granicus.if.org Git - postgresql/blob - src/include/optimizer/paths.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * paths.h
   4  *        prototypes for various files in optimizer/path (were separate
   5  *        header files)
   6  *
   7  *
   8  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
   9  * Portions Copyright (c) 1994, Regents of the University of California
  10  *
  11  * $Id: paths.h,v 1.47 2000/09/12 21:07:11 tgl Exp $
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15 #ifndef PATHS_H
  16 #define PATHS_H
  17
  18 #include "nodes/relation.h"
  19
  20 /* default GEQO threshold (default value for geqo_rels) */
  21 #define DEFAULT_GEQO_RELS 11
  22
  23
  24 /*
  25  * allpaths.c
  26  */
  27 extern bool enable_geqo;
  28 extern int      geqo_rels;
  29
  30 extern RelOptInfo *make_one_rel(Query *root);
  31
  32 /*
  33  * indxpath.c
  34  *        routines to generate index paths
  35  */
  36 extern void create_index_paths(Query *root, RelOptInfo *rel, List *indices,
  37                                    List *restrictinfo_list,
  38                                    List *joininfo_list);
  39 extern Oid indexable_operator(Expr *clause, Oid opclass, Oid relam,
  40                                    bool indexkey_on_left);
  41 extern List *extract_or_indexqual_conditions(RelOptInfo *rel,
  42                                                                 IndexOptInfo *index,
  43                                                                 Expr *orsubclause);
  44 extern List *expand_indexqual_conditions(List *indexquals);
  45
  46 /*
  47  * orindxpath.c
  48  *        additional routines for indexable OR clauses
  49  */
  50 extern void create_or_index_paths(Query *root, RelOptInfo *rel,
  51                                           List *clauses);
  52
  53 /*
  54  * tidpath.h
  55  *        routines to generate tid paths
  56  */
  57 extern void create_tidscan_paths(Query *root, RelOptInfo *rel);
  58
  59 /*
  60  * joinpath.c
  61  *         routines to create join paths
  62  */
  63 extern void add_paths_to_joinrel(Query *root, RelOptInfo *joinrel,
  64                                                                  RelOptInfo *outerrel,
  65                                                                  RelOptInfo *innerrel,
  66                                                                  JoinType jointype,
  67                                                                  List *restrictlist);
  68
  69 /*
  70  * joinrels.c
  71  *        routines to determine which relations to join
  72  */
  73 extern List *make_rels_by_joins(Query *root, int level, List **joinrels);
  74 extern List *make_rels_by_clause_joins(Query *root,
  75                                                                            RelOptInfo *old_rel,
  76                                                                            List *other_rels);
  77 extern List *make_rels_by_clauseless_joins(Query *root,
  78                                                                                    RelOptInfo *old_rel,
  79                                                                                    List *other_rels);
  80 extern RelOptInfo *make_rel_from_jointree(Query *root, Node *jtnode);
  81
  82 /*
  83  * pathkeys.c
  84  *        utilities for matching and building path keys
  85  */
  86 typedef enum
  87 {
  88         PATHKEYS_EQUAL,                         /* pathkeys are identical */
  89         PATHKEYS_BETTER1,                       /* pathkey 1 is a superset of pathkey 2 */
  90         PATHKEYS_BETTER2,                       /* vice versa */
  91         PATHKEYS_DIFFERENT                      /* neither pathkey includes the other */
  92 } PathKeysComparison;
  93
  94 extern void add_equijoined_keys(Query *root, RestrictInfo *restrictinfo);
  95 extern void generate_implied_equalities(Query *root);
  96 extern List *canonicalize_pathkeys(Query *root, List *pathkeys);
  97 extern PathKeysComparison compare_pathkeys(List *keys1, List *keys2);
  98 extern bool pathkeys_contained_in(List *keys1, List *keys2);
  99 extern Path *get_cheapest_path_for_pathkeys(List *paths, List *pathkeys,
 100                                                            CostSelector cost_criterion);
 101 extern Path *get_cheapest_fractional_path_for_pathkeys(List *paths,
 102                                                                                   List *pathkeys,
 103                                                                                   double fraction);
 104 extern List *build_index_pathkeys(Query *root, RelOptInfo *rel,
 105                                          IndexOptInfo *index,
 106                                          ScanDirection scandir);
 107 extern List *build_join_pathkeys(List *outer_pathkeys,
 108                                         List *join_rel_tlist,
 109                                         List *equi_key_list);
 110 extern List *make_pathkeys_for_sortclauses(List *sortclauses,
 111                                                           List *tlist);
 112 extern List *find_mergeclauses_for_pathkeys(List *pathkeys,
 113                                                            List *restrictinfos);
 114 extern List *make_pathkeys_for_mergeclauses(Query *root,
 115                                                                                         List *mergeclauses,
 116                                                                                         RelOptInfo *rel);
 117
 118 #endif   /* PATHS_H */