             bitindexpaths,
                             clause_relids,
                             considered_relids);
    }
}

create_index_paths()

void create_index_paths	(	PlannerInfo *	root,
		RelOptInfo *	rel
	)

Definition at line 230 of file indxpath.c.

References add_path(), Assert, RelOptInfo::baserestrictinfo, bms_equal_any(), bms_is_subset(), choose_bitmap_and(), consider_index_join_clauses(), RelOptInfo::consider_parallel, create_bitmap_heap_path(), create_partial_bitmap_paths(), forboth, generate_bitmap_or_paths(), get_bitmap_tree_required_outer(), get_index_paths(), get_loop_count(), INDEX_MAX_KEYS, RelOptInfo::indexlist, IndexOptInfo::indpred, lappend(), RelOptInfo::lateral_relids, lfirst, list_concat(), match_eclass_clauses_to_index(), match_join_clauses_to_index(), match_restriction_clauses_to_index(), MemSet, IndexOptInfo::ncolumns, NIL, IndexClauseSet::nonempty, IndexOptInfo::predOK, and RelOptInfo::relid.

Referenced by set_plain_rel_pathlist().

{
    List       *indexpaths;
    List       *bitindexpaths;
    List       *bitjoinpaths;
    List       *joinorclauses;
    IndexClauseSet rclauseset;
    IndexClauseSet jclauseset;
    IndexClauseSet eclauseset;
    ListCell   *lc;

    /* Skip the whole mess if no indexes */
    if (rel->indexlist == NIL)
        return;

    /* Bitmap paths are collected and then dealt with at the end */
    bitindexpaths = bitjoinpaths = joinorclauses = NIL;

    /* Examine each index in turn */
    foreach(lc, rel->indexlist)
    {
        IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);

        /* Protect limited-size array in IndexClauseSets */
        Assert(index->ncolumns <= INDEX_MAX_KEYS);

        /*
         * Ignore partial indexes that do not match the query.
         * (generate_bitmap_or_paths() might be able to do something with
         * them, but that's of no concern here.)
         */
        if (index->indpred != NIL && !index->predOK)
            continue;

        /*
         * Identify the restriction clauses that can match the index.
         */
        MemSet(&rclauseset, 0, sizeof(rclauseset));
        match_restriction_clauses_to_index(rel, index, &rclauseset);

        /*
         * Build index paths from the restriction clauses.  These will be
         * non-parameterized paths.  Plain paths go directly to add_path(),
         * bitmap paths are added to bitindexpaths to be handled below.
         */
        get_index_paths(root, rel, index, &rclauseset,
                        &bitindexpaths);

        /*
         * Identify the join clauses that can match the index.  For the moment
         * we keep them separate from the restriction clauses.  Note that this
         * step finds only "loose" join clauses that have not been merged into
         * EquivalenceClasses.  Also, collect join OR clauses for later.
         */
        MemSet(&jclauseset, 0, sizeof(jclauseset));
        match_join_clauses_to_index(root, rel, index,
                                    &jclauseset, &joinorclauses);

        /*
         * Look for EquivalenceClasses that can generate joinclauses matching
         * the index.
         */
        MemSet(&eclauseset, 0, sizeof(eclauseset));
        match_eclass_clauses_to_index(root, index,
                                      &eclauseset);

        /*
         * If we found any plain or eclass join clauses, build parameterized
         * index paths using them.
         */
        if (jclauseset.nonempty || eclauseset.nonempty)
            consider_index_join_clauses(root, rel, index,
                                        &rclauseset,
                                        &jclauseset,
                                        &eclauseset,
                                        &bitjoinpaths);
    }

    /*
     * 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);
    bitindexpaths = list_concat(bitindexpaths, indexpaths);

    /*
     * Likewise, generate BitmapOrPaths for any suitable OR-clauses present in
     * the joinclause list.  Add these to bitjoinpaths.
     */
    indexpaths = generate_bitmap_or_paths(root, rel,
                                          joinorclauses, rel->baserestrictinfo);
    bitjoinpaths = list_concat(bitjoinpaths, indexpaths);

    /*
     * If we found anything usable, generate a BitmapHeapPath for the most
     * promising combination of restriction bitmap index paths.  Note there
     * will be only one such path no matter how many indexes exist.  This
     * should be sufficient since there's basically only one figure of merit
     * (total cost) for such a path.
     */
    if (bitindexpaths != NIL)
    {
        Path       *bitmapqual;
        BitmapHeapPath *bpath;

        bitmapqual = choose_bitmap_and(root, rel, bitindexpaths);
        bpath = create_bitmap_heap_path(root, rel, bitmapqual,
                                        rel->lateral_relids, 1.0, 0);
        add_path(rel, (Path *) bpath);

        /* create a partial bitmap heap path */
        if (rel->consider_parallel && rel->lateral_relids == NULL)
            create_partial_bitmap_paths(root, rel, bitmapqual);
    }

    /*
     * Likewise, if we found anything usable, generate BitmapHeapPaths for the
     * most promising combinations of join bitmap index paths.  Our strategy
     * is to generate one such path for each distinct parameterization seen
     * among the available bitmap index paths.  This may look pretty
     * expensive, but usually there won't be very many distinct
     * parameterizations.  (This logic is quite similar to that in
     * consider_index_join_clauses, but we're working with whole paths not
     * individual clauses.)
     */
    if (bitjoinpaths != NIL)
    {
        List       *path_outer;
        List       *all_path_outers;
        ListCell   *lc;

        /*
         * path_outer holds the parameterization of each path in bitjoinpaths
         * (to save recalculating that several times), while all_path_outers
         * holds all distinct parameterization sets.
         */
        path_outer = all_path_outers = NIL;
        foreach(lc, bitjoinpaths)
        {
            Path       *path = (Path *) lfirst(lc);
            Relids      required_outer;

            required_outer = get_bitmap_tree_required_outer(path);
            path_outer = lappend(path_outer, required_outer);
            if (!bms_equal_any(required_outer, all_path_outers))
                all_path_outers = lappend(all_path_outers, required_outer);
        }

        /* Now, for each distinct parameterization set ... */
        foreach(lc, all_path_outers)
        {
            Relids      max_outers = (Relids) lfirst(lc);
            List       *this_path_set;
            Path       *bitmapqual;
            Relids      required_outer;
            double      loop_count;
            BitmapHeapPath *bpath;
            ListCell   *lcp;
            ListCell   *lco;

            /* Identify all the bitmap join paths needing no more than that */
            this_path_set = NIL;
            forboth(lcp, bitjoinpaths, lco, path_outer)
            {
                Path       *path = (Path *) lfirst(lcp);
                Relids      p_outers = (Relids) lfirst(lco);

                if (bms_is_subset(p_outers, max_outers))
                    this_path_set = lappend(this_path_set, path);
            }

            /*
             * Add in restriction bitmap paths, since they can be used
             * together with any join paths.
             */
            this_path_set = list_concat(this_path_set, bitindexpaths);

            /* Select best AND combination for this parameterization */
            bitmapqual = choose_bitmap_and(root, rel, this_path_set);

            /* And push that path into the mix */
            required_outer = get_bitmap_tree_required_outer(bitmapqual);
            loop_count = get_loop_count(root, rel->relid, required_outer);
            bpath = create_bitmap_heap_path(root, rel, bitmapqual,
                                            required_outer, loop_count, 0);
            add_path(rel, (Path *) bpath);
        }
    }
}

ec_member_matches_indexcol()

static bool ec_member_matches_indexcol ( PlannerInfo *  root, RelOptInfo *  rel, EquivalenceClass *  ec, EquivalenceMember *  em, void *  arg  )

static

Definition at line 2928 of file indxpath.c.

References Assert, EquivalenceClass::ec_collation, EquivalenceClass::ec_opfamilies, EquivalenceMember::em_expr, IndexOptInfo::indexcollations, IndexCollMatchesExprColl, list_member_oid(), match_index_to_operand(), IndexOptInfo::opfamily, and IndexOptInfo::relam.

Referenced by match_eclass_clauses_to_index().

{
    IndexOptInfo *index = ((ec_member_matches_arg *) arg)->index;
    int         indexcol = ((ec_member_matches_arg *) arg)->indexcol;
    Oid         curFamily;
    Oid         curCollation;

    Assert(indexcol < index->nkeycolumns);

    curFamily = index->opfamily[indexcol];
    curCollation = index->indexcollations[indexcol];

    /*
     * If it's a btree index, we can reject it if its opfamily isn't
     * compatible with the EC, since no clause generated from the EC could be
     * used with the index.  For non-btree indexes, we can't easily tell
     * whether clauses generated from the EC could be used with the index, so
     * don't check the opfamily.  This might mean we return "true" for a
     * useless EC, so we have to recheck the results of
     * generate_implied_equalities_for_column; see
     * match_eclass_clauses_to_index.
     */
    if (index->relam == BTREE_AM_OID &&
        !list_member_oid(ec->ec_opfamilies, curFamily))
        return false;

    /* We insist on collation match for all index types, though */
    if (!IndexCollMatchesExprColl(curCollation, ec->ec_collation))
        return false;

    return match_index_to_operand((Node *) em->em_expr, indexcol, index);
}

eclass_already_used()

static bool eclass_already_used ( EquivalenceClass *  parent_ec, Relids  oldrelids, List *  indexjoinclauses  )

static

Definition at line 683 of file indxpath.c.

References bms_is_subset(), RestrictInfo::clause_relids, lfirst, and RestrictInfo::parent_ec.

Referenced by consider_index_join_outer_rels().

{
    ListCell   *lc;

    foreach(lc, indexjoinclauses)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

        if (rinfo->parent_ec == parent_ec &&
            bms_is_subset(rinfo->clause_relids, oldrelids))
            return true;
    }
    return false;
}

expand_boolean_index_clause()

static Expr * expand_boolean_index_clause ( Node *  clause, int  indexcol, IndexOptInfo *  index  )

static

Definition at line 3642 of file indxpath.c.

References arg, BooleanTest::arg, Assert, BooleanTest::booltesttype, get_notclausearg(), InvalidOid, IS_FALSE, IS_TRUE, IsA, make_opclause(), makeBoolConst(), match_index_to_operand(), and not_clause().

Referenced by expand_indexqual_conditions().

{
    /* 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),
                             InvalidOid, InvalidOid);
    }
    /* 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),
                             InvalidOid, InvalidOid);
    }
    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),
                                 InvalidOid, InvalidOid);
        }
        if (btest->booltesttype == IS_FALSE)
        {
            /* convert to indexkey = FALSE */
            return make_opclause(BooleanEqualOperator, BOOLOID, false,
                                 (Expr *) arg,
                                 (Expr *) makeBoolConst(false, false),
                                 InvalidOid, InvalidOid);
        }
        /* Oops */
        Assert(false);
    }

    return NULL;
}

expand_indexqual_conditions()

void expand_indexqual_conditions	(	IndexOptInfo *	index,
		List *	indexclauses,
		List *	indexclausecols,
		List **	indexquals_p,
		List **	indexqualcols_p
	)

Definition at line 3552 of file indxpath.c.

References IndexOptInfo::amsearchnulls, Assert, RestrictInfo::clause, elog, ERROR, expand_boolean_index_clause(), expand_indexqual_opclause(), expand_indexqual_rowcompare(), forboth, IndexOptInfo::indexcollations, is_opclause, IsA, lappend(), lappend_int(), lfirst, lfirst_int, list_concat(), list_length(), make_simple_restrictinfo, NIL, nodeTag, and IndexOptInfo::opfamily.

Referenced by create_index_path().

{
    List       *indexquals = NIL;
    List       *indexqualcols = NIL;
    ListCell   *lcc,
               *lci;

    forboth(lcc, indexclauses, lci, indexclausecols)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lcc);
        int         indexcol = lfirst_int(lci);
        Expr       *clause = rinfo->clause;
        Oid         curFamily;
        Oid         curCollation;

        Assert(indexcol < index->nkeycolumns);

        curFamily = index->opfamily[indexcol];
        curCollation = index->indexcollations[indexcol];

        /* First check for boolean cases */
        if (IsBooleanOpfamily(curFamily))
        {
            Expr       *boolqual;

            boolqual = expand_boolean_index_clause((Node *) clause,
                                                   indexcol,
                                                   index);
            if (boolqual)
            {
                indexquals = lappend(indexquals,
                                     make_simple_restrictinfo(boolqual));
                indexqualcols = lappend_int(indexqualcols, indexcol);
                continue;
            }
        }

        /*
         * Else it must be an opclause (usual case), ScalarArrayOp,
         * RowCompare, or NullTest
         */
        if (is_opclause(clause))
        {
            indexquals = list_concat(indexquals,
                                     expand_indexqual_opclause(rinfo,
                                                               curFamily,
                                                               curCollation));
            /* expand_indexqual_opclause can produce multiple clauses */
            while (list_length(indexqualcols) < list_length(indexquals))
                indexqualcols = lappend_int(indexqualcols, indexcol);
        }
        else if (IsA(clause, ScalarArrayOpExpr))
        {
            /* no extra work at this time */
            indexquals = lappend(indexquals, rinfo);
            indexqualcols = lappend_int(indexqualcols, indexcol);
        }
        else if (IsA(clause, RowCompareExpr))
        {
            indexquals = lappend(indexquals,
                                 expand_indexqual_rowcompare(rinfo,
                                                             index,
                                                             indexcol));
            indexqualcols = lappend_int(indexqualcols, indexcol);
        }
        else if (IsA(clause, NullTest))
        {
            Assert(index->amsearchnulls);
            indexquals = lappend(indexquals, rinfo);
            indexqualcols = lappend_int(indexqualcols, indexcol);
        }
        else
            elog(ERROR, "unsupported indexqual type: %d",
                 (int) nodeTag(clause));
    }

    *indexquals_p = indexquals;
    *indexqualcols_p = indexqualcols;
}

expand_indexqual_opclause()

static List * expand_indexqual_opclause ( RestrictInfo *  rinfo, Oid  opfamily, Oid  idxcollation  )

static

Definition at line 3708 of file indxpath.c.

References RestrictInfo::clause, Const::constvalue, get_leftop(), get_rightop(), list_make1, network_prefix_quals(), op_in_opfamily(), pattern_fixed_prefix(), Pattern_Type_Like, Pattern_Type_Like_IC, Pattern_Type_Regex, Pattern_Type_Regex_IC, and prefix_quals().

Referenced by expand_indexqual_conditions().

{
    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;
    Oid         expr_coll = ((OpExpr *) clause)->inputcollid;
    Const      *patt = (Const *) rightop;
    Const      *prefix = NULL;
    Pattern_Prefix_Status pstatus;

    /*
     * LIKE and regex operators are not members of any btree index opfamily,
     * but they can be members of opfamilies for more exotic index types such
     * as GIN.  Therefore, we should only do expansion if the operator is
     * actually not in the opfamily.  But checking that requires a syscache
     * lookup, so it's best to first see if the operator is one we are
     * interested in.
     */
    switch (expr_op)
    {
        case OID_TEXT_LIKE_OP:
        case OID_BPCHAR_LIKE_OP:
        case OID_NAME_LIKE_OP:
        case OID_BYTEA_LIKE_OP:
            if (!op_in_opfamily(expr_op, opfamily))
            {
                pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like, expr_coll,
                                               &prefix, NULL);
                return prefix_quals(leftop, opfamily, idxcollation, prefix, pstatus);
            }
            break;

        case OID_TEXT_ICLIKE_OP:
        case OID_BPCHAR_ICLIKE_OP:
        case OID_NAME_ICLIKE_OP:
            if (!op_in_opfamily(expr_op, opfamily))
            {
                /* the right-hand const is type text for all of these */
                pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like_IC, expr_coll,
                                               &prefix, NULL);
                return prefix_quals(leftop, opfamily, idxcollation, prefix, pstatus);
            }
            break;

        case OID_TEXT_REGEXEQ_OP:
        case OID_BPCHAR_REGEXEQ_OP:
        case OID_NAME_REGEXEQ_OP:
            if (!op_in_opfamily(expr_op, opfamily))
            {
                /* the right-hand const is type text for all of these */
                pstatus = pattern_fixed_prefix(patt, Pattern_Type_Regex, expr_coll,
                                               &prefix, NULL);
                return prefix_quals(leftop, opfamily, idxcollation, prefix, pstatus);
            }
            break;

        case OID_TEXT_ICREGEXEQ_OP:
        case OID_BPCHAR_ICREGEXEQ_OP:
        case OID_NAME_ICREGEXEQ_OP:
            if (!op_in_opfamily(expr_op, opfamily))
            {
                /* the right-hand const is type text for all of these */
                pstatus = pattern_fixed_prefix(patt, Pattern_Type_Regex_IC, expr_coll,
                                               &prefix, NULL);
                return prefix_quals(leftop, opfamily, idxcollation, prefix, pstatus);
            }
            break;

        case OID_INET_SUB_OP:
        case OID_INET_SUBEQ_OP:
            if (!op_in_opfamily(expr_op, opfamily))
            {
                return network_prefix_quals(leftop, expr_op, opfamily,
                                            patt->constvalue);
            }
            break;
    }

    /* Default case: just make a list of the unmodified indexqual */
    return list_make1(rinfo);
}

expand_indexqual_rowcompare()

static RestrictInfo * expand_indexqual_rowcompare ( RestrictInfo *  rinfo, IndexOptInfo *  index, int  indexcol  )

static

Definition at line 3802 of file indxpath.c.

References adjust_rowcompare_for_index(), RestrictInfo::clause, and make_simple_restrictinfo.

Referenced by expand_indexqual_conditions().

{
    RowCompareExpr *clause = (RowCompareExpr *) rinfo->clause;
    Expr       *newclause;
    List       *indexcolnos;
    bool        var_on_left;

    newclause = adjust_rowcompare_for_index(clause,
                                            index,
                                            indexcol,
                                            &indexcolnos,
                                            &var_on_left);

    /*
     * If we didn't have to change the RowCompareExpr, return the original
     * RestrictInfo.
     */
    if (newclause == (Expr *) clause)
        return rinfo;

    /* Else we need a new RestrictInfo */
    return make_simple_restrictinfo(newclause);
}

find_indexpath_quals()

static void find_indexpath_quals ( Path *  bitmapqual, List **  quals, List **  preds  )

static

Definition at line 1795 of file indxpath.c.

References BitmapAndPath::bitmapquals, BitmapOrPath::bitmapquals, elog, ERROR, get_actual_clauses(), IndexPath::indexclauses, IndexPath::indexinfo, IndexOptInfo::indpred, IsA, lfirst, list_concat(), list_copy(), and nodeTag.

Referenced by classify_index_clause_usage().

{
    if (IsA(bitmapqual, BitmapAndPath))
    {
        BitmapAndPath *apath = (BitmapAndPath *) bitmapqual;
        ListCell   *l;

        foreach(l, apath->bitmapquals)
        {
            find_indexpath_quals((Path *) lfirst(l), quals, preds);
        }
    }
    else if (IsA(bitmapqual, BitmapOrPath))
    {
        BitmapOrPath *opath = (BitmapOrPath *) bitmapqual;
        ListCell   *l;

        foreach(l, opath->bitmapquals)
        {
            find_indexpath_quals((Path *) lfirst(l), quals, preds);
        }
    }
    else if (IsA(bitmapqual, IndexPath))
    {
        IndexPath  *ipath = (IndexPath *) bitmapqual;

        *quals = list_concat(*quals, get_actual_clauses(ipath->indexclauses));
        *preds = list_concat(*preds, list_copy(ipath->indexinfo->indpred));
    }
    else
        elog(ERROR, "unrecognized node type: %d", nodeTag(bitmapqual));
}

find_list_position()

static int find_list_position ( Node *  node, List **  nodelist  )

static

Definition at line 1836 of file indxpath.c.

References equal(), i, lappend(), and lfirst.

Referenced by classify_index_clause_usage().

{
    int         i;
    ListCell   *lc;

    i = 0;
    foreach(lc, *nodelist)
    {
        Node       *oldnode = (Node *) lfirst(lc);

        if (equal(node, oldnode))
            return i;
        i++;
    }

    *nodelist = lappend(*nodelist, node);

    return i;
}

generate_bitmap_or_paths()

static List * generate_bitmap_or_paths ( PlannerInfo *  root, RelOptInfo *  rel, List *  clauses, List *  other_clauses  )

static

Definition at line 1263 of file indxpath.c.

References and_clause(), Assert, build_paths_for_OR(), castNode, choose_bitmap_and(), create_bitmap_or_path(), lappend(), lfirst, lfirst_node, list_concat(), list_copy(), list_make1, NIL, RestrictInfo::orclause, and restriction_is_or_clause().

Referenced by create_index_paths().

{
    List       *result = NIL;
    List       *all_clauses;
    ListCell   *lc;

    /*
     * We can use both the current and other clauses as context for
     * build_paths_for_OR; no need to remove ORs from the lists.
     */
    all_clauses = list_concat(list_copy(clauses), other_clauses);

    foreach(lc, clauses)
    {
        RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
        List       *pathlist;
        Path       *bitmapqual;
        ListCell   *j;

        /* Ignore RestrictInfos that aren't ORs */
        if (!restriction_is_or_clause(rinfo))
            continue;

        /*
         * 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 = build_paths_for_OR(root, rel,
                                             andargs,
                                             all_clauses);

                /* Recurse in case there are sub-ORs */
                indlist = list_concat(indlist,
                                      generate_bitmap_or_paths(root, rel,
                                                               andargs,
                                                               all_clauses));
            }
            else
            {
                RestrictInfo *rinfo = castNode(RestrictInfo, orarg);
                List       *orargs;

                Assert(!restriction_is_or_clause(rinfo));
                orargs = list_make1(rinfo);

                indlist = build_paths_for_OR(root, rel,
                                             orargs,
                                             all_clauses);
            }

            /*
             * If nothing matched this arm, we can't do anything with this OR
             * clause.
             */
            if (indlist == NIL)
            {
                pathlist = NIL;
                break;
            }

            /*
             * OK, pick the most promising AND combination, and add it to
             * pathlist.
             */
            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;
}

get_bitmap_tree_required_outer()

static Relids get_bitmap_tree_required_outer ( Path *  bitmapqual )

static

Definition at line 1747 of file indxpath.c.

References bms_copy(), bms_join(), elog, ERROR, IsA, lfirst, nodeTag, and PATH_REQ_OUTER.

Referenced by bitmap_and_cost_est(), bitmap_scan_cost_est(), and create_index_paths().

{
    Relids      result = NULL;
    ListCell   *lc;

    if (IsA(bitmapqual, IndexPath))
    {
        return bms_copy(PATH_REQ_OUTER(bitmapqual));
    }
    else if (IsA(bitmapqual, BitmapAndPath))
    {
        foreach(lc, ((BitmapAndPath *) bitmapqual)->bitmapquals)
        {
            result = bms_join(result,
                              get_bitmap_tree_required_outer((Path *) lfirst(lc)));
        }
    }
    else if (IsA(bitmapqual, BitmapOrPath))
    {
        foreach(lc, ((BitmapOrPath *) bitmapqual)->bitmapquals)
        {
            result = bms_join(result,
                              get_bitmap_tree_required_outer((Path *) lfirst(lc)));
        }
    }
    else
        elog(ERROR, "unrecognized node type: %d", nodeTag(bitmapqual));

    return result;
}

get_index_paths()

static void get_index_paths ( PlannerInfo *  root, RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  clauses, List **  bitindexpaths  )

static

Definition at line 735 of file indxpath.c.

References add_path(), IndexOptInfo::amhasgetbitmap, IndexOptInfo::amhasgettuple, build_index_paths(), lappend(), lfirst, list_concat(), NIL, Path::pathkeys, IndexOptInfo::predOK, ST_ANYSCAN, and ST_BITMAPSCAN.

Referenced by create_index_paths(), and get_join_index_paths().

{
    List       *indexpaths;
    bool        skip_nonnative_saop = false;
    bool        skip_lower_saop = false;
    ListCell   *lc;

    /*
     * Build simple index paths using the clauses.  Allow ScalarArrayOpExpr
     * clauses only if the index AM supports them natively, and skip any such
     * clauses for index columns after the first (so that we produce ordered
     * paths if possible).
     */
    indexpaths = build_index_paths(root, rel,
                                   index, clauses,
                                   index->predOK,
                                   ST_ANYSCAN,
                                   &skip_nonnative_saop,
                                   &skip_lower_saop);

    /*
     * If we skipped any lower-order ScalarArrayOpExprs on an index with an AM
     * that supports them, then try again including those clauses.  This will
     * produce paths with more selectivity but no ordering.
     */
    if (skip_lower_saop)
    {
        indexpaths = list_concat(indexpaths,
                                 build_index_paths(root, rel,
                                                   index, clauses,
                                                   index->predOK,
                                                   ST_ANYSCAN,
                                                   &skip_nonnative_saop,
                                                   NULL));
    }

    /*
     * Submit all the ones that can form plain IndexScan plans to add_path. (A
     * plain IndexPath can represent either a plain IndexScan or an
     * IndexOnlyScan, but for our purposes here that distinction does not
     * matter.  However, some of the indexes might support only bitmap scans,
     * and those we mustn't submit to add_path here.)
     *
     * Also, pick out the ones that are usable as bitmap scans.  For that, we
     * must discard indexes that don't support bitmap scans, and we also are
     * only interested in paths that have some selectivity; we should discard
     * anything that was generated solely for ordering purposes.
     */
    foreach(lc, indexpaths)
    {
        IndexPath  *ipath = (IndexPath *) lfirst(lc);

        if (index->amhasgettuple)
            add_path(rel, (Path *) ipath);

        if (index->amhasgetbitmap &&
            (ipath->path.pathkeys == NIL ||
             ipath->indexselectivity < 1.0))
            *bitindexpaths = lappend(*bitindexpaths, ipath);
    }

    /*
     * If there were ScalarArrayOpExpr clauses that the index can't handle
     * natively, generate bitmap scan paths relying on executor-managed
     * ScalarArrayOpExpr.
     */
    if (skip_nonnative_saop)
    {
        indexpaths = build_index_paths(root, rel,
                                       index, clauses,
                                       false,
                                       ST_BITMAPSCAN,
                                       NULL,
                                       NULL);
        *bitindexpaths = list_concat(*bitindexpaths, indexpaths);
    }
}

get_join_index_paths()

static void get_join_index_paths ( PlannerInfo *  root, RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  rclauseset, IndexClauseSet *  jclauseset, IndexClauseSet *  eclauseset, List **  bitindexpaths, Relids  relids, List **  considered_relids  )

static

Definition at line 604 of file indxpath.c.

References Assert, bms_equal_any(), bms_is_subset(), RestrictInfo::clause_relids, get_index_paths(), IndexClauseSet::indexclauses, lappend(), lcons(), lfirst, list_concat(), MemSet, IndexOptInfo::ncolumns, NIL, and IndexClauseSet::nonempty.

Referenced by consider_index_join_outer_rels().

{
    IndexClauseSet clauseset;
    int         indexcol;

    /* If we already considered this relids set, don't repeat the work */
    if (bms_equal_any(relids, *considered_relids))
        return;

    /* Identify indexclauses usable with this relids set */
    MemSet(&clauseset, 0, sizeof(clauseset));

    for (indexcol = 0; indexcol < index->ncolumns; indexcol++)
    {
        ListCell   *lc;

        /* First find applicable simple join clauses */
        foreach(lc, jclauseset->indexclauses[indexcol])
        {
            RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

            if (bms_is_subset(rinfo->clause_relids, relids))
                clauseset.indexclauses[indexcol] =
                    lappend(clauseset.indexclauses[indexcol], rinfo);
        }

        /*
         * Add applicable eclass join clauses.  The clauses generated for each
         * column are redundant (cf generate_implied_equalities_for_column),
         * so we need at most one.  This is the only exception to the general
         * rule of using all available index clauses.
         */
        foreach(lc, eclauseset->indexclauses[indexcol])
        {
            RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

            if (bms_is_subset(rinfo->clause_relids, relids))
            {
                clauseset.indexclauses[indexcol] =
                    lappend(clauseset.indexclauses[indexcol], rinfo);
                break;
            }
        }

        /* Add restriction clauses (this is nondestructive to rclauseset) */
        clauseset.indexclauses[indexcol] =
            list_concat(clauseset.indexclauses[indexcol],
                        rclauseset->indexclauses[indexcol]);

        if (clauseset.indexclauses[indexcol] != NIL)
            clauseset.nonempty = true;
    }

    /* We should have found something, else caller passed silly relids */
    Assert(clauseset.nonempty);

    /* Build index path(s) using the collected set of clauses */
    get_index_paths(root, rel, index, &clauseset, bitindexpaths);

    /*
     * Remember we considered paths for this set of relids.  We use lcons not
     * lappend to avoid confusing the loop in consider_index_join_outer_rels.
     */
    *considered_relids = lcons(relids, *considered_relids);
}

get_loop_count()

static double get_loop_count ( PlannerInfo *  root, Index  cur_relid, Relids  outer_relids  )

static

Definition at line 1974 of file indxpath.c.

References adjust_rowcount_for_semijoins(), Assert, bms_next_member(), IS_DUMMY_REL, RelOptInfo::relid, RelOptInfo::rows, PlannerInfo::simple_rel_array, and PlannerInfo::simple_rel_array_size.

Referenced by bitmap_and_cost_est(), bitmap_scan_cost_est(), build_index_paths(), and create_index_paths().

{
    double      result;
    int         outer_relid;

    /* For a non-parameterized path, just return 1.0 quickly */
    if (outer_relids == NULL)
        return 1.0;

    result = 0.0;
    outer_relid = -1;
    while ((outer_relid = bms_next_member(outer_relids, outer_relid)) >= 0)
    {
        RelOptInfo *outer_rel;
        double      rowcount;

        /* Paranoia: ignore bogus relid indexes */
        if (outer_relid >= root->simple_rel_array_size)
            continue;
        outer_rel = root->simple_rel_array[outer_relid];
        if (outer_rel == NULL)
            continue;
        Assert(outer_rel->relid == outer_relid);    /* sanity check on array */

        /* Other relation could be proven empty, if so ignore */
        if (IS_DUMMY_REL(outer_rel))
            continue;

        /* Otherwise, rel's rows estimate should be valid by now */
        Assert(outer_rel->rows > 0);

        /* Check to see if rel is on the inside of any semijoins */
        rowcount = adjust_rowcount_for_semijoins(root,
                                                 cur_relid,
                                                 outer_relid,
                                                 outer_rel->rows);

        /* Remember smallest row count estimate among the outer rels */
        if (result == 0.0 || result > rowcount)
            result = rowcount;
    }
    /* Return 1.0 if we found no valid relations (shouldn't happen) */
    return (result > 0.0) ? result : 1.0;
}

indexcol_is_bool_constant_for_query()

bool indexcol_is_bool_constant_for_query	(	IndexOptInfo *	index,
		int	indexcol
	)

Definition at line 3157 of file indxpath.c.

References RelOptInfo::baserestrictinfo, RestrictInfo::clause, lfirst, match_boolean_index_clause(), IndexOptInfo::opfamily, RestrictInfo::pseudoconstant, and IndexOptInfo::rel.

Referenced by build_index_pathkeys().

{
    ListCell   *lc;

    /* If the index isn't boolean, we can't possibly get a match */
    if (!IsBooleanOpfamily(index->opfamily[indexcol]))
        return false;

    /* Check each restriction clause for the index's rel */
    foreach(lc, index->rel->baserestrictinfo)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

        /*
         * As in match_clause_to_indexcol, never match pseudoconstants to
         * indexes.  (It might be semantically okay to do so here, but the
         * odds of getting a match are negligible, so don't waste the cycles.)
         */
        if (rinfo->pseudoconstant)
            continue;

        /* See if we can match the clause's expression to the index column */
        if (match_boolean_index_clause((Node *) rinfo->clause, indexcol, index))
            return true;
    }

    return false;
}

is_indexable_operator()

static bool is_indexable_operator ( Oid  expr_op, Oid  opfamily, bool  indexkey_on_left  )

static

Definition at line 2459 of file indxpath.c.

References get_commutator(), InvalidOid, and op_in_opfamily().

Referenced by match_clause_to_indexcol().

{
    /* Get the commuted operator if necessary */
    if (!indexkey_on_left)
    {
        expr_op = get_commutator(expr_op);
        if (expr_op == InvalidOid)
            return false;
    }

    /* OK if the (commuted) operator is a member of the index's opfamily */
    return op_in_opfamily(expr_op, opfamily);
}

match_boolean_index_clause()

static bool match_boolean_index_clause ( Node *  clause, int  indexcol, IndexOptInfo *  index  )

static

Definition at line 3332 of file indxpath.c.

References BooleanTest::arg, BooleanTest::booltesttype, get_notclausearg(), IS_FALSE, IS_TRUE, IsA, match_index_to_operand(), and not_clause().

Referenced by indexcol_is_bool_constant_for_query(), and match_clause_to_indexcol().

{
    /* 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_clause_to_index()

static void match_clause_to_index ( IndexOptInfo *  index, RestrictInfo *  rinfo, IndexClauseSet *  clauseset  )

static

Definition at line 2225 of file indxpath.c.

References IndexClauseSet::indexclauses, list_append_unique_ptr(), match_clause_to_indexcol(), IndexOptInfo::nkeycolumns, IndexClauseSet::nonempty, RestrictInfo::pseudoconstant, IndexOptInfo::rel, and restriction_is_securely_promotable().

Referenced by match_clauses_to_index(), and match_join_clauses_to_index().

{
    int         indexcol;

    /*
     * Never match pseudoconstants to indexes.  (Normally a match could not
     * happen anyway, since a pseudoconstant clause couldn't contain a Var,
     * but what if someone builds an expression index on a constant? It's not
     * totally unreasonable to do so with a partial index, either.)
     */
    if (rinfo->pseudoconstant)
        return;

    /*
     * If clause can't be used as an indexqual because it must wait till after
     * some lower-security-level restriction clause, reject it.
     */
    if (!restriction_is_securely_promotable(rinfo, index->rel))
        return;

    /* OK, check each index key column for a match */
    for (indexcol = 0; indexcol < index->nkeycolumns; indexcol++)
    {
        if (match_clause_to_indexcol(index,
                                     indexcol,
                                     rinfo))
        {
            clauseset->indexclauses[indexcol] =
                list_append_unique_ptr(clauseset->indexclauses[indexcol],
                                       rinfo);
            clauseset->nonempty = true;
            return;
        }
    }
}

match_clause_to_indexcol()

static bool match_clause_to_indexcol ( IndexOptInfo *  index, int  indexcol, RestrictInfo *  rinfo  )

static

Definition at line 2326 of file indxpath.c.

References IndexOptInfo::amsearchnulls, NullTest::arg, NullTest::argisrow, ScalarArrayOpExpr::args, Assert, bms_is_member(), RestrictInfo::clause, contain_volatile_functions(), get_leftop(), get_rightop(), IndexOptInfo::indexcollations, IndexCollMatchesExprColl, ScalarArrayOpExpr::inputcollid, is_indexable_operator(), is_opclause, IsA, RestrictInfo::left_relids, linitial, lsecond, match_boolean_index_clause(), match_index_to_operand(), match_rowcompare_to_indexcol(), match_special_index_operator(), IndexOptInfo::opfamily, ScalarArrayOpExpr::opno, pull_varnos(), IndexOptInfo::rel, RelOptInfo::relid, RestrictInfo::right_relids, and ScalarArrayOpExpr::useOr.

Referenced by match_clause_to_index().

{
    Expr       *clause = rinfo->clause;
    Index       index_relid = index->rel->relid;
    Oid         opfamily;
    Oid         idxcollation;
    Node       *leftop,
               *rightop;
    Relids      left_relids;
    Relids      right_relids;
    Oid         expr_op;
    Oid         expr_coll;
    bool        plain_op;

    Assert(indexcol < index->nkeycolumns);

    opfamily = index->opfamily[indexcol];
    idxcollation = index->indexcollations[indexcol];

    /* First check for boolean-index cases. */
    if (IsBooleanOpfamily(opfamily))
    {
        if (match_boolean_index_clause((Node *) clause, indexcol, index))
            return true;
    }

    /*
     * Clause must be a binary opclause, or possibly a ScalarArrayOpExpr
     * (which is always binary, by definition).  Or it could be a
     * RowCompareExpr, which we pass off to match_rowcompare_to_indexcol().
     * Or, if the index supports it, we can handle IS NULL/NOT NULL clauses.
     */
    if (is_opclause(clause))
    {
        leftop = get_leftop(clause);
        rightop = get_rightop(clause);
        if (!leftop || !rightop)
            return false;
        left_relids = rinfo->left_relids;
        right_relids = rinfo->right_relids;
        expr_op = ((OpExpr *) clause)->opno;
        expr_coll = ((OpExpr *) clause)->inputcollid;
        plain_op = true;
    }
    else if (clause && IsA(clause, ScalarArrayOpExpr))
    {
        ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;

        /* We only accept ANY clauses, not ALL */
        if (!saop->useOr)
            return false;
        leftop = (Node *) linitial(saop->args);
        rightop = (Node *) lsecond(saop->args);
        left_relids = NULL;     /* not actually needed */
        right_relids = pull_varnos(rightop);
        expr_op = saop->opno;
        expr_coll = saop->inputcollid;
        plain_op = false;
    }
    else if (clause && IsA(clause, RowCompareExpr))
    {
        return match_rowcompare_to_indexcol(index, indexcol,
                                            opfamily, idxcollation,
                                            (RowCompareExpr *) clause);
    }
    else if (index->amsearchnulls && IsA(clause, NullTest))
    {
        NullTest   *nt = (NullTest *) clause;

        if (!nt->argisrow &&
            match_index_to_operand((Node *) nt->arg, indexcol, index))
            return true;
        return false;
    }
    else
        return false;

    /*
     * Check for clauses of the form: (indexkey operator constant) or
     * (constant operator indexkey).  See above notes about const-ness.
     */
    if (match_index_to_operand(leftop, indexcol, index) &&
        !bms_is_member(index_relid, right_relids) &&
        !contain_volatile_functions(rightop))
    {
        if (IndexCollMatchesExprColl(idxcollation, expr_coll) &&
            is_indexable_operator(expr_op, opfamily, true))
            return true;

        /*
         * If we didn't find a member of the index's opfamily, see whether it
         * is a "special" indexable operator.
         */
        if (plain_op &&
            match_special_index_operator(clause, opfamily,
                                         idxcollation, true))
            return true;
        return false;
    }

    if (plain_op &&
        match_index_to_operand(rightop, indexcol, index) &&
        !bms_is_member(index_relid, left_relids) &&
        !contain_volatile_functions(leftop))
    {
        if (IndexCollMatchesExprColl(idxcollation, expr_coll) &&
            is_indexable_operator(expr_op, opfamily, false))
            return true;

        /*
         * If we didn't find a member of the index's opfamily, see whether it
         * is a "special" indexable operator.
         */
        if (match_special_index_operator(clause, opfamily,
                                         idxcollation, false))
            return true;
        return false;
    }

    return false;
}

match_clause_to_ordering_op()

static Expr * match_clause_to_ordering_op ( IndexOptInfo *  index, int  indexcol, Expr *  clause, Oid  pk_opfamily  )

static

Definition at line 2681 of file indxpath.c.

References OpExpr::args, Assert, contain_var_clause(), contain_volatile_functions(), get_commutator(), get_leftop(), get_op_opfamily_sortfamily(), get_rightop(), IndexOptInfo::indexcollations, IndexCollMatchesExprColl, InvalidOid, is_opclause, list_make2, makeNode, match_index_to_operand(), IndexOptInfo::opfamily, OpExpr::opfuncid, and OpExpr::opno.

Referenced by match_pathkeys_to_index().

{
    Oid         opfamily;
    Oid         idxcollation;
    Node       *leftop,
               *rightop;
    Oid         expr_op;
    Oid         expr_coll;
    Oid         sortfamily;
    bool        commuted;

    Assert(indexcol < index->nkeycolumns);

    opfamily = index->opfamily[indexcol];
    idxcollation = index->indexcollations[indexcol];

    /*
     * Clause must be a binary opclause.
     */
    if (!is_opclause(clause))
        return NULL;
    leftop = get_leftop(clause);
    rightop = get_rightop(clause);
    if (!leftop || !rightop)
        return NULL;
    expr_op = ((OpExpr *) clause)->opno;
    expr_coll = ((OpExpr *) clause)->inputcollid;

    /*
     * We can forget the whole thing right away if wrong collation.
     */
    if (!IndexCollMatchesExprColl(idxcollation, expr_coll))
        return NULL;

    /*
     * Check for clauses of the form: (indexkey operator constant) or
     * (constant operator indexkey).
     */
    if (match_index_to_operand(leftop, indexcol, index) &&
        !contain_var_clause(rightop) &&
        !contain_volatile_functions(rightop))
    {
        commuted = false;
    }
    else if (match_index_to_operand(rightop, indexcol, index) &&
             !contain_var_clause(leftop) &&
             !contain_volatile_functions(leftop))
    {
        /* Might match, but we need a commuted operator */
        expr_op = get_commutator(expr_op);
        if (expr_op == InvalidOid)
            return NULL;
        commuted = true;
    }
    else
        return NULL;

    /*
     * Is the (commuted) operator an ordering operator for the opfamily? And
     * if so, does it yield the right sorting semantics?
     */
    sortfamily = get_op_opfamily_sortfamily(expr_op, opfamily);
    if (sortfamily != pk_opfamily)
        return NULL;

    /* We have a match.  Return clause or a commuted version thereof. */
    if (commuted)
    {
        OpExpr     *newclause = makeNode(OpExpr);

        /* flat-copy all the fields of clause */
        memcpy(newclause, clause, sizeof(OpExpr));

        /* commute it */
        newclause->opno = expr_op;
        newclause->opfuncid = InvalidOid;
        newclause->args = list_make2(rightop, leftop);

        clause = (Expr *) newclause;
    }

    return clause;
}

match_clauses_to_index()

static void match_clauses_to_index ( IndexOptInfo *  index, List *  clauses, IndexClauseSet *  clauseset  )

static

Definition at line 2194 of file indxpath.c.

References lfirst_node, and match_clause_to_index().

Referenced by build_paths_for_OR(), match_eclass_clauses_to_index(), and match_restriction_clauses_to_index().

{
    ListCell   *lc;

    foreach(lc, clauses)
    {
        RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);

        match_clause_to_index(index, rinfo, clauseset);
    }
}

match_eclass_clauses_to_index()

static void match_eclass_clauses_to_index ( PlannerInfo *  root, IndexOptInfo *  index, IndexClauseSet *  clauseset  )

static

Definition at line 2156 of file indxpath.c.

References arg, ec_member_matches_indexcol(), generate_implied_equalities_for_column(), RelOptInfo::has_eclass_joins, ec_member_matches_arg::index, ec_member_matches_arg::indexcol, RelOptInfo::lateral_referencers, match_clauses_to_index(), IndexOptInfo::nkeycolumns, and IndexOptInfo::rel.

Referenced by create_index_paths().

{
    int         indexcol;

    /* No work if rel is not in any such ECs */
    if (!index->rel->has_eclass_joins)
        return;

    for (indexcol = 0; indexcol < index->nkeycolumns; indexcol++)
    {
        ec_member_matches_arg arg;
        List       *clauses;

        /* Generate clauses, skipping any that join to lateral_referencers */
        arg.index = index;
        arg.indexcol = indexcol;
        clauses = generate_implied_equalities_for_column(root,
                                                         index->rel,
                                                         ec_member_matches_indexcol,
                                                         (void *) &arg,
                                                         index->rel->lateral_referencers);

        /*
         * We have to check whether the results actually do match the index,
         * since for non-btree indexes the EC's equality operators might not
         * be in the index opclass (cf ec_member_matches_indexcol).
         */
        match_clauses_to_index(index, clauses, clauseset);
    }
}

match_index_to_operand()

bool match_index_to_operand	(	Node *	operand,
		int	indexcol,
		IndexOptInfo *	index
	)

Definition at line 3206 of file indxpath.c.

References arg, elog, equal(), ERROR, i, IndexOptInfo::indexkeys, IndexOptInfo::indexprs, IsA, lfirst, list_head(), lnext, IndexOptInfo::rel, and RelOptInfo::relid.

Referenced by adjust_rowcompare_for_index(), deconstruct_indexquals(), ec_member_matches_indexcol(), expand_boolean_index_clause(), get_actual_variable_range(), match_boolean_index_clause(), match_clause_to_indexcol(), match_clause_to_ordering_op(), match_rowcompare_to_indexcol(), and relation_has_unique_index_for().

{
    int         indkey;

    /*
     * 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;

    indkey = index->indexkeys[indexcol];
    if (indkey != 0)
    {
        /*
         * Simple index column; operand must be a matching Var.
         */
        if (operand && IsA(operand, Var) &&
            index->rel->relid == ((Var *) operand)->varno &&
            indkey == ((Var *) operand)->varattno)
            return true;
    }
    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;

        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);

        /*
         * Does it match the operand?  Again, strip any relabeling.
         */
        if (indexkey && IsA(indexkey, RelabelType))
            indexkey = (Node *) ((RelabelType *) indexkey)->arg;

        if (equal(indexkey, operand))
            return true;
    }

    return false;
}

match_join_clauses_to_index()

static void match_join_clauses_to_index ( PlannerInfo *  root, RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  clauseset, List **  joinorclauses  )

static

Definition at line 2126 of file indxpath.c.

References join_clause_is_movable_to(), RelOptInfo::joininfo, lappend(), lfirst, match_clause_to_index(), and restriction_is_or_clause().

Referenced by create_index_paths().

{
    ListCell   *lc;

    /* Scan the rel's join clauses */
    foreach(lc, rel->joininfo)
    {
        RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);

        /* Check if clause can be moved to this rel */
        if (!join_clause_is_movable_to(rinfo, rel))
            continue;

        /* Potentially usable, so see if it matches the index or is an OR */
        if (restriction_is_or_clause(rinfo))
            *joinorclauses = lappend(*joinorclauses, rinfo);
        else
            match_clause_to_index(index, rinfo, clauseset);
    }
}

match_pathkeys_to_index()

static void match_pathkeys_to_index ( IndexOptInfo *  index, List *  pathkeys, List **  orderby_clauses_p, List **  clause_columns_p  )

static

Definition at line 2567 of file indxpath.c.

References IndexOptInfo::amcanorderbyop, bms_equal(), BTLessStrategyNumber, EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_members, EquivalenceMember::em_expr, EquivalenceMember::em_relids, lappend(), lappend_int(), lfirst, match_clause_to_ordering_op(), member, IndexOptInfo::ncolumns, NIL, PathKey::pk_eclass, PathKey::pk_nulls_first, PathKey::pk_opfamily, PathKey::pk_strategy, IndexOptInfo::rel, and RelOptInfo::relids.

Referenced by build_index_paths().

{
    List       *orderby_clauses = NIL;
    List       *clause_columns = NIL;
    ListCell   *lc1;

    *orderby_clauses_p = NIL;   /* set default results */
    *clause_columns_p = NIL;

    /* Only indexes with the amcanorderbyop property are interesting here */
    if (!index->amcanorderbyop)
        return;

    foreach(lc1, pathkeys)
    {
        PathKey    *pathkey = (PathKey *) lfirst(lc1);
        bool        found = false;
        ListCell   *lc2;

        /*
         * Note: for any failure to match, we just return NIL immediately.
         * There is no value in matching just some of the pathkeys.
         */

        /* Pathkey must request default sort order for the target opfamily */
        if (pathkey->pk_strategy != BTLessStrategyNumber ||
            pathkey->pk_nulls_first)
            return;

        /* If eclass is volatile, no hope of using an indexscan */
        if (pathkey->pk_eclass->ec_has_volatile)
            return;

        /*
         * Try to match eclass member expression(s) to index.  Note that child
         * EC members are considered, but only when they belong to the target
         * relation.  (Unlike regular members, the same expression could be a
         * child member of more than one EC.  Therefore, the same index could
         * be considered to match more than one pathkey list, which is OK
         * here.  See also get_eclass_for_sort_expr.)
         */
        foreach(lc2, pathkey->pk_eclass->ec_members)
        {
            EquivalenceMember *member = (EquivalenceMember *) lfirst(lc2);
            int         indexcol;

            /* No possibility of match if it references other relations */
            if (!bms_equal(member->em_relids, index->rel->relids))
                continue;

            /*
             * We allow any column of the index to match each pathkey; they
             * don't have to match left-to-right as you might expect.  This is
             * correct for GiST, which is the sole existing AM supporting
             * amcanorderbyop.  We might need different logic in future for
             * other implementations.
             */
            for (indexcol = 0; indexcol < index->ncolumns; indexcol++)
            {
                Expr       *expr;

                expr = match_clause_to_ordering_op(index,
                                                   indexcol,
                                                   member->em_expr,
                                                   pathkey->pk_opfamily);
                if (expr)
                {
                    orderby_clauses = lappend(orderby_clauses, expr);
                    clause_columns = lappend_int(clause_columns, indexcol);
                    found = true;
                    break;
                }
            }

            if (found)          /* don't want to look at remaining members */
                break;
        }

        if (!found)             /* fail if no match for this pathkey */
            return;
    }

    *orderby_clauses_p = orderby_clauses;   /* success! */
    *clause_columns_p = clause_columns;
}

match_restriction_clauses_to_index()

static void match_restriction_clauses_to_index ( RelOptInfo *  rel, IndexOptInfo *  index, IndexClauseSet *  clauseset  )

static

Definition at line 2112 of file indxpath.c.

References IndexOptInfo::indrestrictinfo, and match_clauses_to_index().

Referenced by create_index_paths().

{
    /* We can ignore clauses that are implied by the index predicate */
    match_clauses_to_index(index, index->indrestrictinfo, clauseset);
}

match_rowcompare_to_indexcol()

static bool match_rowcompare_to_indexcol ( IndexOptInfo *  index, int  indexcol, Oid  opfamily, Oid  idxcollation, RowCompareExpr *  clause  )

static

Definition at line 2479 of file indxpath.c.

References bms_is_member(), BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, BTLessStrategyNumber, contain_volatile_functions(), get_commutator(), get_op_opfamily_strategy(), IndexCollMatchesExprColl, RowCompareExpr::inputcollids, InvalidOid, RowCompareExpr::largs, linitial, linitial_oid, match_index_to_operand(), RowCompareExpr::opnos, pull_varnos(), RowCompareExpr::rargs, IndexOptInfo::rel, IndexOptInfo::relam, and RelOptInfo::relid.

Referenced by match_clause_to_indexcol().

{
    Index       index_relid = index->rel->relid;
    Node       *leftop,
               *rightop;
    Oid         expr_op;
    Oid         expr_coll;

    /* Forget it if we're not dealing with a btree index */
    if (index->relam != BTREE_AM_OID)
        return false;

    /*
     * We could do the matching on the basis of insisting that the opfamily
     * shown in the RowCompareExpr be the same as the index column's opfamily,
     * but that could fail in the presence of reverse-sort opfamilies: it'd be
     * a matter of chance whether RowCompareExpr had picked the forward or
     * reverse-sort family.  So look only at the operator, and match if it is
     * a member of the index's opfamily (after commutation, if the indexkey is
     * on the right).  We'll worry later about whether any additional
     * operators are matchable to the index.
     */
    leftop = (Node *) linitial(clause->largs);
    rightop = (Node *) linitial(clause->rargs);
    expr_op = linitial_oid(clause->opnos);
    expr_coll = linitial_oid(clause->inputcollids);

    /* Collations must match, if relevant */
    if (!IndexCollMatchesExprColl(idxcollation, expr_coll))
        return false;

    /*
     * These syntactic tests are the same as in match_clause_to_indexcol()
     */
    if (match_index_to_operand(leftop, indexcol, index) &&
        !bms_is_member(index_relid, pull_varnos(rightop)) &&
        !contain_volatile_functions(rightop))
    {
        /* OK, indexkey is on left */
    }
    else if (match_index_to_operand(rightop, indexcol, index) &&
             !bms_is_member(index_relid, pull_varnos(leftop)) &&
             !contain_volatile_functions(leftop))
    {
        /* indexkey is on right, so commute the operator */
        expr_op = get_commutator(expr_op);
        if (expr_op == InvalidOid)
            return false;
    }
    else
        return false;

    /* We're good if the operator is the right type of opfamily member */
    switch (get_op_opfamily_strategy(expr_op, opfamily))
    {
        case BTLessStrategyNumber:
        case BTLessEqualStrategyNumber:
        case BTGreaterEqualStrategyNumber:
        case BTGreaterStrategyNumber:
            return true;
    }

    return false;
}

match_special_index_operator()

static bool match_special_index_operator ( Expr *  clause, Oid  opfamily, Oid  idxcollation, bool  indexkey_on_left  )

static

Definition at line 3376 of file indxpath.c.

References Const::constvalue, DatumGetPointer, get_rightop(), IsA, lc_collate_is_c(), pattern_fixed_prefix(), Pattern_Prefix_Exact, Pattern_Prefix_None, Pattern_Type_Like, Pattern_Type_Like_IC, Pattern_Type_Regex, Pattern_Type_Regex_IC, and pfree().

Referenced by match_clause_to_indexcol().

{
    bool        isIndexable = false;
    Node       *rightop;
    Oid         expr_op;
    Oid         expr_coll;
    Const      *patt;
    Const      *prefix = NULL;
    Pattern_Prefix_Status pstatus = Pattern_Prefix_None;

    /*
     * Currently, all known special operators require the indexkey on the
     * left, but this test could be pushed into the switch statement if some
     * are added that do not...
     */
    if (!indexkey_on_left)
        return false;

    /* we know these will succeed */
    rightop = get_rightop(clause);
    expr_op = ((OpExpr *) clause)->opno;
    expr_coll = ((OpExpr *) clause)->inputcollid;

    /* again, required for all current special ops: */
    if (!IsA(rightop, Const) ||
        ((Const *) rightop)->constisnull)
        return false;
    patt = (Const *) rightop;

    switch (expr_op)
    {
        case OID_TEXT_LIKE_OP:
        case OID_BPCHAR_LIKE_OP:
        case OID_NAME_LIKE_OP:
            /* the right-hand const is type text for all of these */
            pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like, expr_coll,
                                           &prefix, NULL);
            isIndexable = (pstatus != Pattern_Prefix_None);
            break;

        case OID_BYTEA_LIKE_OP:
            pstatus = pattern_fixed_prefix(patt, Pattern_Type_Like, expr_coll,
                                           &prefix, NULL);
            isIndexable = (pstatus != Pattern_Prefix_None);
            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, expr_coll,
                                           &prefix, NULL);
            isIndexable = (pstatus != Pattern_Prefix_None);
            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, expr_coll,
                                           &prefix, NULL);
            isIndexable = (pstatus != Pattern_Prefix_None);
            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, expr_coll,
                                           &prefix, NULL);
            isIndexable = (pstatus != Pattern_Prefix_None);
            break;

        case OID_INET_SUB_OP:
        case OID_INET_SUBEQ_OP:
            isIndexable = true;
            break;
    }

    if (prefix)
    {
        pfree(DatumGetPointer(prefix->constvalue));
        pfree(prefix);
    }

    /* done if the expression doesn't look indexable */
    if (!isIndexable)
        return false;

    /*
     * Must also check that index's opfamily supports the operators we will
     * want to apply.  (A hash index, for example, will not support ">=".)
     * Currently, only btree and spgist support the operators we need.
     *
     * Note: actually, in the Pattern_Prefix_Exact case, we only need "=" so a
     * hash index would work.  Currently it doesn't seem worth checking for
     * that, however.
     *
     * We insist on the opfamily being the specific one we expect, else we'd
     * do the wrong thing if someone were to make a reverse-sort opfamily with
     * the same operators.
     *
     * The non-pattern opclasses will not sort the way we need in most non-C
     * locales.  We can use such an index anyway for an exact match (simple
     * equality), but not for prefix-match cases.  Note that here we are
     * looking at the index's collation, not the expression's collation --
     * this test is *not* dependent on the LIKE/regex operator's collation.
     */
    switch (expr_op)
    {
        case OID_TEXT_LIKE_OP:
        case OID_TEXT_ICLIKE_OP:
        case OID_TEXT_REGEXEQ_OP:
        case OID_TEXT_ICREGEXEQ_OP:
            isIndexable =
                (opfamily == TEXT_PATTERN_BTREE_FAM_OID) ||
                (opfamily == TEXT_SPGIST_FAM_OID) ||
                (opfamily == TEXT_BTREE_FAM_OID &&
                 (pstatus == Pattern_Prefix_Exact ||
                  lc_collate_is_c(idxcollation)));
            break;

        case OID_BPCHAR_LIKE_OP:
        case OID_BPCHAR_ICLIKE_OP:
        case OID_BPCHAR_REGEXEQ_OP:
        case OID_BPCHAR_ICREGEXEQ_OP:
            isIndexable =
                (opfamily == BPCHAR_PATTERN_BTREE_FAM_OID) ||
                (opfamily == BPCHAR_BTREE_FAM_OID &&
                 (pstatus == Pattern_Prefix_Exact ||
                  lc_collate_is_c(idxcollation)));
            break;

        case OID_NAME_LIKE_OP:
        case OID_NAME_ICLIKE_OP:
        case OID_NAME_REGEXEQ_OP:
        case OID_NAME_ICREGEXEQ_OP:
            /* name uses locale-insensitive sorting */
            isIndexable = (opfamily == NAME_BTREE_FAM_OID);
            break;

        case OID_BYTEA_LIKE_OP:
            isIndexable = (opfamily == BYTEA_BTREE_FAM_OID);
            break;

        case OID_INET_SUB_OP:
        case OID_INET_SUBEQ_OP:
            isIndexable = (opfamily == NETWORK_BTREE_FAM_OID);
            break;
    }

    return isIndexable;
}

network_prefix_quals()

static List * network_prefix_quals ( Node *  leftop, Oid  expr_op, Oid  opfamily, Datum  rightop  )

static

Definition at line 4192 of file indxpath.c.

References BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, BTLessEqualStrategyNumber, elog, ERROR, get_opfamily_member(), InvalidOid, lappend(), list_make1, make_opclause(), make_simple_restrictinfo, makeConst(), network_scan_first(), network_scan_last(), and NIL.

Referenced by expand_indexqual_opclause().

{
    bool        is_eq;
    Oid         datatype;
    Oid         opr1oid;
    Oid         opr2oid;
    Datum       opr1right;
    Datum       opr2right;
    List       *result;
    Expr       *expr;

    switch (expr_op)
    {
        case OID_INET_SUB_OP:
            datatype = INETOID;
            is_eq = false;
            break;
        case OID_INET_SUBEQ_OP:
            datatype = INETOID;
            is_eq = true;
            break;
        default:
            elog(ERROR, "unexpected operator: %u", expr_op);
            return NIL;
    }

    /*
     * create clause "key >= network_scan_first( rightop )", or ">" if the
     * operator disallows equality.
     */
    if (is_eq)
    {
        opr1oid = get_opfamily_member(opfamily, datatype, datatype,
                                      BTGreaterEqualStrategyNumber);
        if (opr1oid == InvalidOid)
            elog(ERROR, "no >= operator for opfamily %u", opfamily);
    }
    else
    {
        opr1oid = get_opfamily_member(opfamily, datatype, datatype,
                                      BTGreaterStrategyNumber);
        if (opr1oid == InvalidOid)
            elog(ERROR, "no > operator for opfamily %u", opfamily);
    }

    opr1right = network_scan_first(rightop);

    expr = make_opclause(opr1oid, BOOLOID, false,
                         (Expr *) leftop,
                         (Expr *) makeConst(datatype, -1,
                                            InvalidOid, /* not collatable */
                                            -1, opr1right,
                                            false, false),
                         InvalidOid, InvalidOid);
    result = list_make1(make_simple_restrictinfo(expr));

    /* create clause "key <= network_scan_last( rightop )" */

    opr2oid = get_opfamily_member(opfamily, datatype, datatype,
                                  BTLessEqualStrategyNumber);
    if (opr2oid == InvalidOid)
        elog(ERROR, "no <= operator for opfamily %u", opfamily);

    opr2right = network_scan_last(rightop);

    expr = make_opclause(opr2oid, BOOLOID, false,
                         (Expr *) leftop,
                         (Expr *) makeConst(datatype, -1,
                                            InvalidOid, /* not collatable */
                                            -1, opr2right,
                                            false, false),
                         InvalidOid, InvalidOid);
    result = lappend(result, make_simple_restrictinfo(expr));

    return result;
}

path_usage_comparator()

static int path_usage_comparator ( const void *  a, const void *  b  )

static

Definition at line 1570 of file indxpath.c.

References cost_bitmap_tree_node(), and PathClauseUsage::path.

Referenced by choose_bitmap_and().

{
    PathClauseUsage *pa = *(PathClauseUsage *const *) a;
    PathClauseUsage *pb = *(PathClauseUsage *const *) b;
    Cost        acost;
    Cost        bcost;
    Selectivity aselec;
    Selectivity bselec;

    cost_bitmap_tree_node(pa->path, &acost, &aselec);
    cost_bitmap_tree_node(pb->path, &bcost, &bselec);

    /*
     * If costs are the same, sort by selectivity.
     */
    if (acost < bcost)
        return -1;
    if (acost > bcost)
        return 1;

    if (aselec < bselec)
        return -1;
    if (aselec > bselec)
        return 1;

    return 0;
}

prefix_quals()

static List * prefix_quals ( Node *  leftop, Oid  opfamily, Oid  collation, Const *  prefix, Pattern_Prefix_Status  pstatus  )

static

Definition at line 4066 of file indxpath.c.

References Assert, BTEqualStrategyNumber, BTGreaterEqualStrategyNumber, BTLessStrategyNumber, byteaout(), Const::consttype, Const::constvalue, DatumGetCString, DirectFunctionCall1, elog, ERROR, fmgr_info(), get_opcode(), get_opfamily_member(), InvalidOid, lappend(), list_make1, make_greater_string(), make_opclause(), make_simple_restrictinfo, NIL, Pattern_Prefix_Exact, Pattern_Prefix_None, pfree(), string_to_const(), and TextDatumGetCString.

Referenced by expand_indexqual_opclause().

{
    List       *result;
    Oid         datatype;
    Oid         oproid;
    Expr       *expr;
    FmgrInfo    ltproc;
    Const      *greaterstr;

    Assert(pstatus != Pattern_Prefix_None);

    switch (opfamily)
    {
        case TEXT_BTREE_FAM_OID:
        case TEXT_PATTERN_BTREE_FAM_OID:
        case TEXT_SPGIST_FAM_OID:
            datatype = TEXTOID;
            break;

        case BPCHAR_BTREE_FAM_OID:
        case BPCHAR_PATTERN_BTREE_FAM_OID:
            datatype = BPCHAROID;
            break;

        case NAME_BTREE_FAM_OID:
            datatype = NAMEOID;
            break;

        case BYTEA_BTREE_FAM_OID:
            datatype = BYTEAOID;
            break;

        default:
            /* shouldn't get here */
            elog(ERROR, "unexpected opfamily: %u", opfamily);
            return NIL;
    }

    /*
     * 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 = TextDatumGetCString(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 = get_opfamily_member(opfamily, datatype, datatype,
                                     BTEqualStrategyNumber);
        if (oproid == InvalidOid)
            elog(ERROR, "no = operator for opfamily %u", opfamily);
        expr = make_opclause(oproid, BOOLOID, false,
                             (Expr *) leftop, (Expr *) prefix_const,
                             InvalidOid, collation);
        result = list_make1(make_simple_restrictinfo(expr));
        return result;
    }

    /*
     * Otherwise, we have a nonempty required prefix of the values.
     *
     * We can always say "x >= prefix".
     */
    oproid = get_opfamily_member(opfamily, datatype, datatype,
                                 BTGreaterEqualStrategyNumber);
    if (oproid == InvalidOid)
        elog(ERROR, "no >= operator for opfamily %u", opfamily);
    expr = make_opclause(oproid, BOOLOID, false,
                         (Expr *) leftop, (Expr *) prefix_const,
                         InvalidOid, collation);
    result = list_make1(make_simple_restrictinfo(expr));

    /*-------
     * If we can create a string larger than the prefix, we can say
     * "x < greaterstr".  NB: we rely on make_greater_string() to generate
     * a guaranteed-greater string, not just a probably-greater string.
     * In general this is only guaranteed in C locale, so we'd better be
     * using a C-locale index collation.
     *-------
     */
    oproid = get_opfamily_member(opfamily, datatype, datatype,
                                 BTLessStrategyNumber);
    if (oproid == InvalidOid)
        elog(ERROR, "no < operator for opfamily %u", opfamily);
    fmgr_info(get_opcode(oproid), &ltproc);
    greaterstr = make_greater_string(prefix_const, &ltproc, collation);
    if (greaterstr)
    {
        expr = make_opclause(oproid, BOOLOID, false,
                             (Expr *) leftop, (Expr *) greaterstr,
                             InvalidOid, collation);
        result = lappend(result, make_simple_restrictinfo(expr));
    }

    return result;
}

relation_has_unique_index_for()

bool relation_has_unique_index_for	(	PlannerInfo *	root,
		RelOptInfo *	rel,
		List *	restrictlist,
		List *	exprlist,
		List *	oprlist
	)

Definition at line 2986 of file indxpath.c.

References Assert, RelOptInfo::baserestrictinfo, bms_is_empty(), RestrictInfo::clause, forboth, get_leftop(), get_rightop(), IndexOptInfo::immediate, RelOptInfo::indexlist, IndexOptInfo::indpred, lappend(), RestrictInfo::left_relids, lfirst, lfirst_oid, list_length(), list_member_oid(), match_index_to_operand(), RestrictInfo::mergeopfamilies, IndexOptInfo::ncolumns, NIL, op_in_opfamily(), IndexOptInfo::opfamily, RestrictInfo::outer_is_left, IndexOptInfo::predOK, RestrictInfo::right_relids, and IndexOptInfo::unique.

Referenced by create_unique_path(), and rel_is_distinct_for().

{
    ListCell   *ic;

    Assert(list_length(exprlist) == list_length(oprlist));

    /* Short-circuit if no indexes... */
    if (rel->indexlist == NIL)
        return false;

    /*
     * Examine the rel's restriction clauses for usable var = const clauses
     * that we can add to the restrictlist.
     */
    foreach(ic, rel->baserestrictinfo)
    {
        RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(ic);

        /*
         * Note: can_join won't be set for a restriction clause, but
         * mergeopfamilies will be if it has a mergejoinable operator and
         * doesn't contain volatile functions.
         */
        if (restrictinfo->mergeopfamilies == NIL)
            continue;           /* not mergejoinable */

        /*
         * The clause certainly doesn't refer to anything but the given rel.
         * If either side is pseudoconstant then we can use it.
         */
        if (bms_is_empty(restrictinfo->left_relids))
        {
            /* righthand side is inner */
            restrictinfo->outer_is_left = true;
        }
        else if (bms_is_empty(restrictinfo->right_relids))
        {
            /* lefthand side is inner */
            restrictinfo->outer_is_left = false;
        }
        else
            continue;

        /* OK, add to list */
        restrictlist = lappend(restrictlist, restrictinfo);
    }

    /* Short-circuit the easy case */
    if (restrictlist == NIL && exprlist == NIL)
        return false;

    /* Examine each index of the relation ... */
    foreach(ic, rel->indexlist)
    {
        IndexOptInfo *ind = (IndexOptInfo *) lfirst(ic);
        int         c;

        /*
         * If the index is not unique, or not immediately enforced, or if it's
         * a partial index that doesn't match the query, it's useless here.
         */
        if (!ind->unique || !ind->immediate ||
            (ind->indpred != NIL && !ind->predOK))
            continue;

        /*
         * Try to find each index column in the lists of conditions.  This is
         * O(N^2) or worse, but we expect all the lists to be short.
         */
        for (c = 0; c < ind->ncolumns; c++)
        {
            bool        matched = false;
            ListCell   *lc;
            ListCell   *lc2;

            foreach(lc, restrictlist)
            {
                RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
                Node       *rexpr;

                /*
                 * The condition's equality operator must be a member of the
                 * index opfamily, else it is not asserting the right kind of
                 * equality behavior for this index.  We check this first
                 * since it's probably cheaper than match_index_to_operand().
                 */
                if (!list_member_oid(rinfo->mergeopfamilies, ind->opfamily[c]))
                    continue;

                /*
                 * XXX at some point we may need to check collations here too.
                 * For the moment we assume all collations reduce to the same
                 * notion of equality.
                 */

                /* OK, see if the condition operand matches the index key */
                if (rinfo->outer_is_left)
                    rexpr = get_rightop(rinfo->clause);
                else
                    rexpr = get_leftop(rinfo->clause);

                if (match_index_to_operand(rexpr, c, ind))
                {
                    matched = true; /* column is unique */
                    break;
                }
            }

            if (matched)
                continue;

            forboth(lc, exprlist, lc2, oprlist)
            {
                Node       *expr = (Node *) lfirst(lc);
                Oid         opr = lfirst_oid(lc2);

                /* See if the expression matches the index key */
                if (!match_index_to_operand(expr, c, ind))
                    continue;

                /*
                 * The equality operator must be a member of the index
                 * opfamily, else it is not asserting the right kind of
                 * equality behavior for this index.  We assume the caller
                 * determined it is an equality operator, so we don't need to
                 * check any more tightly than this.
                 */
                if (!op_in_opfamily(opr, ind->opfamily[c]))
                    continue;

                /*
                 * XXX at some point we may need to check collations here too.
                 * For the moment we assume all collations reduce to the same
                 * notion of equality.
                 */

                matched = true; /* column is unique */
                break;
            }

            if (!matched)
                break;          /* no match; this index doesn't help us */
        }

        /* Matched all columns of this index? */
        if (c == ind->ncolumns)
            return true;
    }

    return false;
}

string_to_const()

static Const * string_to_const ( const char *  str, Oid  datatype  )

static

Definition at line 4297 of file indxpath.c.

References elog, ERROR, InvalidOid, makeConst(), NAMEDATALEN, and string_to_datum().

Referenced by prefix_quals().

{
    Datum       conval = string_to_datum(str, datatype);
    Oid         collation;
    int         constlen;

    /*
     * We only need to support a few datatypes here, so hard-wire properties
     * instead of incurring the expense of catalog lookups.
     */
    switch (datatype)
    {
        case TEXTOID:
        case VARCHAROID:
        case BPCHAROID:
            collation = DEFAULT_COLLATION_OID;
            constlen = -1;
            break;

        case NAMEOID:
            collation = InvalidOid;
            constlen = NAMEDATALEN;
            break;

        case BYTEAOID:
            collation = InvalidOid;
            constlen = -1;
            break;

        default:
            elog(ERROR, "unexpected datatype in string_to_const: %u",
                 datatype);
            return NULL;
    }

    return makeConst(datatype, -1, collation, constlen,
                     conval, false, false);
}

string_to_datum()

static Datum string_to_datum ( const char *  str, Oid  datatype  )

static

Definition at line 4279 of file indxpath.c.

References byteain(), CStringGetDatum, CStringGetTextDatum, DirectFunctionCall1, and namein().

Referenced by string_to_const().

{
    /*
     * We cheat a little by assuming that CStringGetTextDatum() will do for
     * bpchar and varchar constants too...
     */
    if (datatype == NAMEOID)
        return DirectFunctionCall1(namein, CStringGetDatum(str));
    else if (datatype == BYTEAOID)
        return DirectFunctionCall1(byteain, CStringGetDatum(str));
    else
        return CStringGetTextDatum(str);
}