SSL paths.h

/*-------------------------------------------------------------------------
 *
 * paths.h
 *   prototypes for various files in optimizer/path
 *
 *
 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/optimizer/paths.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef PATHS_H
#define PATHS_H

#include "nodes/pathnodes.h"


/*
 * allpaths.c
 */
extern PGDLLIMPORT bool enable_geqo;
extern PGDLLIMPORT int geqo_threshold;
extern PGDLLIMPORT int min_parallel_table_scan_size;
extern PGDLLIMPORT int min_parallel_index_scan_size;
extern PGDLLIMPORT bool enable_group_by_reordering;

/* Hook for plugins to get control in set_rel_pathlist() */
typedef void (*set_rel_pathlist_hook_type) (PlannerInfo *root,
           RelOptInfo *rel,
           Index rti,
           RangeTblEntry *rte);
extern PGDLLIMPORT set_rel_pathlist_hook_type set_rel_pathlist_hook;

/* Hook for plugins to get control in add_paths_to_joinrel() */
typedef void (*set_join_pathlist_hook_type) (PlannerInfo *root,
            RelOptInfo *joinrel,
            RelOptInfo *outerrel,
            RelOptInfo *innerrel,
            JoinType jointype,
            JoinPathExtraData *extra);
extern PGDLLIMPORT set_join_pathlist_hook_type set_join_pathlist_hook;

/* Hook for plugins to replace standard_join_search() */
typedef RelOptInfo *(*join_search_hook_type) (PlannerInfo *root,
             int levels_needed,
             List *initial_rels);
extern PGDLLIMPORT join_search_hook_type join_search_hook;


extern RelOptInfo *make_one_rel(PlannerInfo *root, List *joinlist);
extern RelOptInfo *standard_join_search(PlannerInfo *root, int levels_needed,
          List *initial_rels);

extern void generate_gather_paths(PlannerInfo *root, RelOptInfo *rel,
          bool override_rows);
extern void generate_useful_gather_paths(PlannerInfo *root, RelOptInfo *rel,
           bool override_rows);
extern int compute_parallel_worker(RelOptInfo *rel, double heap_pages,
         double index_pages, int max_workers);
extern void create_partial_bitmap_paths(PlannerInfo *root, RelOptInfo *rel,
          Path *bitmapqual);
extern void generate_partitionwise_join_paths(PlannerInfo *root,
             RelOptInfo *rel);

/*
 * indxpath.c
 *   routines to generate index paths
 */
extern void create_index_paths(PlannerInfo *root, RelOptInfo *rel);
extern bool relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel,
            List *restrictlist,
            List *exprlist, List *oprlist);
extern bool relation_has_unique_index_ext(PlannerInfo *root, RelOptInfo *rel,
            List *restrictlist, List *exprlist,
            List *oprlist, List **extra_clauses);
extern bool indexcol_is_bool_constant_for_query(PlannerInfo *root,
            IndexOptInfo *index,
            int indexcol);
extern bool match_index_to_operand(Node *operand, int indexcol,
           IndexOptInfo *index);
extern Node *strip_phvs_in_index_operand(Node *operand);
extern void check_index_predicates(PlannerInfo *root, RelOptInfo *rel);

/*
 * tidpath.c
 *   routines to generate tid paths
 */
extern bool create_tidscan_paths(PlannerInfo *root, RelOptInfo *rel);

/*
 * joinpath.c
 *    routines to create join paths
 */
extern void add_paths_to_joinrel(PlannerInfo *root, RelOptInfo *joinrel,
         RelOptInfo *outerrel, RelOptInfo *innerrel,
         JoinType jointype, SpecialJoinInfo *sjinfo,
         List *restrictlist);

/*
 * joinrels.c
 *   routines to determine which relations to join
 */
extern void join_search_one_level(PlannerInfo *root, int level);
extern RelOptInfo *make_join_rel(PlannerInfo *root,
         RelOptInfo *rel1, RelOptInfo *rel2);
extern Relids add_outer_joins_to_relids(PlannerInfo *root, Relids input_relids,
          SpecialJoinInfo *sjinfo,
          List **pushed_down_joins);
extern bool have_join_order_restriction(PlannerInfo *root,
          RelOptInfo *rel1, RelOptInfo *rel2);
extern void mark_dummy_rel(RelOptInfo *rel);
extern void init_dummy_sjinfo(SpecialJoinInfo *sjinfo, Relids left_relids,
         Relids right_relids);

/*
 * equivclass.c
 *   routines for managing EquivalenceClasses
 */
typedef bool (*ec_matches_callback_type) (PlannerInfo *root,
            RelOptInfo *rel,
            EquivalenceClass *ec,
            EquivalenceMember *em,
            void *arg);

extern bool process_equivalence(PlannerInfo *root,
        RestrictInfo **p_restrictinfo,
        JoinDomain *jdomain);
extern Expr *canonicalize_ec_expression(Expr *expr,
          Oid req_type, Oid req_collation);
extern void reconsider_outer_join_clauses(PlannerInfo *root);
extern void rebuild_eclass_attr_needed(PlannerInfo *root);
extern EquivalenceClass *get_eclass_for_sort_expr(PlannerInfo *root,
              Expr *expr,
              List *opfamilies,
              Oid opcintype,
              Oid collation,
              Index sortref,
              Relids rel,
              bool create_it);
extern EquivalenceMember *find_ec_member_matching_expr(EquivalenceClass *ec,
                Expr *expr,
                Relids relids);
extern EquivalenceMember *find_computable_ec_member(PlannerInfo *root,
             EquivalenceClass *ec,
             List *exprs,
             Relids relids,
             bool require_parallel_safe);
extern bool relation_can_be_sorted_early(PlannerInfo *root, RelOptInfo *rel,
           EquivalenceClass *ec,
           bool require_parallel_safe);
extern void generate_base_implied_equalities(PlannerInfo *root);
extern List *generate_join_implied_equalities(PlannerInfo *root,
             Relids join_relids,
             Relids outer_relids,
             RelOptInfo *inner_rel,
             SpecialJoinInfo *sjinfo);
extern List *generate_join_implied_equalities_for_ecs(PlannerInfo *root,
               List *eclasses,
               Relids join_relids,
               Relids outer_relids,
               RelOptInfo *inner_rel);
extern bool exprs_known_equal(PlannerInfo *root, Node *item1, Node *item2,
         Oid opfamily);
extern EquivalenceClass *match_eclasses_to_foreign_key_col(PlannerInfo *root,
                 ForeignKeyOptInfo *fkinfo,
                 int colno);
extern RestrictInfo *find_derived_clause_for_ec_member(PlannerInfo *root,
                EquivalenceClass *ec,
                EquivalenceMember *em);
extern void add_child_rel_equivalences(PlannerInfo *root,
            AppendRelInfo *appinfo,
            RelOptInfo *parent_rel,
            RelOptInfo *child_rel);
extern void add_child_join_rel_equivalences(PlannerInfo *root,
           int nappinfos,
           AppendRelInfo **appinfos,
           RelOptInfo *parent_joinrel,
           RelOptInfo *child_joinrel);
extern void add_setop_child_rel_equivalences(PlannerInfo *root,
            RelOptInfo *child_rel,
            List *child_tlist,
            List *setop_pathkeys);
extern void setup_eclass_member_iterator(EquivalenceMemberIterator *it,
           EquivalenceClass *ec,
           Relids child_relids);
extern EquivalenceMember *eclass_member_iterator_next(EquivalenceMemberIterator *it);
extern List *generate_implied_equalities_for_column(PlannerInfo *root,
             RelOptInfo *rel,
             ec_matches_callback_type callback,
             void *callback_arg,
             Relids prohibited_rels);
extern bool have_relevant_eclass_joinclause(PlannerInfo *root,
           RelOptInfo *rel1, RelOptInfo *rel2);
extern bool has_relevant_eclass_joinclause(PlannerInfo *root,
             RelOptInfo *rel1);
extern bool eclass_useful_for_merging(PlannerInfo *root,
           EquivalenceClass *eclass,
           RelOptInfo *rel);
extern bool is_redundant_derived_clause(RestrictInfo *rinfo, List *clauselist);
extern bool is_redundant_with_indexclauses(RestrictInfo *rinfo,
             List *indexclauses);
extern void ec_clear_derived_clauses(EquivalenceClass *ec);

/*
 * pathkeys.c
 *   utilities for matching and building path keys
 */
typedef enum
{
 PATHKEYS_EQUAL,    /* pathkeys are identical */
 PATHKEYS_BETTER1,   /* pathkey 1 is a superset of pathkey 2 */
 PATHKEYS_BETTER2,   /* vice versa */
 PATHKEYS_DIFFERENT,   /* neither pathkey includes the other */
} PathKeysComparison;

extern PathKeysComparison compare_pathkeys(List *keys1, List *keys2);
extern bool pathkeys_contained_in(List *keys1, List *keys2);
extern bool pathkeys_count_contained_in(List *keys1, List *keys2, int *n_common);
extern List *get_useful_group_keys_orderings(PlannerInfo *root, Path *path);
extern Path *get_cheapest_path_for_pathkeys(List *paths, List *pathkeys,
           Relids required_outer,
           CostSelector cost_criterion,
           bool require_parallel_safe);
extern Path *get_cheapest_fractional_path_for_pathkeys(List *paths,
                List *pathkeys,
                Relids required_outer,
                double fraction);
extern Path *get_cheapest_parallel_safe_total_inner(List *paths);
extern List *build_index_pathkeys(PlannerInfo *root, IndexOptInfo *index,
          ScanDirection scandir);
extern List *build_partition_pathkeys(PlannerInfo *root, RelOptInfo *partrel,
           ScanDirection scandir, bool *partialkeys);
extern List *build_expression_pathkey(PlannerInfo *root, Expr *expr,
           Oid opno,
           Relids rel, bool create_it);
extern List *convert_subquery_pathkeys(PlannerInfo *root, RelOptInfo *rel,
            List *subquery_pathkeys,
            List *subquery_tlist);
extern List *build_join_pathkeys(PlannerInfo *root,
         RelOptInfo *joinrel,
         JoinType jointype,
         List *outer_pathkeys);
extern List *make_pathkeys_for_sortclauses(PlannerInfo *root,
             List *sortclauses,
             List *tlist);
extern List *make_pathkeys_for_sortclauses_extended(PlannerInfo *root,
             List **sortclauses,
             List *tlist,
             bool remove_redundant,
             bool remove_group_rtindex,
             bool *sortable,
             bool set_ec_sortref);
extern void initialize_mergeclause_eclasses(PlannerInfo *root,
           RestrictInfo *restrictinfo);
extern void update_mergeclause_eclasses(PlannerInfo *root,
          RestrictInfo *restrictinfo);
extern List *find_mergeclauses_for_outer_pathkeys(PlannerInfo *root,
              List *pathkeys,
              List *restrictinfos);
extern List *select_outer_pathkeys_for_merge(PlannerInfo *root,
            List *mergeclauses,
            RelOptInfo *joinrel);
extern List *make_inner_pathkeys_for_merge(PlannerInfo *root,
             List *mergeclauses,
             List *outer_pathkeys);
extern List *trim_mergeclauses_for_inner_pathkeys(PlannerInfo *root,
              List *mergeclauses,
              List *pathkeys);
extern List *truncate_useless_pathkeys(PlannerInfo *root,
            RelOptInfo *rel,
            List *pathkeys);
extern bool has_useful_pathkeys(PlannerInfo *root, RelOptInfo *rel);
extern List *append_pathkeys(List *target, List *source);
extern PathKey *make_canonical_pathkey(PlannerInfo *root,
            EquivalenceClass *eclass, Oid opfamily,
            CompareType cmptype, bool nulls_first);
extern void add_paths_to_append_rel(PlannerInfo *root, RelOptInfo *rel,
         List *live_childrels);

#endif       /* PATHS_H */