src/include/optimizer/paths.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * paths.h
   4  *        prototypes for various files in optimizer/path
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * src/include/optimizer/paths.h
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef PATHS_H
  15 #define PATHS_H
  16
  17 #include "nodes/pathnodes.h"
  18
  19
  20 /*
  21  * allpaths.c
  22  */
  23 extern PGDLLIMPORT bool enable_geqo;
  24 extern PGDLLIMPORT int geqo_threshold;
  25 extern PGDLLIMPORT int min_parallel_table_scan_size;
  26 extern PGDLLIMPORT int min_parallel_index_scan_size;
  27 extern PGDLLIMPORT bool enable_group_by_reordering;
  28
  29 /* Hook for plugins to get control in set_rel_pathlist() */
  30 typedef void (*set_rel_pathlist_hook_type) (PlannerInfo *root,
  31                                                                                         RelOptInfo *rel,
  32                                                                                         Index rti,
  33                                                                                         RangeTblEntry *rte);
  34 extern PGDLLIMPORT set_rel_pathlist_hook_type set_rel_pathlist_hook;
  35
  36 /* Hook for plugins to get control in add_paths_to_joinrel() */
  37 typedef void (*set_join_pathlist_hook_type) (PlannerInfo *root,
  38                                                                                          RelOptInfo *joinrel,
  39                                                                                          RelOptInfo *outerrel,
  40                                                                                          RelOptInfo *innerrel,
  41                                                                                          JoinType jointype,
  42                                                                                          JoinPathExtraData *extra);
  43 extern PGDLLIMPORT set_join_pathlist_hook_type set_join_pathlist_hook;
  44
  45 /* Hook for plugins to replace standard_join_search() */
  46 typedef RelOptInfo *(*join_search_hook_type) (PlannerInfo *root,
  47                                                                                           int levels_needed,
  48                                                                                           List *initial_rels);
  49 extern PGDLLIMPORT join_search_hook_type join_search_hook;
  50
  51
  52 extern RelOptInfo *make_one_rel(PlannerInfo *root, List *joinlist);
  53 extern RelOptInfo *standard_join_search(PlannerInfo *root, int levels_needed,
  54                                                                                 List *initial_rels);
  55
  56 extern void generate_gather_paths(PlannerInfo *root, RelOptInfo *rel,
  57                                                                   bool override_rows);
  58 extern void generate_useful_gather_paths(PlannerInfo *root, RelOptInfo *rel,
  59                                                                                  bool override_rows);
  60 extern int      compute_parallel_worker(RelOptInfo *rel, double heap_pages,
  61                                                                         double index_pages, int max_workers);
  62 extern void create_partial_bitmap_paths(PlannerInfo *root, RelOptInfo *rel,
  63                                                                                 Path *bitmapqual);
  64 extern void generate_partitionwise_join_paths(PlannerInfo *root,
  65                                                                                           RelOptInfo *rel);
  66
  67 /*
  68  * indxpath.c
  69  *        routines to generate index paths
  70  */
  71 extern void create_index_paths(PlannerInfo *root, RelOptInfo *rel);
  72 extern bool relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel,
  73                                                                                   List *restrictlist,
  74                                                                                   List *exprlist, List *oprlist);
  75 extern bool indexcol_is_bool_constant_for_query(PlannerInfo *root,
  76                                                                                                 IndexOptInfo *index,
  77                                                                                                 int indexcol);
  78 extern bool match_index_to_operand(Node *operand, int indexcol,
  79                                                                    IndexOptInfo *index);
  80 extern void check_index_predicates(PlannerInfo *root, RelOptInfo *rel);
  81
  82 /*
  83  * tidpath.c
  84  *        routines to generate tid paths
  85  */
  86 extern void create_tidscan_paths(PlannerInfo *root, RelOptInfo *rel);
  87
  88 /*
  89  * joinpath.c
  90  *         routines to create join paths
  91  */
  92 extern void add_paths_to_joinrel(PlannerInfo *root, RelOptInfo *joinrel,
  93                                                                  RelOptInfo *outerrel, RelOptInfo *innerrel,
  94                                                                  JoinType jointype, SpecialJoinInfo *sjinfo,
  95                                                                  List *restrictlist);
  96
  97 /*
  98  * joinrels.c
  99  *        routines to determine which relations to join
 100  */
 101 extern void join_search_one_level(PlannerInfo *root, int level);
 102 extern RelOptInfo *make_join_rel(PlannerInfo *root,
 103                                                                  RelOptInfo *rel1, RelOptInfo *rel2);
 104 extern Relids add_outer_joins_to_relids(PlannerInfo *root, Relids input_relids,
 105                                                                                 SpecialJoinInfo *sjinfo,
 106                                                                                 List **pushed_down_joins);
 107 extern bool have_join_order_restriction(PlannerInfo *root,
 108                                                                                 RelOptInfo *rel1, RelOptInfo *rel2);
 109 extern bool have_dangerous_phv(PlannerInfo *root,
 110                                                            Relids outer_relids, Relids inner_params);
 111 extern void mark_dummy_rel(RelOptInfo *rel);
 112 extern void init_dummy_sjinfo(SpecialJoinInfo *sjinfo, Relids left_relids,
 113                                                           Relids right_relids);
 114
 115 /*
 116  * equivclass.c
 117  *        routines for managing EquivalenceClasses
 118  */
 119 typedef bool (*ec_matches_callback_type) (PlannerInfo *root,
 120                                                                                   RelOptInfo *rel,
 121                                                                                   EquivalenceClass *ec,
 122                                                                                   EquivalenceMember *em,
 123                                                                                   void *arg);
 124
 125 extern bool process_equivalence(PlannerInfo *root,
 126                                                                 RestrictInfo **p_restrictinfo,
 127                                                                 JoinDomain *jdomain);
 128 extern Expr *canonicalize_ec_expression(Expr *expr,
 129                                                                                 Oid req_type, Oid req_collation);
 130 extern void reconsider_outer_join_clauses(PlannerInfo *root);
 131 extern EquivalenceClass *get_eclass_for_sort_expr(PlannerInfo *root,
 132                                                                                                   Expr *expr,
 133                                                                                                   List *opfamilies,
 134                                                                                                   Oid opcintype,
 135                                                                                                   Oid collation,
 136                                                                                                   Index sortref,
 137                                                                                                   Relids rel,
 138                                                                                                   bool create_it);
 139 extern EquivalenceMember *find_ec_member_matching_expr(EquivalenceClass *ec,
 140                                                                                                            Expr *expr,
 141                                                                                                            Relids relids);
 142 extern EquivalenceMember *find_computable_ec_member(PlannerInfo *root,
 143                                                                                                         EquivalenceClass *ec,
 144                                                                                                         List *exprs,
 145                                                                                                         Relids relids,
 146                                                                                                         bool require_parallel_safe);
 147 extern bool relation_can_be_sorted_early(PlannerInfo *root, RelOptInfo *rel,
 148                                                                                  EquivalenceClass *ec,
 149                                                                                  bool require_parallel_safe);
 150 extern void generate_base_implied_equalities(PlannerInfo *root);
 151 extern List *generate_join_implied_equalities(PlannerInfo *root,
 152                                                                                           Relids join_relids,
 153                                                                                           Relids outer_relids,
 154                                                                                           RelOptInfo *inner_rel,
 155                                                                                           SpecialJoinInfo *sjinfo);
 156 extern List *generate_join_implied_equalities_for_ecs(PlannerInfo *root,
 157                                                                                                           List *eclasses,
 158                                                                                                           Relids join_relids,
 159                                                                                                           Relids outer_relids,
 160                                                                                                           RelOptInfo *inner_rel);
 161 extern bool exprs_known_equal(PlannerInfo *root, Node *item1, Node *item2);
 162 extern EquivalenceClass *match_eclasses_to_foreign_key_col(PlannerInfo *root,
 163                                                                                                                    ForeignKeyOptInfo *fkinfo,
 164                                                                                                                    int colno);
 165 extern RestrictInfo *find_derived_clause_for_ec_member(EquivalenceClass *ec,
 166                                                                                                            EquivalenceMember *em);
 167 extern void add_child_rel_equivalences(PlannerInfo *root,
 168                                                                            AppendRelInfo *appinfo,
 169                                                                            RelOptInfo *parent_rel,
 170                                                                            RelOptInfo *child_rel);
 171 extern void add_child_join_rel_equivalences(PlannerInfo *root,
 172                                                                                         int nappinfos,
 173                                                                                         AppendRelInfo **appinfos,
 174                                                                                         RelOptInfo *parent_joinrel,
 175                                                                                         RelOptInfo *child_joinrel);
 176 extern List *generate_implied_equalities_for_column(PlannerInfo *root,
 177                                                                                                         RelOptInfo *rel,
 178                                                                                                         ec_matches_callback_type callback,
 179                                                                                                         void *callback_arg,
 180                                                                                                         Relids prohibited_rels);
 181 extern bool have_relevant_eclass_joinclause(PlannerInfo *root,
 182                                                                                         RelOptInfo *rel1, RelOptInfo *rel2);
 183 extern bool has_relevant_eclass_joinclause(PlannerInfo *root,
 184                                                                                    RelOptInfo *rel1);
 185 extern bool eclass_useful_for_merging(PlannerInfo *root,
 186                                                                           EquivalenceClass *eclass,
 187                                                                           RelOptInfo *rel);
 188 extern bool is_redundant_derived_clause(RestrictInfo *rinfo, List *clauselist);
 189 extern bool is_redundant_with_indexclauses(RestrictInfo *rinfo,
 190                                                                                    List *indexclauses);
 191
 192 /*
 193  * pathkeys.c
 194  *        utilities for matching and building path keys
 195  */
 196 typedef enum
 197 {
 198         PATHKEYS_EQUAL,                         /* pathkeys are identical */
 199         PATHKEYS_BETTER1,                       /* pathkey 1 is a superset of pathkey 2 */
 200         PATHKEYS_BETTER2,                       /* vice versa */
 201         PATHKEYS_DIFFERENT,                     /* neither pathkey includes the other */
 202 } PathKeysComparison;
 203
 204 extern PathKeysComparison compare_pathkeys(List *keys1, List *keys2);
 205 extern bool pathkeys_contained_in(List *keys1, List *keys2);
 206 extern bool pathkeys_count_contained_in(List *keys1, List *keys2, int *n_common);
 207 extern List *get_useful_group_keys_orderings(PlannerInfo *root, Path *path);
 208 extern Path *get_cheapest_path_for_pathkeys(List *paths, List *pathkeys,
 209                                                                                         Relids required_outer,
 210                                                                                         CostSelector cost_criterion,
 211                                                                                         bool require_parallel_safe);
 212 extern Path *get_cheapest_fractional_path_for_pathkeys(List *paths,
 213                                                                                                            List *pathkeys,
 214                                                                                                            Relids required_outer,
 215                                                                                                            double fraction);
 216 extern Path *get_cheapest_parallel_safe_total_inner(List *paths);
 217 extern List *build_index_pathkeys(PlannerInfo *root, IndexOptInfo *index,
 218                                                                   ScanDirection scandir);
 219 extern List *build_partition_pathkeys(PlannerInfo *root, RelOptInfo *partrel,
 220                                                                           ScanDirection scandir, bool *partialkeys);
 221 extern List *build_expression_pathkey(PlannerInfo *root, Expr *expr,
 222                                                                           Oid opno,
 223                                                                           Relids rel, bool create_it);
 224 extern List *convert_subquery_pathkeys(PlannerInfo *root, RelOptInfo *rel,
 225                                                                            List *subquery_pathkeys,
 226                                                                            List *subquery_tlist);
 227 extern List *build_join_pathkeys(PlannerInfo *root,
 228                                                                  RelOptInfo *joinrel,
 229                                                                  JoinType jointype,
 230                                                                  List *outer_pathkeys);
 231 extern List *make_pathkeys_for_sortclauses(PlannerInfo *root,
 232                                                                                    List *sortclauses,
 233                                                                                    List *tlist);
 234 extern List *make_pathkeys_for_sortclauses_extended(PlannerInfo *root,
 235                                                                                                         List **sortclauses,
 236                                                                                                         List *tlist,
 237                                                                                                         bool remove_redundant,
 238                                                                                                         bool *sortable);
 239 extern void initialize_mergeclause_eclasses(PlannerInfo *root,
 240                                                                                         RestrictInfo *restrictinfo);
 241 extern void update_mergeclause_eclasses(PlannerInfo *root,
 242                                                                                 RestrictInfo *restrictinfo);
 243 extern List *find_mergeclauses_for_outer_pathkeys(PlannerInfo *root,
 244                                                                                                   List *pathkeys,
 245                                                                                                   List *restrictinfos);
 246 extern List *select_outer_pathkeys_for_merge(PlannerInfo *root,
 247                                                                                          List *mergeclauses,
 248                                                                                          RelOptInfo *joinrel);
 249 extern List *make_inner_pathkeys_for_merge(PlannerInfo *root,
 250                                                                                    List *mergeclauses,
 251                                                                                    List *outer_pathkeys);
 252 extern List *trim_mergeclauses_for_inner_pathkeys(PlannerInfo *root,
 253                                                                                                   List *mergeclauses,
 254                                                                                                   List *pathkeys);
 255 extern List *truncate_useless_pathkeys(PlannerInfo *root,
 256                                                                            RelOptInfo *rel,
 257                                                                            List *pathkeys);
 258 extern bool has_useful_pathkeys(PlannerInfo *root, RelOptInfo *rel);
 259 extern List *append_pathkeys(List *target, List *source);
 260 extern PathKey *make_canonical_pathkey(PlannerInfo *root,
 261                                                                            EquivalenceClass *eclass, Oid opfamily,
 262                                                                            int strategy, bool nulls_first);
 263 extern void add_paths_to_append_rel(PlannerInfo *root, RelOptInfo *rel,
 264                                                                         List *live_childrels);
 265
 266 #endif                                                  /* PATHS_H */