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pathnodes.h
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1 /*-------------------------------------------------------------------------
2  *
3  * pathnodes.h
4  * Definitions for planner's internal data structures, especially Paths.
5  *
6  *
7  * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/include/nodes/pathnodes.h
11  *
12  *-------------------------------------------------------------------------
13  */
14 #ifndef PATHNODES_H
15 #define PATHNODES_H
16 
17 #include "access/sdir.h"
18 #include "lib/stringinfo.h"
19 #include "nodes/params.h"
20 #include "nodes/parsenodes.h"
21 #include "storage/block.h"
22 
23 
24 /*
25  * Relids
26  * Set of relation identifiers (indexes into the rangetable).
27  */
28 typedef Bitmapset *Relids;
29 
30 /*
31  * When looking for a "cheapest path", this enum specifies whether we want
32  * cheapest startup cost or cheapest total cost.
33  */
34 typedef enum CostSelector
35 {
37 } CostSelector;
38 
39 /*
40  * The cost estimate produced by cost_qual_eval() includes both a one-time
41  * (startup) cost, and a per-tuple cost.
42  */
43 typedef struct QualCost
44 {
45  Cost startup; /* one-time cost */
46  Cost per_tuple; /* per-evaluation cost */
47 } QualCost;
48 
49 /*
50  * Costing aggregate function execution requires these statistics about
51  * the aggregates to be executed by a given Agg node. Note that the costs
52  * include the execution costs of the aggregates' argument expressions as
53  * well as the aggregate functions themselves. Also, the fields must be
54  * defined so that initializing the struct to zeroes with memset is correct.
55  */
56 typedef struct AggClauseCosts
57 {
58  int numAggs; /* total number of aggregate functions */
59  int numOrderedAggs; /* number w/ DISTINCT/ORDER BY/WITHIN GROUP */
60  bool hasNonPartial; /* does any agg not support partial mode? */
61  bool hasNonSerial; /* is any partial agg non-serializable? */
62  QualCost transCost; /* total per-input-row execution costs */
63  QualCost finalCost; /* total per-aggregated-row costs */
64  Size transitionSpace; /* space for pass-by-ref transition data */
66 
67 /*
68  * This enum identifies the different types of "upper" (post-scan/join)
69  * relations that we might deal with during planning.
70  */
71 typedef enum UpperRelationKind
72 {
73  UPPERREL_SETOP, /* result of UNION/INTERSECT/EXCEPT, if any */
74  UPPERREL_PARTIAL_GROUP_AGG, /* result of partial grouping/aggregation, if
75  * any */
76  UPPERREL_GROUP_AGG, /* result of grouping/aggregation, if any */
77  UPPERREL_WINDOW, /* result of window functions, if any */
78  UPPERREL_DISTINCT, /* result of "SELECT DISTINCT", if any */
79  UPPERREL_ORDERED, /* result of ORDER BY, if any */
80  UPPERREL_FINAL /* result of any remaining top-level actions */
81  /* NB: UPPERREL_FINAL must be last enum entry; it's used to size arrays */
83 
84 /*
85  * This enum identifies which type of relation is being planned through the
86  * inheritance planner. INHKIND_NONE indicates the inheritance planner
87  * was not used.
88  */
89 typedef enum InheritanceKind
90 {
95 
96 /*----------
97  * PlannerGlobal
98  * Global information for planning/optimization
99  *
100  * PlannerGlobal holds state for an entire planner invocation; this state
101  * is shared across all levels of sub-Queries that exist in the command being
102  * planned.
103  *----------
104  */
105 typedef struct PlannerGlobal
106 {
108 
109  ParamListInfo boundParams; /* Param values provided to planner() */
110 
111  List *subplans; /* Plans for SubPlan nodes */
112 
113  List *subroots; /* PlannerInfos for SubPlan nodes */
114 
115  Bitmapset *rewindPlanIDs; /* indices of subplans that require REWIND */
116 
117  List *finalrtable; /* "flat" rangetable for executor */
118 
119  List *finalrowmarks; /* "flat" list of PlanRowMarks */
120 
121  List *resultRelations; /* "flat" list of integer RT indexes */
122 
123  List *rootResultRelations; /* "flat" list of integer RT indexes */
124 
125  List *appendRelations; /* "flat" list of AppendRelInfos */
126 
127  List *relationOids; /* OIDs of relations the plan depends on */
128 
129  List *invalItems; /* other dependencies, as PlanInvalItems */
130 
131  List *paramExecTypes; /* type OIDs for PARAM_EXEC Params */
132 
133  Index lastPHId; /* highest PlaceHolderVar ID assigned */
134 
135  Index lastRowMarkId; /* highest PlanRowMark ID assigned */
136 
137  int lastPlanNodeId; /* highest plan node ID assigned */
138 
139  bool transientPlan; /* redo plan when TransactionXmin changes? */
140 
141  bool dependsOnRole; /* is plan specific to current role? */
142 
143  bool parallelModeOK; /* parallel mode potentially OK? */
144 
145  bool parallelModeNeeded; /* parallel mode actually required? */
146 
147  char maxParallelHazard; /* worst PROPARALLEL hazard level */
148 
149  PartitionDirectory partition_directory; /* partition descriptors */
150 } PlannerGlobal;
151 
152 /* macro for fetching the Plan associated with a SubPlan node */
153 #define planner_subplan_get_plan(root, subplan) \
154  ((Plan *) list_nth((root)->glob->subplans, (subplan)->plan_id - 1))
155 
156 
157 /*----------
158  * PlannerInfo
159  * Per-query information for planning/optimization
160  *
161  * This struct is conventionally called "root" in all the planner routines.
162  * It holds links to all of the planner's working state, in addition to the
163  * original Query. Note that at present the planner extensively modifies
164  * the passed-in Query data structure; someday that should stop.
165  *
166  * For reasons explained in optimizer/optimizer.h, we define the typedef
167  * either here or in that header, whichever is read first.
168  *----------
169  */
170 #ifndef HAVE_PLANNERINFO_TYPEDEF
171 typedef struct PlannerInfo PlannerInfo;
172 #define HAVE_PLANNERINFO_TYPEDEF 1
173 #endif
174 
176 {
178 
179  Query *parse; /* the Query being planned */
180 
181  PlannerGlobal *glob; /* global info for current planner run */
182 
183  Index query_level; /* 1 at the outermost Query */
184 
185  PlannerInfo *parent_root; /* NULL at outermost Query */
186 
187  /*
188  * plan_params contains the expressions that this query level needs to
189  * make available to a lower query level that is currently being planned.
190  * outer_params contains the paramIds of PARAM_EXEC Params that outer
191  * query levels will make available to this query level.
192  */
193  List *plan_params; /* list of PlannerParamItems, see below */
195 
196  /*
197  * simple_rel_array holds pointers to "base rels" and "other rels" (see
198  * comments for RelOptInfo for more info). It is indexed by rangetable
199  * index (so entry 0 is always wasted). Entries can be NULL when an RTE
200  * does not correspond to a base relation, such as a join RTE or an
201  * unreferenced view RTE; or if the RelOptInfo hasn't been made yet.
202  */
203  struct RelOptInfo **simple_rel_array; /* All 1-rel RelOptInfos */
204  int simple_rel_array_size; /* allocated size of array */
205 
206  /*
207  * simple_rte_array is the same length as simple_rel_array and holds
208  * pointers to the associated rangetable entries. Using this is a shade
209  * faster than using rt_fetch(), mostly due to fewer indirections.
210  */
211  RangeTblEntry **simple_rte_array; /* rangetable as an array */
212 
213  /*
214  * append_rel_array is the same length as the above arrays, and holds
215  * pointers to the corresponding AppendRelInfo entry indexed by
216  * child_relid, or NULL if the rel is not an appendrel child. The array
217  * itself is not allocated if append_rel_list is empty.
218  */
220 
221  /*
222  * all_baserels is a Relids set of all base relids (but not "other"
223  * relids) in the query; that is, the Relids identifier of the final join
224  * we need to form. This is computed in make_one_rel, just before we
225  * start making Paths.
226  */
228 
229  /*
230  * nullable_baserels is a Relids set of base relids that are nullable by
231  * some outer join in the jointree; these are rels that are potentially
232  * nullable below the WHERE clause, SELECT targetlist, etc. This is
233  * computed in deconstruct_jointree.
234  */
236 
237  /*
238  * join_rel_list is a list of all join-relation RelOptInfos we have
239  * considered in this planning run. For small problems we just scan the
240  * list to do lookups, but when there are many join relations we build a
241  * hash table for faster lookups. The hash table is present and valid
242  * when join_rel_hash is not NULL. Note that we still maintain the list
243  * even when using the hash table for lookups; this simplifies life for
244  * GEQO.
245  */
246  List *join_rel_list; /* list of join-relation RelOptInfos */
247  struct HTAB *join_rel_hash; /* optional hashtable for join relations */
248 
249  /*
250  * When doing a dynamic-programming-style join search, join_rel_level[k]
251  * is a list of all join-relation RelOptInfos of level k, and
252  * join_cur_level is the current level. New join-relation RelOptInfos are
253  * automatically added to the join_rel_level[join_cur_level] list.
254  * join_rel_level is NULL if not in use.
255  */
256  List **join_rel_level; /* lists of join-relation RelOptInfos */
257  int join_cur_level; /* index of list being extended */
258 
259  List *init_plans; /* init SubPlans for query */
260 
261  List *cte_plan_ids; /* per-CTE-item list of subplan IDs */
262 
263  List *multiexpr_params; /* List of Lists of Params for MULTIEXPR
264  * subquery outputs */
265 
266  List *eq_classes; /* list of active EquivalenceClasses */
267 
268  bool ec_merging_done; /* set true once ECs are canonical */
269 
270  List *canon_pathkeys; /* list of "canonical" PathKeys */
271 
272  List *left_join_clauses; /* list of RestrictInfos for mergejoinable
273  * outer join clauses w/nonnullable var on
274  * left */
275 
276  List *right_join_clauses; /* list of RestrictInfos for mergejoinable
277  * outer join clauses w/nonnullable var on
278  * right */
279 
280  List *full_join_clauses; /* list of RestrictInfos for mergejoinable
281  * full join clauses */
282 
283  List *join_info_list; /* list of SpecialJoinInfos */
284 
285  /*
286  * Note: for AppendRelInfos describing partitions of a partitioned table,
287  * we guarantee that partitions that come earlier in the partitioned
288  * table's PartitionDesc will appear earlier in append_rel_list.
289  */
290  List *append_rel_list; /* list of AppendRelInfos */
291 
292  List *rowMarks; /* list of PlanRowMarks */
293 
294  List *placeholder_list; /* list of PlaceHolderInfos */
295 
296  List *fkey_list; /* list of ForeignKeyOptInfos */
297 
298  List *query_pathkeys; /* desired pathkeys for query_planner() */
299 
300  List *group_pathkeys; /* groupClause pathkeys, if any */
301  List *window_pathkeys; /* pathkeys of bottom window, if any */
302  List *distinct_pathkeys; /* distinctClause pathkeys, if any */
303  List *sort_pathkeys; /* sortClause pathkeys, if any */
304 
305  List *part_schemes; /* Canonicalised partition schemes used in the
306  * query. */
307 
308  List *initial_rels; /* RelOptInfos we are now trying to join */
309 
310  /* Use fetch_upper_rel() to get any particular upper rel */
311  List *upper_rels[UPPERREL_FINAL + 1]; /* upper-rel RelOptInfos */
312 
313  /* Result tlists chosen by grouping_planner for upper-stage processing */
314  struct PathTarget *upper_targets[UPPERREL_FINAL + 1];
315 
316  /*
317  * The fully-processed targetlist is kept here. It differs from
318  * parse->targetList in that (for INSERT and UPDATE) it's been reordered
319  * to match the target table, and defaults have been filled in. Also,
320  * additional resjunk targets may be present. preprocess_targetlist()
321  * does most of this work, but note that more resjunk targets can get
322  * added during appendrel expansion. (Hence, upper_targets mustn't get
323  * set up till after that.)
324  */
326 
327  /* Fields filled during create_plan() for use in setrefs.c */
328  AttrNumber *grouping_map; /* for GroupingFunc fixup */
329  List *minmax_aggs; /* List of MinMaxAggInfos */
330 
331  MemoryContext planner_cxt; /* context holding PlannerInfo */
332 
333  double total_table_pages; /* # of pages in all non-dummy tables of
334  * query */
335 
336  double tuple_fraction; /* tuple_fraction passed to query_planner */
337  double limit_tuples; /* limit_tuples passed to query_planner */
338 
339  Index qual_security_level; /* minimum security_level for quals */
340  /* Note: qual_security_level is zero if there are no securityQuals */
341 
342  InheritanceKind inhTargetKind; /* indicates if the target relation is an
343  * inheritance child or partition or a
344  * partitioned table */
345  bool hasJoinRTEs; /* true if any RTEs are RTE_JOIN kind */
346  bool hasLateralRTEs; /* true if any RTEs are marked LATERAL */
347  bool hasHavingQual; /* true if havingQual was non-null */
348  bool hasPseudoConstantQuals; /* true if any RestrictInfo has
349  * pseudoconstant = true */
350  bool hasRecursion; /* true if planning a recursive WITH item */
351 
352  /* These fields are used only when hasRecursion is true: */
353  int wt_param_id; /* PARAM_EXEC ID for the work table */
354  struct Path *non_recursive_path; /* a path for non-recursive term */
355 
356  /* These fields are workspace for createplan.c */
357  Relids curOuterRels; /* outer rels above current node */
358  List *curOuterParams; /* not-yet-assigned NestLoopParams */
359 
360  /* optional private data for join_search_hook, e.g., GEQO */
362 
363  /* Does this query modify any partition key columns? */
365 };
366 
367 
368 /*
369  * In places where it's known that simple_rte_array[] must have been prepared
370  * already, we just index into it to fetch RTEs. In code that might be
371  * executed before or after entering query_planner(), use this macro.
372  */
373 #define planner_rt_fetch(rti, root) \
374  ((root)->simple_rte_array ? (root)->simple_rte_array[rti] : \
375  rt_fetch(rti, (root)->parse->rtable))
376 
377 /*
378  * If multiple relations are partitioned the same way, all such partitions
379  * will have a pointer to the same PartitionScheme. A list of PartitionScheme
380  * objects is attached to the PlannerInfo. By design, the partition scheme
381  * incorporates only the general properties of the partition method (LIST vs.
382  * RANGE, number of partitioning columns and the type information for each)
383  * and not the specific bounds.
384  *
385  * We store the opclass-declared input data types instead of the partition key
386  * datatypes since the former rather than the latter are used to compare
387  * partition bounds. Since partition key data types and the opclass declared
388  * input data types are expected to be binary compatible (per ResolveOpClass),
389  * both of those should have same byval and length properties.
390  */
391 typedef struct PartitionSchemeData
392 {
393  char strategy; /* partition strategy */
394  int16 partnatts; /* number of partition attributes */
395  Oid *partopfamily; /* OIDs of operator families */
396  Oid *partopcintype; /* OIDs of opclass declared input data types */
397  Oid *partcollation; /* OIDs of partitioning collations */
398 
399  /* Cached information about partition key data types. */
402 
403  /* Cached information about partition comparison functions. */
406 
408 
409 /*----------
410  * RelOptInfo
411  * Per-relation information for planning/optimization
412  *
413  * For planning purposes, a "base rel" is either a plain relation (a table)
414  * or the output of a sub-SELECT or function that appears in the range table.
415  * In either case it is uniquely identified by an RT index. A "joinrel"
416  * is the joining of two or more base rels. A joinrel is identified by
417  * the set of RT indexes for its component baserels. We create RelOptInfo
418  * nodes for each baserel and joinrel, and store them in the PlannerInfo's
419  * simple_rel_array and join_rel_list respectively.
420  *
421  * Note that there is only one joinrel for any given set of component
422  * baserels, no matter what order we assemble them in; so an unordered
423  * set is the right datatype to identify it with.
424  *
425  * We also have "other rels", which are like base rels in that they refer to
426  * single RT indexes; but they are not part of the join tree, and are given
427  * a different RelOptKind to identify them.
428  * Currently the only kind of otherrels are those made for member relations
429  * of an "append relation", that is an inheritance set or UNION ALL subquery.
430  * An append relation has a parent RTE that is a base rel, which represents
431  * the entire append relation. The member RTEs are otherrels. The parent
432  * is present in the query join tree but the members are not. The member
433  * RTEs and otherrels are used to plan the scans of the individual tables or
434  * subqueries of the append set; then the parent baserel is given Append
435  * and/or MergeAppend paths comprising the best paths for the individual
436  * member rels. (See comments for AppendRelInfo for more information.)
437  *
438  * At one time we also made otherrels to represent join RTEs, for use in
439  * handling join alias Vars. Currently this is not needed because all join
440  * alias Vars are expanded to non-aliased form during preprocess_expression.
441  *
442  * We also have relations representing joins between child relations of
443  * different partitioned tables. These relations are not added to
444  * join_rel_level lists as they are not joined directly by the dynamic
445  * programming algorithm.
446  *
447  * There is also a RelOptKind for "upper" relations, which are RelOptInfos
448  * that describe post-scan/join processing steps, such as aggregation.
449  * Many of the fields in these RelOptInfos are meaningless, but their Path
450  * fields always hold Paths showing ways to do that processing step.
451  *
452  * Lastly, there is a RelOptKind for "dead" relations, which are base rels
453  * that we have proven we don't need to join after all.
454  *
455  * Parts of this data structure are specific to various scan and join
456  * mechanisms. It didn't seem worth creating new node types for them.
457  *
458  * relids - Set of base-relation identifiers; it is a base relation
459  * if there is just one, a join relation if more than one
460  * rows - estimated number of tuples in the relation after restriction
461  * clauses have been applied (ie, output rows of a plan for it)
462  * consider_startup - true if there is any value in keeping plain paths for
463  * this rel on the basis of having cheap startup cost
464  * consider_param_startup - the same for parameterized paths
465  * reltarget - Default Path output tlist for this rel; normally contains
466  * Var and PlaceHolderVar nodes for the values we need to
467  * output from this relation.
468  * List is in no particular order, but all rels of an
469  * appendrel set must use corresponding orders.
470  * NOTE: in an appendrel child relation, may contain
471  * arbitrary expressions pulled up from a subquery!
472  * pathlist - List of Path nodes, one for each potentially useful
473  * method of generating the relation
474  * ppilist - ParamPathInfo nodes for parameterized Paths, if any
475  * cheapest_startup_path - the pathlist member with lowest startup cost
476  * (regardless of ordering) among the unparameterized paths;
477  * or NULL if there is no unparameterized path
478  * cheapest_total_path - the pathlist member with lowest total cost
479  * (regardless of ordering) among the unparameterized paths;
480  * or if there is no unparameterized path, the path with lowest
481  * total cost among the paths with minimum parameterization
482  * cheapest_unique_path - for caching cheapest path to produce unique
483  * (no duplicates) output from relation; NULL if not yet requested
484  * cheapest_parameterized_paths - best paths for their parameterizations;
485  * always includes cheapest_total_path, even if that's unparameterized
486  * direct_lateral_relids - rels this rel has direct LATERAL references to
487  * lateral_relids - required outer rels for LATERAL, as a Relids set
488  * (includes both direct and indirect lateral references)
489  *
490  * If the relation is a base relation it will have these fields set:
491  *
492  * relid - RTE index (this is redundant with the relids field, but
493  * is provided for convenience of access)
494  * rtekind - copy of RTE's rtekind field
495  * min_attr, max_attr - range of valid AttrNumbers for rel
496  * attr_needed - array of bitmapsets indicating the highest joinrel
497  * in which each attribute is needed; if bit 0 is set then
498  * the attribute is needed as part of final targetlist
499  * attr_widths - cache space for per-attribute width estimates;
500  * zero means not computed yet
501  * lateral_vars - lateral cross-references of rel, if any (list of
502  * Vars and PlaceHolderVars)
503  * lateral_referencers - relids of rels that reference this one laterally
504  * (includes both direct and indirect lateral references)
505  * indexlist - list of IndexOptInfo nodes for relation's indexes
506  * (always NIL if it's not a table)
507  * pages - number of disk pages in relation (zero if not a table)
508  * tuples - number of tuples in relation (not considering restrictions)
509  * allvisfrac - fraction of disk pages that are marked all-visible
510  * eclass_indexes - EquivalenceClasses that mention this rel (filled
511  * only after EC merging is complete)
512  * subroot - PlannerInfo for subquery (NULL if it's not a subquery)
513  * subplan_params - list of PlannerParamItems to be passed to subquery
514  *
515  * Note: for a subquery, tuples and subroot are not set immediately
516  * upon creation of the RelOptInfo object; they are filled in when
517  * set_subquery_pathlist processes the object.
518  *
519  * For otherrels that are appendrel members, these fields are filled
520  * in just as for a baserel, except we don't bother with lateral_vars.
521  *
522  * If the relation is either a foreign table or a join of foreign tables that
523  * all belong to the same foreign server and are assigned to the same user to
524  * check access permissions as (cf checkAsUser), these fields will be set:
525  *
526  * serverid - OID of foreign server, if foreign table (else InvalidOid)
527  * userid - OID of user to check access as (InvalidOid means current user)
528  * useridiscurrent - we've assumed that userid equals current user
529  * fdwroutine - function hooks for FDW, if foreign table (else NULL)
530  * fdw_private - private state for FDW, if foreign table (else NULL)
531  *
532  * Two fields are used to cache knowledge acquired during the join search
533  * about whether this rel is provably unique when being joined to given other
534  * relation(s), ie, it can have at most one row matching any given row from
535  * that join relation. Currently we only attempt such proofs, and thus only
536  * populate these fields, for base rels; but someday they might be used for
537  * join rels too:
538  *
539  * unique_for_rels - list of Relid sets, each one being a set of other
540  * rels for which this one has been proven unique
541  * non_unique_for_rels - list of Relid sets, each one being a set of
542  * other rels for which we have tried and failed to prove
543  * this one unique
544  *
545  * The presence of the following fields depends on the restrictions
546  * and joins that the relation participates in:
547  *
548  * baserestrictinfo - List of RestrictInfo nodes, containing info about
549  * each non-join qualification clause in which this relation
550  * participates (only used for base rels)
551  * baserestrictcost - Estimated cost of evaluating the baserestrictinfo
552  * clauses at a single tuple (only used for base rels)
553  * baserestrict_min_security - Smallest security_level found among
554  * clauses in baserestrictinfo
555  * joininfo - List of RestrictInfo nodes, containing info about each
556  * join clause in which this relation participates (but
557  * note this excludes clauses that might be derivable from
558  * EquivalenceClasses)
559  * has_eclass_joins - flag that EquivalenceClass joins are possible
560  *
561  * Note: Keeping a restrictinfo list in the RelOptInfo is useful only for
562  * base rels, because for a join rel the set of clauses that are treated as
563  * restrict clauses varies depending on which sub-relations we choose to join.
564  * (For example, in a 3-base-rel join, a clause relating rels 1 and 2 must be
565  * treated as a restrictclause if we join {1} and {2 3} to make {1 2 3}; but
566  * if we join {1 2} and {3} then that clause will be a restrictclause in {1 2}
567  * and should not be processed again at the level of {1 2 3}.) Therefore,
568  * the restrictinfo list in the join case appears in individual JoinPaths
569  * (field joinrestrictinfo), not in the parent relation. But it's OK for
570  * the RelOptInfo to store the joininfo list, because that is the same
571  * for a given rel no matter how we form it.
572  *
573  * We store baserestrictcost in the RelOptInfo (for base relations) because
574  * we know we will need it at least once (to price the sequential scan)
575  * and may need it multiple times to price index scans.
576  *
577  * If the relation is partitioned, these fields will be set:
578  *
579  * part_scheme - Partitioning scheme of the relation
580  * nparts - Number of partitions
581  * boundinfo - Partition bounds
582  * partition_qual - Partition constraint if not the root
583  * part_rels - RelOptInfos for each partition
584  * partexprs, nullable_partexprs - Partition key expressions
585  * partitioned_child_rels - RT indexes of unpruned partitions of
586  * this relation that are partitioned tables
587  * themselves, in hierarchical order
588  *
589  * Note: A base relation always has only one set of partition keys, but a join
590  * relation may have as many sets of partition keys as the number of relations
591  * being joined. partexprs and nullable_partexprs are arrays containing
592  * part_scheme->partnatts elements each. Each of these elements is a list of
593  * partition key expressions. For a base relation each list in partexprs
594  * contains only one expression and nullable_partexprs is not populated. For a
595  * join relation, partexprs and nullable_partexprs contain partition key
596  * expressions from non-nullable and nullable relations resp. Lists at any
597  * given position in those arrays together contain as many elements as the
598  * number of joining relations.
599  *----------
600  */
601 typedef enum RelOptKind
602 {
610 } RelOptKind;
611 
612 /*
613  * Is the given relation a simple relation i.e a base or "other" member
614  * relation?
615  */
616 #define IS_SIMPLE_REL(rel) \
617  ((rel)->reloptkind == RELOPT_BASEREL || \
618  (rel)->reloptkind == RELOPT_OTHER_MEMBER_REL)
619 
620 /* Is the given relation a join relation? */
621 #define IS_JOIN_REL(rel) \
622  ((rel)->reloptkind == RELOPT_JOINREL || \
623  (rel)->reloptkind == RELOPT_OTHER_JOINREL)
624 
625 /* Is the given relation an upper relation? */
626 #define IS_UPPER_REL(rel) \
627  ((rel)->reloptkind == RELOPT_UPPER_REL || \
628  (rel)->reloptkind == RELOPT_OTHER_UPPER_REL)
629 
630 /* Is the given relation an "other" relation? */
631 #define IS_OTHER_REL(rel) \
632  ((rel)->reloptkind == RELOPT_OTHER_MEMBER_REL || \
633  (rel)->reloptkind == RELOPT_OTHER_JOINREL || \
634  (rel)->reloptkind == RELOPT_OTHER_UPPER_REL)
635 
636 typedef struct RelOptInfo
637 {
639 
641 
642  /* all relations included in this RelOptInfo */
643  Relids relids; /* set of base relids (rangetable indexes) */
644 
645  /* size estimates generated by planner */
646  double rows; /* estimated number of result tuples */
647 
648  /* per-relation planner control flags */
649  bool consider_startup; /* keep cheap-startup-cost paths? */
650  bool consider_param_startup; /* ditto, for parameterized paths? */
651  bool consider_parallel; /* consider parallel paths? */
652 
653  /* default result targetlist for Paths scanning this relation */
654  struct PathTarget *reltarget; /* list of Vars/Exprs, cost, width */
655 
656  /* materialization information */
657  List *pathlist; /* Path structures */
658  List *ppilist; /* ParamPathInfos used in pathlist */
659  List *partial_pathlist; /* partial Paths */
664 
665  /* parameterization information needed for both base rels and join rels */
666  /* (see also lateral_vars and lateral_referencers) */
667  Relids direct_lateral_relids; /* rels directly laterally referenced */
668  Relids lateral_relids; /* minimum parameterization of rel */
669 
670  /* information about a base rel (not set for join rels!) */
672  Oid reltablespace; /* containing tablespace */
673  RTEKind rtekind; /* RELATION, SUBQUERY, FUNCTION, etc */
674  AttrNumber min_attr; /* smallest attrno of rel (often <0) */
675  AttrNumber max_attr; /* largest attrno of rel */
676  Relids *attr_needed; /* array indexed [min_attr .. max_attr] */
677  int32 *attr_widths; /* array indexed [min_attr .. max_attr] */
678  List *lateral_vars; /* LATERAL Vars and PHVs referenced by rel */
679  Relids lateral_referencers; /* rels that reference me laterally */
680  List *indexlist; /* list of IndexOptInfo */
681  List *statlist; /* list of StatisticExtInfo */
682  BlockNumber pages; /* size estimates derived from pg_class */
683  double tuples;
684  double allvisfrac;
685  Bitmapset *eclass_indexes; /* Indexes in PlannerInfo's eq_classes list of
686  * ECs that mention this rel */
687  PlannerInfo *subroot; /* if subquery */
688  List *subplan_params; /* if subquery */
689  int rel_parallel_workers; /* wanted number of parallel workers */
690 
691  /* Information about foreign tables and foreign joins */
692  Oid serverid; /* identifies server for the table or join */
693  Oid userid; /* identifies user to check access as */
694  bool useridiscurrent; /* join is only valid for current user */
695  /* use "struct FdwRoutine" to avoid including fdwapi.h here */
697  void *fdw_private;
698 
699  /* cache space for remembering if we have proven this relation unique */
700  List *unique_for_rels; /* known unique for these other relid
701  * set(s) */
702  List *non_unique_for_rels; /* known not unique for these set(s) */
703 
704  /* used by various scans and joins: */
705  List *baserestrictinfo; /* RestrictInfo structures (if base rel) */
706  QualCost baserestrictcost; /* cost of evaluating the above */
707  Index baserestrict_min_security; /* min security_level found in
708  * baserestrictinfo */
709  List *joininfo; /* RestrictInfo structures for join clauses
710  * involving this rel */
711  bool has_eclass_joins; /* T means joininfo is incomplete */
712 
713  /* used by partitionwise joins: */
714  bool consider_partitionwise_join; /* consider partitionwise join
715  * paths? (if partitioned rel) */
716  Relids top_parent_relids; /* Relids of topmost parents (if "other"
717  * rel) */
718 
719  /* used for partitioned relations */
720  PartitionScheme part_scheme; /* Partitioning scheme. */
721  int nparts; /* number of partitions */
722  struct PartitionBoundInfoData *boundinfo; /* Partition bounds */
723  List *partition_qual; /* partition constraint */
724  struct RelOptInfo **part_rels; /* Array of RelOptInfos of partitions,
725  * stored in the same order of bounds */
726  List **partexprs; /* Non-nullable partition key expressions. */
727  List **nullable_partexprs; /* Nullable partition key expressions. */
728  List *partitioned_child_rels; /* List of RT indexes. */
729 } RelOptInfo;
730 
731 /*
732  * Is given relation partitioned?
733  *
734  * It's not enough to test whether rel->part_scheme is set, because it might
735  * be that the basic partitioning properties of the input relations matched
736  * but the partition bounds did not. Also, if we are able to prove a rel
737  * dummy (empty), we should henceforth treat it as unpartitioned.
738  */
739 #define IS_PARTITIONED_REL(rel) \
740  ((rel)->part_scheme && (rel)->boundinfo && (rel)->nparts > 0 && \
741  (rel)->part_rels && !IS_DUMMY_REL(rel))
742 
743 /*
744  * Convenience macro to make sure that a partitioned relation has all the
745  * required members set.
746  */
747 #define REL_HAS_ALL_PART_PROPS(rel) \
748  ((rel)->part_scheme && (rel)->boundinfo && (rel)->nparts > 0 && \
749  (rel)->part_rels && (rel)->partexprs && (rel)->nullable_partexprs)
750 
751 /*
752  * IndexOptInfo
753  * Per-index information for planning/optimization
754  *
755  * indexkeys[], indexcollations[] each have ncolumns entries.
756  * opfamily[], and opcintype[] each have nkeycolumns entries. They do
757  * not contain any information about included attributes.
758  *
759  * sortopfamily[], reverse_sort[], and nulls_first[] have
760  * nkeycolumns entries, if the index is ordered; but if it is unordered,
761  * those pointers are NULL.
762  *
763  * Zeroes in the indexkeys[] array indicate index columns that are
764  * expressions; there is one element in indexprs for each such column.
765  *
766  * For an ordered index, reverse_sort[] and nulls_first[] describe the
767  * sort ordering of a forward indexscan; we can also consider a backward
768  * indexscan, which will generate the reverse ordering.
769  *
770  * The indexprs and indpred expressions have been run through
771  * prepqual.c and eval_const_expressions() for ease of matching to
772  * WHERE clauses. indpred is in implicit-AND form.
773  *
774  * indextlist is a TargetEntry list representing the index columns.
775  * It provides an equivalent base-relation Var for each simple column,
776  * and links to the matching indexprs element for each expression column.
777  *
778  * While most of these fields are filled when the IndexOptInfo is created
779  * (by plancat.c), indrestrictinfo and predOK are set later, in
780  * check_index_predicates().
781  */
782 #ifndef HAVE_INDEXOPTINFO_TYPEDEF
783 typedef struct IndexOptInfo IndexOptInfo;
784 #define HAVE_INDEXOPTINFO_TYPEDEF 1
785 #endif
786 
788 {
790 
791  Oid indexoid; /* OID of the index relation */
792  Oid reltablespace; /* tablespace of index (not table) */
793  RelOptInfo *rel; /* back-link to index's table */
794 
795  /* index-size statistics (from pg_class and elsewhere) */
796  BlockNumber pages; /* number of disk pages in index */
797  double tuples; /* number of index tuples in index */
798  int tree_height; /* index tree height, or -1 if unknown */
799 
800  /* index descriptor information */
801  int ncolumns; /* number of columns in index */
802  int nkeycolumns; /* number of key columns in index */
803  int *indexkeys; /* column numbers of index's attributes both
804  * key and included columns, or 0 */
805  Oid *indexcollations; /* OIDs of collations of index columns */
806  Oid *opfamily; /* OIDs of operator families for columns */
807  Oid *opcintype; /* OIDs of opclass declared input data types */
808  Oid *sortopfamily; /* OIDs of btree opfamilies, if orderable */
809  bool *reverse_sort; /* is sort order descending? */
810  bool *nulls_first; /* do NULLs come first in the sort order? */
811  bool *canreturn; /* which index cols can be returned in an
812  * index-only scan? */
813  Oid relam; /* OID of the access method (in pg_am) */
814 
815  List *indexprs; /* expressions for non-simple index columns */
816  List *indpred; /* predicate if a partial index, else NIL */
817 
818  List *indextlist; /* targetlist representing index columns */
819 
820  List *indrestrictinfo; /* parent relation's baserestrictinfo
821  * list, less any conditions implied by
822  * the index's predicate (unless it's a
823  * target rel, see comments in
824  * check_index_predicates()) */
825 
826  bool predOK; /* true if index predicate matches query */
827  bool unique; /* true if a unique index */
828  bool immediate; /* is uniqueness enforced immediately? */
829  bool hypothetical; /* true if index doesn't really exist */
830 
831  /* Remaining fields are copied from the index AM's API struct: */
832  bool amcanorderbyop; /* does AM support order by operator result? */
833  bool amoptionalkey; /* can query omit key for the first column? */
834  bool amsearcharray; /* can AM handle ScalarArrayOpExpr quals? */
835  bool amsearchnulls; /* can AM search for NULL/NOT NULL entries? */
836  bool amhasgettuple; /* does AM have amgettuple interface? */
837  bool amhasgetbitmap; /* does AM have amgetbitmap interface? */
838  bool amcanparallel; /* does AM support parallel scan? */
839  /* Rather than include amapi.h here, we declare amcostestimate like this */
840  void (*amcostestimate) (); /* AM's cost estimator */
841 };
842 
843 /*
844  * ForeignKeyOptInfo
845  * Per-foreign-key information for planning/optimization
846  *
847  * The per-FK-column arrays can be fixed-size because we allow at most
848  * INDEX_MAX_KEYS columns in a foreign key constraint. Each array has
849  * nkeys valid entries.
850  */
851 typedef struct ForeignKeyOptInfo
852 {
854 
855  /* Basic data about the foreign key (fetched from catalogs): */
856  Index con_relid; /* RT index of the referencing table */
857  Index ref_relid; /* RT index of the referenced table */
858  int nkeys; /* number of columns in the foreign key */
859  AttrNumber conkey[INDEX_MAX_KEYS]; /* cols in referencing table */
860  AttrNumber confkey[INDEX_MAX_KEYS]; /* cols in referenced table */
861  Oid conpfeqop[INDEX_MAX_KEYS]; /* PK = FK operator OIDs */
862 
863  /* Derived info about whether FK's equality conditions match the query: */
864  int nmatched_ec; /* # of FK cols matched by ECs */
865  int nmatched_rcols; /* # of FK cols matched by non-EC rinfos */
866  int nmatched_ri; /* total # of non-EC rinfos matched to FK */
867  /* Pointer to eclass matching each column's condition, if there is one */
869  /* List of non-EC RestrictInfos matching each column's condition */
872 
873 /*
874  * StatisticExtInfo
875  * Information about extended statistics for planning/optimization
876  *
877  * Each pg_statistic_ext row is represented by one or more nodes of this
878  * type, or even zero if ANALYZE has not computed them.
879  */
880 typedef struct StatisticExtInfo
881 {
883 
884  Oid statOid; /* OID of the statistics row */
885  RelOptInfo *rel; /* back-link to statistic's table */
886  char kind; /* statistic kind of this entry */
887  Bitmapset *keys; /* attnums of the columns covered */
889 
890 /*
891  * EquivalenceClasses
892  *
893  * Whenever we can determine that a mergejoinable equality clause A = B is
894  * not delayed by any outer join, we create an EquivalenceClass containing
895  * the expressions A and B to record this knowledge. If we later find another
896  * equivalence B = C, we add C to the existing EquivalenceClass; this may
897  * require merging two existing EquivalenceClasses. At the end of the qual
898  * distribution process, we have sets of values that are known all transitively
899  * equal to each other, where "equal" is according to the rules of the btree
900  * operator family(s) shown in ec_opfamilies, as well as the collation shown
901  * by ec_collation. (We restrict an EC to contain only equalities whose
902  * operators belong to the same set of opfamilies. This could probably be
903  * relaxed, but for now it's not worth the trouble, since nearly all equality
904  * operators belong to only one btree opclass anyway. Similarly, we suppose
905  * that all or none of the input datatypes are collatable, so that a single
906  * collation value is sufficient.)
907  *
908  * We also use EquivalenceClasses as the base structure for PathKeys, letting
909  * us represent knowledge about different sort orderings being equivalent.
910  * Since every PathKey must reference an EquivalenceClass, we will end up
911  * with single-member EquivalenceClasses whenever a sort key expression has
912  * not been equivalenced to anything else. It is also possible that such an
913  * EquivalenceClass will contain a volatile expression ("ORDER BY random()"),
914  * which is a case that can't arise otherwise since clauses containing
915  * volatile functions are never considered mergejoinable. We mark such
916  * EquivalenceClasses specially to prevent them from being merged with
917  * ordinary EquivalenceClasses. Also, for volatile expressions we have
918  * to be careful to match the EquivalenceClass to the correct targetlist
919  * entry: consider SELECT random() AS a, random() AS b ... ORDER BY b,a.
920  * So we record the SortGroupRef of the originating sort clause.
921  *
922  * We allow equality clauses appearing below the nullable side of an outer join
923  * to form EquivalenceClasses, but these have a slightly different meaning:
924  * the included values might be all NULL rather than all the same non-null
925  * values. See src/backend/optimizer/README for more on that point.
926  *
927  * NB: if ec_merged isn't NULL, this class has been merged into another, and
928  * should be ignored in favor of using the pointed-to class.
929  */
930 typedef struct EquivalenceClass
931 {
933 
934  List *ec_opfamilies; /* btree operator family OIDs */
935  Oid ec_collation; /* collation, if datatypes are collatable */
936  List *ec_members; /* list of EquivalenceMembers */
937  List *ec_sources; /* list of generating RestrictInfos */
938  List *ec_derives; /* list of derived RestrictInfos */
939  Relids ec_relids; /* all relids appearing in ec_members, except
940  * for child members (see below) */
941  bool ec_has_const; /* any pseudoconstants in ec_members? */
942  bool ec_has_volatile; /* the (sole) member is a volatile expr */
943  bool ec_below_outer_join; /* equivalence applies below an OJ */
944  bool ec_broken; /* failed to generate needed clauses? */
945  Index ec_sortref; /* originating sortclause label, or 0 */
946  Index ec_min_security; /* minimum security_level in ec_sources */
947  Index ec_max_security; /* maximum security_level in ec_sources */
948  struct EquivalenceClass *ec_merged; /* set if merged into another EC */
950 
951 /*
952  * If an EC contains a const and isn't below-outer-join, any PathKey depending
953  * on it must be redundant, since there's only one possible value of the key.
954  */
955 #define EC_MUST_BE_REDUNDANT(eclass) \
956  ((eclass)->ec_has_const && !(eclass)->ec_below_outer_join)
957 
958 /*
959  * EquivalenceMember - one member expression of an EquivalenceClass
960  *
961  * em_is_child signifies that this element was built by transposing a member
962  * for an appendrel parent relation to represent the corresponding expression
963  * for an appendrel child. These members are used for determining the
964  * pathkeys of scans on the child relation and for explicitly sorting the
965  * child when necessary to build a MergeAppend path for the whole appendrel
966  * tree. An em_is_child member has no impact on the properties of the EC as a
967  * whole; in particular the EC's ec_relids field does NOT include the child
968  * relation. An em_is_child member should never be marked em_is_const nor
969  * cause ec_has_const or ec_has_volatile to be set, either. Thus, em_is_child
970  * members are not really full-fledged members of the EC, but just reflections
971  * or doppelgangers of real members. Most operations on EquivalenceClasses
972  * should ignore em_is_child members, and those that don't should test
973  * em_relids to make sure they only consider relevant members.
974  *
975  * em_datatype is usually the same as exprType(em_expr), but can be
976  * different when dealing with a binary-compatible opfamily; in particular
977  * anyarray_ops would never work without this. Use em_datatype when
978  * looking up a specific btree operator to work with this expression.
979  */
980 typedef struct EquivalenceMember
981 {
983 
984  Expr *em_expr; /* the expression represented */
985  Relids em_relids; /* all relids appearing in em_expr */
986  Relids em_nullable_relids; /* nullable by lower outer joins */
987  bool em_is_const; /* expression is pseudoconstant? */
988  bool em_is_child; /* derived version for a child relation? */
989  Oid em_datatype; /* the "nominal type" used by the opfamily */
991 
992 /*
993  * PathKeys
994  *
995  * The sort ordering of a path is represented by a list of PathKey nodes.
996  * An empty list implies no known ordering. Otherwise the first item
997  * represents the primary sort key, the second the first secondary sort key,
998  * etc. The value being sorted is represented by linking to an
999  * EquivalenceClass containing that value and including pk_opfamily among its
1000  * ec_opfamilies. The EquivalenceClass tells which collation to use, too.
1001  * This is a convenient method because it makes it trivial to detect
1002  * equivalent and closely-related orderings. (See optimizer/README for more
1003  * information.)
1004  *
1005  * Note: pk_strategy is either BTLessStrategyNumber (for ASC) or
1006  * BTGreaterStrategyNumber (for DESC). We assume that all ordering-capable
1007  * index types will use btree-compatible strategy numbers.
1008  */
1009 typedef struct PathKey
1010 {
1012 
1013  EquivalenceClass *pk_eclass; /* the value that is ordered */
1014  Oid pk_opfamily; /* btree opfamily defining the ordering */
1015  int pk_strategy; /* sort direction (ASC or DESC) */
1016  bool pk_nulls_first; /* do NULLs come before normal values? */
1017 } PathKey;
1018 
1019 
1020 /*
1021  * PathTarget
1022  *
1023  * This struct contains what we need to know during planning about the
1024  * targetlist (output columns) that a Path will compute. Each RelOptInfo
1025  * includes a default PathTarget, which its individual Paths may simply
1026  * reference. However, in some cases a Path may compute outputs different
1027  * from other Paths, and in that case we make a custom PathTarget for it.
1028  * For example, an indexscan might return index expressions that would
1029  * otherwise need to be explicitly calculated. (Note also that "upper"
1030  * relations generally don't have useful default PathTargets.)
1031  *
1032  * exprs contains bare expressions; they do not have TargetEntry nodes on top,
1033  * though those will appear in finished Plans.
1034  *
1035  * sortgrouprefs[] is an array of the same length as exprs, containing the
1036  * corresponding sort/group refnos, or zeroes for expressions not referenced
1037  * by sort/group clauses. If sortgrouprefs is NULL (which it generally is in
1038  * RelOptInfo.reltarget targets; only upper-level Paths contain this info),
1039  * we have not identified sort/group columns in this tlist. This allows us to
1040  * deal with sort/group refnos when needed with less expense than including
1041  * TargetEntry nodes in the exprs list.
1042  */
1043 typedef struct PathTarget
1044 {
1046  List *exprs; /* list of expressions to be computed */
1047  Index *sortgrouprefs; /* corresponding sort/group refnos, or 0 */
1048  QualCost cost; /* cost of evaluating the expressions */
1049  int width; /* estimated avg width of result tuples */
1050 } PathTarget;
1051 
1052 /* Convenience macro to get a sort/group refno from a PathTarget */
1053 #define get_pathtarget_sortgroupref(target, colno) \
1054  ((target)->sortgrouprefs ? (target)->sortgrouprefs[colno] : (Index) 0)
1055 
1056 
1057 /*
1058  * ParamPathInfo
1059  *
1060  * All parameterized paths for a given relation with given required outer rels
1061  * link to a single ParamPathInfo, which stores common information such as
1062  * the estimated rowcount for this parameterization. We do this partly to
1063  * avoid recalculations, but mostly to ensure that the estimated rowcount
1064  * is in fact the same for every such path.
1065  *
1066  * Note: ppi_clauses is only used in ParamPathInfos for base relation paths;
1067  * in join cases it's NIL because the set of relevant clauses varies depending
1068  * on how the join is formed. The relevant clauses will appear in each
1069  * parameterized join path's joinrestrictinfo list, instead.
1070  */
1071 typedef struct ParamPathInfo
1072 {
1074 
1075  Relids ppi_req_outer; /* rels supplying parameters used by path */
1076  double ppi_rows; /* estimated number of result tuples */
1077  List *ppi_clauses; /* join clauses available from outer rels */
1078 } ParamPathInfo;
1079 
1080 
1081 /*
1082  * Type "Path" is used as-is for sequential-scan paths, as well as some other
1083  * simple plan types that we don't need any extra information in the path for.
1084  * For other path types it is the first component of a larger struct.
1085  *
1086  * "pathtype" is the NodeTag of the Plan node we could build from this Path.
1087  * It is partially redundant with the Path's NodeTag, but allows us to use
1088  * the same Path type for multiple Plan types when there is no need to
1089  * distinguish the Plan type during path processing.
1090  *
1091  * "parent" identifies the relation this Path scans, and "pathtarget"
1092  * describes the precise set of output columns the Path would compute.
1093  * In simple cases all Paths for a given rel share the same targetlist,
1094  * which we represent by having path->pathtarget equal to parent->reltarget.
1095  *
1096  * "param_info", if not NULL, links to a ParamPathInfo that identifies outer
1097  * relation(s) that provide parameter values to each scan of this path.
1098  * That means this path can only be joined to those rels by means of nestloop
1099  * joins with this path on the inside. Also note that a parameterized path
1100  * is responsible for testing all "movable" joinclauses involving this rel
1101  * and the specified outer rel(s).
1102  *
1103  * "rows" is the same as parent->rows in simple paths, but in parameterized
1104  * paths and UniquePaths it can be less than parent->rows, reflecting the
1105  * fact that we've filtered by extra join conditions or removed duplicates.
1106  *
1107  * "pathkeys" is a List of PathKey nodes (see above), describing the sort
1108  * ordering of the path's output rows.
1109  */
1110 typedef struct Path
1111 {
1113 
1114  NodeTag pathtype; /* tag identifying scan/join method */
1115 
1116  RelOptInfo *parent; /* the relation this path can build */
1117  PathTarget *pathtarget; /* list of Vars/Exprs, cost, width */
1118 
1119  ParamPathInfo *param_info; /* parameterization info, or NULL if none */
1120 
1121  bool parallel_aware; /* engage parallel-aware logic? */
1122  bool parallel_safe; /* OK to use as part of parallel plan? */
1123  int parallel_workers; /* desired # of workers; 0 = not parallel */
1124 
1125  /* estimated size/costs for path (see costsize.c for more info) */
1126  double rows; /* estimated number of result tuples */
1127  Cost startup_cost; /* cost expended before fetching any tuples */
1128  Cost total_cost; /* total cost (assuming all tuples fetched) */
1129 
1130  List *pathkeys; /* sort ordering of path's output */
1131  /* pathkeys is a List of PathKey nodes; see above */
1132 } Path;
1133 
1134 /* Macro for extracting a path's parameterization relids; beware double eval */
1135 #define PATH_REQ_OUTER(path) \
1136  ((path)->param_info ? (path)->param_info->ppi_req_outer : (Relids) NULL)
1137 
1138 /*----------
1139  * IndexPath represents an index scan over a single index.
1140  *
1141  * This struct is used for both regular indexscans and index-only scans;
1142  * path.pathtype is T_IndexScan or T_IndexOnlyScan to show which is meant.
1143  *
1144  * 'indexinfo' is the index to be scanned.
1145  *
1146  * 'indexclauses' is a list of IndexClause nodes, each representing one
1147  * index-checkable restriction, with implicit AND semantics across the list.
1148  * An empty list implies a full index scan.
1149  *
1150  * 'indexorderbys', if not NIL, is a list of ORDER BY expressions that have
1151  * been found to be usable as ordering operators for an amcanorderbyop index.
1152  * The list must match the path's pathkeys, ie, one expression per pathkey
1153  * in the same order. These are not RestrictInfos, just bare expressions,
1154  * since they generally won't yield booleans. It's guaranteed that each
1155  * expression has the index key on the left side of the operator.
1156  *
1157  * 'indexorderbycols' is an integer list of index column numbers (zero-based)
1158  * of the same length as 'indexorderbys', showing which index column each
1159  * ORDER BY expression is meant to be used with. (There is no restriction
1160  * on which index column each ORDER BY can be used with.)
1161  *
1162  * 'indexscandir' is one of:
1163  * ForwardScanDirection: forward scan of an ordered index
1164  * BackwardScanDirection: backward scan of an ordered index
1165  * NoMovementScanDirection: scan of an unordered index, or don't care
1166  * (The executor doesn't care whether it gets ForwardScanDirection or
1167  * NoMovementScanDirection for an indexscan, but the planner wants to
1168  * distinguish ordered from unordered indexes for building pathkeys.)
1169  *
1170  * 'indextotalcost' and 'indexselectivity' are saved in the IndexPath so that
1171  * we need not recompute them when considering using the same index in a
1172  * bitmap index/heap scan (see BitmapHeapPath). The costs of the IndexPath
1173  * itself represent the costs of an IndexScan or IndexOnlyScan plan type.
1174  *----------
1175  */
1176 typedef struct IndexPath
1177 {
1186 } IndexPath;
1187 
1188 /*
1189  * Each IndexClause references a RestrictInfo node from the query's WHERE
1190  * or JOIN conditions, and shows how that restriction can be applied to
1191  * the particular index. We support both indexclauses that are directly
1192  * usable by the index machinery, which are typically of the form
1193  * "indexcol OP pseudoconstant", and those from which an indexable qual
1194  * can be derived. The simplest such transformation is that a clause
1195  * of the form "pseudoconstant OP indexcol" can be commuted to produce an
1196  * indexable qual (the index machinery expects the indexcol to be on the
1197  * left always). Another example is that we might be able to extract an
1198  * indexable range condition from a LIKE condition, as in "x LIKE 'foo%bar'"
1199  * giving rise to "x >= 'foo' AND x < 'fop'". Derivation of such lossy
1200  * conditions is done by a planner support function attached to the
1201  * indexclause's top-level function or operator.
1202  *
1203  * indexquals is a list of RestrictInfos for the directly-usable index
1204  * conditions associated with this IndexClause. In the simplest case
1205  * it's a one-element list whose member is iclause->rinfo. Otherwise,
1206  * it contains one or more directly-usable indexqual conditions extracted
1207  * from the given clause. The 'lossy' flag indicates whether the
1208  * indexquals are semantically equivalent to the original clause, or
1209  * represent a weaker condition.
1210  *
1211  * Normally, indexcol is the index of the single index column the clause
1212  * works on, and indexcols is NIL. But if the clause is a RowCompareExpr,
1213  * indexcol is the index of the leading column, and indexcols is a list of
1214  * all the affected columns. (Note that indexcols matches up with the
1215  * columns of the actual indexable RowCompareExpr in indexquals, which
1216  * might be different from the original in rinfo.)
1217  *
1218  * An IndexPath's IndexClause list is required to be ordered by index
1219  * column, i.e. the indexcol values must form a nondecreasing sequence.
1220  * (The order of multiple clauses for the same index column is unspecified.)
1221  */
1222 typedef struct IndexClause
1223 {
1225  struct RestrictInfo *rinfo; /* original restriction or join clause */
1226  List *indexquals; /* indexqual(s) derived from it */
1227  bool lossy; /* are indexquals a lossy version of clause? */
1228  AttrNumber indexcol; /* index column the clause uses (zero-based) */
1229  List *indexcols; /* multiple index columns, if RowCompare */
1230 } IndexClause;
1231 
1232 /*
1233  * BitmapHeapPath represents one or more indexscans that generate TID bitmaps
1234  * instead of directly accessing the heap, followed by AND/OR combinations
1235  * to produce a single bitmap, followed by a heap scan that uses the bitmap.
1236  * Note that the output is always considered unordered, since it will come
1237  * out in physical heap order no matter what the underlying indexes did.
1238  *
1239  * The individual indexscans are represented by IndexPath nodes, and any
1240  * logic on top of them is represented by a tree of BitmapAndPath and
1241  * BitmapOrPath nodes. Notice that we can use the same IndexPath node both
1242  * to represent a regular (or index-only) index scan plan, and as the child
1243  * of a BitmapHeapPath that represents scanning the same index using a
1244  * BitmapIndexScan. The startup_cost and total_cost figures of an IndexPath
1245  * always represent the costs to use it as a regular (or index-only)
1246  * IndexScan. The costs of a BitmapIndexScan can be computed using the
1247  * IndexPath's indextotalcost and indexselectivity.
1248  */
1249 typedef struct BitmapHeapPath
1250 {
1252  Path *bitmapqual; /* IndexPath, BitmapAndPath, BitmapOrPath */
1253 } BitmapHeapPath;
1254 
1255 /*
1256  * BitmapAndPath represents a BitmapAnd plan node; it can only appear as
1257  * part of the substructure of a BitmapHeapPath. The Path structure is
1258  * a bit more heavyweight than we really need for this, but for simplicity
1259  * we make it a derivative of Path anyway.
1260  */
1261 typedef struct BitmapAndPath
1262 {
1264  List *bitmapquals; /* IndexPaths and BitmapOrPaths */
1266 } BitmapAndPath;
1267 
1268 /*
1269  * BitmapOrPath represents a BitmapOr plan node; it can only appear as
1270  * part of the substructure of a BitmapHeapPath. The Path structure is
1271  * a bit more heavyweight than we really need for this, but for simplicity
1272  * we make it a derivative of Path anyway.
1273  */
1274 typedef struct BitmapOrPath
1275 {
1277  List *bitmapquals; /* IndexPaths and BitmapAndPaths */
1279 } BitmapOrPath;
1280 
1281 /*
1282  * TidPath represents a scan by TID
1283  *
1284  * tidquals is an implicitly OR'ed list of qual expressions of the form
1285  * "CTID = pseudoconstant", or "CTID = ANY(pseudoconstant_array)",
1286  * or a CurrentOfExpr for the relation.
1287  */
1288 typedef struct TidPath
1289 {
1291  List *tidquals; /* qual(s) involving CTID = something */
1292 } TidPath;
1293 
1294 /*
1295  * SubqueryScanPath represents a scan of an unflattened subquery-in-FROM
1296  *
1297  * Note that the subpath comes from a different planning domain; for example
1298  * RTE indexes within it mean something different from those known to the
1299  * SubqueryScanPath. path.parent->subroot is the planning context needed to
1300  * interpret the subpath.
1301  */
1302 typedef struct SubqueryScanPath
1303 {
1305  Path *subpath; /* path representing subquery execution */
1307 
1308 /*
1309  * ForeignPath represents a potential scan of a foreign table, foreign join
1310  * or foreign upper-relation.
1311  *
1312  * fdw_private stores FDW private data about the scan. While fdw_private is
1313  * not actually touched by the core code during normal operations, it's
1314  * generally a good idea to use a representation that can be dumped by
1315  * nodeToString(), so that you can examine the structure during debugging
1316  * with tools like pprint().
1317  */
1318 typedef struct ForeignPath
1319 {
1323 } ForeignPath;
1324 
1325 /*
1326  * CustomPath represents a table scan done by some out-of-core extension.
1327  *
1328  * We provide a set of hooks here - which the provider must take care to set
1329  * up correctly - to allow extensions to supply their own methods of scanning
1330  * a relation. For example, a provider might provide GPU acceleration, a
1331  * cache-based scan, or some other kind of logic we haven't dreamed up yet.
1332  *
1333  * CustomPaths can be injected into the planning process for a relation by
1334  * set_rel_pathlist_hook functions.
1335  *
1336  * Core code must avoid assuming that the CustomPath is only as large as
1337  * the structure declared here; providers are allowed to make it the first
1338  * element in a larger structure. (Since the planner never copies Paths,
1339  * this doesn't add any complication.) However, for consistency with the
1340  * FDW case, we provide a "custom_private" field in CustomPath; providers
1341  * may prefer to use that rather than define another struct type.
1342  */
1343 
1344 struct CustomPathMethods;
1345 
1346 typedef struct CustomPath
1347 {
1349  uint32 flags; /* mask of CUSTOMPATH_* flags, see
1350  * nodes/extensible.h */
1351  List *custom_paths; /* list of child Path nodes, if any */
1354 } CustomPath;
1355 
1356 /*
1357  * AppendPath represents an Append plan, ie, successive execution of
1358  * several member plans.
1359  *
1360  * For partial Append, 'subpaths' contains non-partial subpaths followed by
1361  * partial subpaths.
1362  *
1363  * Note: it is possible for "subpaths" to contain only one, or even no,
1364  * elements. These cases are optimized during create_append_plan.
1365  * In particular, an AppendPath with no subpaths is a "dummy" path that
1366  * is created to represent the case that a relation is provably empty.
1367  * (This is a convenient representation because it means that when we build
1368  * an appendrel and find that all its children have been excluded, no extra
1369  * action is needed to recognize the relation as dummy.)
1370  */
1371 typedef struct AppendPath
1372 {
1374  /* RT indexes of non-leaf tables in a partition tree */
1376  List *subpaths; /* list of component Paths */
1377  /* Index of first partial path in subpaths; list_length(subpaths) if none */
1379  double limit_tuples; /* hard limit on output tuples, or -1 */
1380 } AppendPath;
1381 
1382 #define IS_DUMMY_APPEND(p) \
1383  (IsA((p), AppendPath) && ((AppendPath *) (p))->subpaths == NIL)
1384 
1385 /*
1386  * A relation that's been proven empty will have one path that is dummy
1387  * (but might have projection paths on top). For historical reasons,
1388  * this is provided as a macro that wraps is_dummy_rel().
1389  */
1390 #define IS_DUMMY_REL(r) is_dummy_rel(r)
1391 extern bool is_dummy_rel(RelOptInfo *rel);
1392 
1393 /*
1394  * MergeAppendPath represents a MergeAppend plan, ie, the merging of sorted
1395  * results from several member plans to produce similarly-sorted output.
1396  */
1397 typedef struct MergeAppendPath
1398 {
1400  /* RT indexes of non-leaf tables in a partition tree */
1402  List *subpaths; /* list of component Paths */
1403  double limit_tuples; /* hard limit on output tuples, or -1 */
1404 } MergeAppendPath;
1405 
1406 /*
1407  * GroupResultPath represents use of a Result plan node to compute the
1408  * output of a degenerate GROUP BY case, wherein we know we should produce
1409  * exactly one row, which might then be filtered by a HAVING qual.
1410  *
1411  * Note that quals is a list of bare clauses, not RestrictInfos.
1412  */
1413 typedef struct GroupResultPath
1414 {
1417 } GroupResultPath;
1418 
1419 /*
1420  * MaterialPath represents use of a Material plan node, i.e., caching of
1421  * the output of its subpath. This is used when the subpath is expensive
1422  * and needs to be scanned repeatedly, or when we need mark/restore ability
1423  * and the subpath doesn't have it.
1424  */
1425 typedef struct MaterialPath
1426 {
1429 } MaterialPath;
1430 
1431 /*
1432  * UniquePath represents elimination of distinct rows from the output of
1433  * its subpath.
1434  *
1435  * This can represent significantly different plans: either hash-based or
1436  * sort-based implementation, or a no-op if the input path can be proven
1437  * distinct already. The decision is sufficiently localized that it's not
1438  * worth having separate Path node types. (Note: in the no-op case, we could
1439  * eliminate the UniquePath node entirely and just return the subpath; but
1440  * it's convenient to have a UniquePath in the path tree to signal upper-level
1441  * routines that the input is known distinct.)
1442  */
1443 typedef enum
1444 {
1445  UNIQUE_PATH_NOOP, /* input is known unique already */
1446  UNIQUE_PATH_HASH, /* use hashing */
1447  UNIQUE_PATH_SORT /* use sorting */
1449 
1450 typedef struct UniquePath
1451 {
1455  List *in_operators; /* equality operators of the IN clause */
1456  List *uniq_exprs; /* expressions to be made unique */
1457 } UniquePath;
1458 
1459 /*
1460  * GatherPath runs several copies of a plan in parallel and collects the
1461  * results. The parallel leader may also execute the plan, unless the
1462  * single_copy flag is set.
1463  */
1464 typedef struct GatherPath
1465 {
1467  Path *subpath; /* path for each worker */
1468  bool single_copy; /* don't execute path more than once */
1469  int num_workers; /* number of workers sought to help */
1470 } GatherPath;
1471 
1472 /*
1473  * GatherMergePath runs several copies of a plan in parallel and collects
1474  * the results, preserving their common sort order.
1475  */
1476 typedef struct GatherMergePath
1477 {
1479  Path *subpath; /* path for each worker */
1480  int num_workers; /* number of workers sought to help */
1481 } GatherMergePath;
1482 
1483 
1484 /*
1485  * All join-type paths share these fields.
1486  */
1487 
1488 typedef struct JoinPath
1489 {
1491 
1493 
1494  bool inner_unique; /* each outer tuple provably matches no more
1495  * than one inner tuple */
1496 
1497  Path *outerjoinpath; /* path for the outer side of the join */
1498  Path *innerjoinpath; /* path for the inner side of the join */
1499 
1500  List *joinrestrictinfo; /* RestrictInfos to apply to join */
1501 
1502  /*
1503  * See the notes for RelOptInfo and ParamPathInfo to understand why
1504  * joinrestrictinfo is needed in JoinPath, and can't be merged into the
1505  * parent RelOptInfo.
1506  */
1507 } JoinPath;
1508 
1509 /*
1510  * A nested-loop path needs no special fields.
1511  */
1512 
1514 
1515 /*
1516  * A mergejoin path has these fields.
1517  *
1518  * Unlike other path types, a MergePath node doesn't represent just a single
1519  * run-time plan node: it can represent up to four. Aside from the MergeJoin
1520  * node itself, there can be a Sort node for the outer input, a Sort node
1521  * for the inner input, and/or a Material node for the inner input. We could
1522  * represent these nodes by separate path nodes, but considering how many
1523  * different merge paths are investigated during a complex join problem,
1524  * it seems better to avoid unnecessary palloc overhead.
1525  *
1526  * path_mergeclauses lists the clauses (in the form of RestrictInfos)
1527  * that will be used in the merge.
1528  *
1529  * Note that the mergeclauses are a subset of the parent relation's
1530  * restriction-clause list. Any join clauses that are not mergejoinable
1531  * appear only in the parent's restrict list, and must be checked by a
1532  * qpqual at execution time.
1533  *
1534  * outersortkeys (resp. innersortkeys) is NIL if the outer path
1535  * (resp. inner path) is already ordered appropriately for the
1536  * mergejoin. If it is not NIL then it is a PathKeys list describing
1537  * the ordering that must be created by an explicit Sort node.
1538  *
1539  * skip_mark_restore is true if the executor need not do mark/restore calls.
1540  * Mark/restore overhead is usually required, but can be skipped if we know
1541  * that the executor need find only one match per outer tuple, and that the
1542  * mergeclauses are sufficient to identify a match. In such cases the
1543  * executor can immediately advance the outer relation after processing a
1544  * match, and therefore it need never back up the inner relation.
1545  *
1546  * materialize_inner is true if a Material node should be placed atop the
1547  * inner input. This may appear with or without an inner Sort step.
1548  */
1549 
1550 typedef struct MergePath
1551 {
1553  List *path_mergeclauses; /* join clauses to be used for merge */
1554  List *outersortkeys; /* keys for explicit sort, if any */
1555  List *innersortkeys; /* keys for explicit sort, if any */
1556  bool skip_mark_restore; /* can executor skip mark/restore? */
1557  bool materialize_inner; /* add Materialize to inner? */
1558 } MergePath;
1559 
1560 /*
1561  * A hashjoin path has these fields.
1562  *
1563  * The remarks above for mergeclauses apply for hashclauses as well.
1564  *
1565  * Hashjoin does not care what order its inputs appear in, so we have
1566  * no need for sortkeys.
1567  */
1568 
1569 typedef struct HashPath
1570 {
1572  List *path_hashclauses; /* join clauses used for hashing */
1573  int num_batches; /* number of batches expected */
1574  double inner_rows_total; /* total inner rows expected */
1575 } HashPath;
1576 
1577 /*
1578  * ProjectionPath represents a projection (that is, targetlist computation)
1579  *
1580  * Nominally, this path node represents using a Result plan node to do a
1581  * projection step. However, if the input plan node supports projection,
1582  * we can just modify its output targetlist to do the required calculations
1583  * directly, and not need a Result. In some places in the planner we can just
1584  * jam the desired PathTarget into the input path node (and adjust its cost
1585  * accordingly), so we don't need a ProjectionPath. But in other places
1586  * it's necessary to not modify the input path node, so we need a separate
1587  * ProjectionPath node, which is marked dummy to indicate that we intend to
1588  * assign the work to the input plan node. The estimated cost for the
1589  * ProjectionPath node will account for whether a Result will be used or not.
1590  */
1591 typedef struct ProjectionPath
1592 {
1594  Path *subpath; /* path representing input source */
1595  bool dummypp; /* true if no separate Result is needed */
1596 } ProjectionPath;
1597 
1598 /*
1599  * ProjectSetPath represents evaluation of a targetlist that includes
1600  * set-returning function(s), which will need to be implemented by a
1601  * ProjectSet plan node.
1602  */
1603 typedef struct ProjectSetPath
1604 {
1606  Path *subpath; /* path representing input source */
1607 } ProjectSetPath;
1608 
1609 /*
1610  * SortPath represents an explicit sort step
1611  *
1612  * The sort keys are, by definition, the same as path.pathkeys.
1613  *
1614  * Note: the Sort plan node cannot project, so path.pathtarget must be the
1615  * same as the input's pathtarget.
1616  */
1617 typedef struct SortPath
1618 {
1620  Path *subpath; /* path representing input source */
1621 } SortPath;
1622 
1623 /*
1624  * GroupPath represents grouping (of presorted input)
1625  *
1626  * groupClause represents the columns to be grouped on; the input path
1627  * must be at least that well sorted.
1628  *
1629  * We can also apply a qual to the grouped rows (equivalent of HAVING)
1630  */
1631 typedef struct GroupPath
1632 {
1634  Path *subpath; /* path representing input source */
1635  List *groupClause; /* a list of SortGroupClause's */
1636  List *qual; /* quals (HAVING quals), if any */
1637 } GroupPath;
1638 
1639 /*
1640  * UpperUniquePath represents adjacent-duplicate removal (in presorted input)
1641  *
1642  * The columns to be compared are the first numkeys columns of the path's
1643  * pathkeys. The input is presumed already sorted that way.
1644  */
1645 typedef struct UpperUniquePath
1646 {
1648  Path *subpath; /* path representing input source */
1649  int numkeys; /* number of pathkey columns to compare */
1650 } UpperUniquePath;
1651 
1652 /*
1653  * AggPath represents generic computation of aggregate functions
1654  *
1655  * This may involve plain grouping (but not grouping sets), using either
1656  * sorted or hashed grouping; for the AGG_SORTED case, the input must be
1657  * appropriately presorted.
1658  */
1659 typedef struct AggPath
1660 {
1662  Path *subpath; /* path representing input source */
1663  AggStrategy aggstrategy; /* basic strategy, see nodes.h */
1664  AggSplit aggsplit; /* agg-splitting mode, see nodes.h */
1665  double numGroups; /* estimated number of groups in input */
1666  List *groupClause; /* a list of SortGroupClause's */
1667  List *qual; /* quals (HAVING quals), if any */
1668 } AggPath;
1669 
1670 /*
1671  * Various annotations used for grouping sets in the planner.
1672  */
1673 
1674 typedef struct GroupingSetData
1675 {
1677  List *set; /* grouping set as list of sortgrouprefs */
1678  double numGroups; /* est. number of result groups */
1679 } GroupingSetData;
1680 
1681 typedef struct RollupData
1682 {
1684  List *groupClause; /* applicable subset of parse->groupClause */
1685  List *gsets; /* lists of integer indexes into groupClause */
1686  List *gsets_data; /* list of GroupingSetData */
1687  double numGroups; /* est. number of result groups */
1688  bool hashable; /* can be hashed */
1689  bool is_hashed; /* to be implemented as a hashagg */
1690 } RollupData;
1691 
1692 /*
1693  * GroupingSetsPath represents a GROUPING SETS aggregation
1694  */
1695 
1696 typedef struct GroupingSetsPath
1697 {
1699  Path *subpath; /* path representing input source */
1700  AggStrategy aggstrategy; /* basic strategy */
1701  List *rollups; /* list of RollupData */
1702  List *qual; /* quals (HAVING quals), if any */
1704 
1705 /*
1706  * MinMaxAggPath represents computation of MIN/MAX aggregates from indexes
1707  */
1708 typedef struct MinMaxAggPath
1709 {
1711  List *mmaggregates; /* list of MinMaxAggInfo */
1712  List *quals; /* HAVING quals, if any */
1713 } MinMaxAggPath;
1714 
1715 /*
1716  * WindowAggPath represents generic computation of window functions
1717  */
1718 typedef struct WindowAggPath
1719 {
1721  Path *subpath; /* path representing input source */
1722  WindowClause *winclause; /* WindowClause we'll be using */
1723 } WindowAggPath;
1724 
1725 /*
1726  * SetOpPath represents a set-operation, that is INTERSECT or EXCEPT
1727  */
1728 typedef struct SetOpPath
1729 {
1731  Path *subpath; /* path representing input source */
1732  SetOpCmd cmd; /* what to do, see nodes.h */
1733  SetOpStrategy strategy; /* how to do it, see nodes.h */
1734  List *distinctList; /* SortGroupClauses identifying target cols */
1735  AttrNumber flagColIdx; /* where is the flag column, if any */
1736  int firstFlag; /* flag value for first input relation */
1737  double numGroups; /* estimated number of groups in input */
1738 } SetOpPath;
1739 
1740 /*
1741  * RecursiveUnionPath represents a recursive UNION node
1742  */
1743 typedef struct RecursiveUnionPath
1744 {
1746  Path *leftpath; /* paths representing input sources */
1748  List *distinctList; /* SortGroupClauses identifying target cols */
1749  int wtParam; /* ID of Param representing work table */
1750  double numGroups; /* estimated number of groups in input */
1752 
1753 /*
1754  * LockRowsPath represents acquiring row locks for SELECT FOR UPDATE/SHARE
1755  */
1756 typedef struct LockRowsPath
1757 {
1759  Path *subpath; /* path representing input source */
1760  List *rowMarks; /* a list of PlanRowMark's */
1761  int epqParam; /* ID of Param for EvalPlanQual re-eval */
1762 } LockRowsPath;
1763 
1764 /*
1765  * ModifyTablePath represents performing INSERT/UPDATE/DELETE modifications
1766  *
1767  * We represent most things that will be in the ModifyTable plan node
1768  * literally, except we have child Path(s) not Plan(s). But analysis of the
1769  * OnConflictExpr is deferred to createplan.c, as is collection of FDW data.
1770  */
1771 typedef struct ModifyTablePath
1772 {
1774  CmdType operation; /* INSERT, UPDATE, or DELETE */
1775  bool canSetTag; /* do we set the command tag/es_processed? */
1776  Index nominalRelation; /* Parent RT index for use of EXPLAIN */
1777  Index rootRelation; /* Root RT index, if target is partitioned */
1778  bool partColsUpdated; /* some part key in hierarchy updated */
1779  List *resultRelations; /* integer list of RT indexes */
1780  List *subpaths; /* Path(s) producing source data */
1781  List *subroots; /* per-target-table PlannerInfos */
1782  List *withCheckOptionLists; /* per-target-table WCO lists */
1783  List *returningLists; /* per-target-table RETURNING tlists */
1784  List *rowMarks; /* PlanRowMarks (non-locking only) */
1785  OnConflictExpr *onconflict; /* ON CONFLICT clause, or NULL */
1786  int epqParam; /* ID of Param for EvalPlanQual re-eval */
1787 } ModifyTablePath;
1788 
1789 /*
1790  * LimitPath represents applying LIMIT/OFFSET restrictions
1791  */
1792 typedef struct LimitPath
1793 {
1795  Path *subpath; /* path representing input source */
1796  Node *limitOffset; /* OFFSET parameter, or NULL if none */
1797  Node *limitCount; /* COUNT parameter, or NULL if none */
1798 } LimitPath;
1799 
1800 
1801 /*
1802  * Restriction clause info.
1803  *
1804  * We create one of these for each AND sub-clause of a restriction condition
1805  * (WHERE or JOIN/ON clause). Since the restriction clauses are logically
1806  * ANDed, we can use any one of them or any subset of them to filter out
1807  * tuples, without having to evaluate the rest. The RestrictInfo node itself
1808  * stores data used by the optimizer while choosing the best query plan.
1809  *
1810  * If a restriction clause references a single base relation, it will appear
1811  * in the baserestrictinfo list of the RelOptInfo for that base rel.
1812  *
1813  * If a restriction clause references more than one base rel, it will
1814  * appear in the joininfo list of every RelOptInfo that describes a strict
1815  * subset of the base rels mentioned in the clause. The joininfo lists are
1816  * used to drive join tree building by selecting plausible join candidates.
1817  * The clause cannot actually be applied until we have built a join rel
1818  * containing all the base rels it references, however.
1819  *
1820  * When we construct a join rel that includes all the base rels referenced
1821  * in a multi-relation restriction clause, we place that clause into the
1822  * joinrestrictinfo lists of paths for the join rel, if neither left nor
1823  * right sub-path includes all base rels referenced in the clause. The clause
1824  * will be applied at that join level, and will not propagate any further up
1825  * the join tree. (Note: the "predicate migration" code was once intended to
1826  * push restriction clauses up and down the plan tree based on evaluation
1827  * costs, but it's dead code and is unlikely to be resurrected in the
1828  * foreseeable future.)
1829  *
1830  * Note that in the presence of more than two rels, a multi-rel restriction
1831  * might reach different heights in the join tree depending on the join
1832  * sequence we use. So, these clauses cannot be associated directly with
1833  * the join RelOptInfo, but must be kept track of on a per-join-path basis.
1834  *
1835  * RestrictInfos that represent equivalence conditions (i.e., mergejoinable
1836  * equalities that are not outerjoin-delayed) are handled a bit differently.
1837  * Initially we attach them to the EquivalenceClasses that are derived from
1838  * them. When we construct a scan or join path, we look through all the
1839  * EquivalenceClasses and generate derived RestrictInfos representing the
1840  * minimal set of conditions that need to be checked for this particular scan
1841  * or join to enforce that all members of each EquivalenceClass are in fact
1842  * equal in all rows emitted by the scan or join.
1843  *
1844  * When dealing with outer joins we have to be very careful about pushing qual
1845  * clauses up and down the tree. An outer join's own JOIN/ON conditions must
1846  * be evaluated exactly at that join node, unless they are "degenerate"
1847  * conditions that reference only Vars from the nullable side of the join.
1848  * Quals appearing in WHERE or in a JOIN above the outer join cannot be pushed
1849  * down below the outer join, if they reference any nullable Vars.
1850  * RestrictInfo nodes contain a flag to indicate whether a qual has been
1851  * pushed down to a lower level than its original syntactic placement in the
1852  * join tree would suggest. If an outer join prevents us from pushing a qual
1853  * down to its "natural" semantic level (the level associated with just the
1854  * base rels used in the qual) then we mark the qual with a "required_relids"
1855  * value including more than just the base rels it actually uses. By
1856  * pretending that the qual references all the rels required to form the outer
1857  * join, we prevent it from being evaluated below the outer join's joinrel.
1858  * When we do form the outer join's joinrel, we still need to distinguish
1859  * those quals that are actually in that join's JOIN/ON condition from those
1860  * that appeared elsewhere in the tree and were pushed down to the join rel
1861  * because they used no other rels. That's what the is_pushed_down flag is
1862  * for; it tells us that a qual is not an OUTER JOIN qual for the set of base
1863  * rels listed in required_relids. A clause that originally came from WHERE
1864  * or an INNER JOIN condition will *always* have its is_pushed_down flag set.
1865  * It's possible for an OUTER JOIN clause to be marked is_pushed_down too,
1866  * if we decide that it can be pushed down into the nullable side of the join.
1867  * In that case it acts as a plain filter qual for wherever it gets evaluated.
1868  * (In short, is_pushed_down is only false for non-degenerate outer join
1869  * conditions. Possibly we should rename it to reflect that meaning? But
1870  * see also the comments for RINFO_IS_PUSHED_DOWN, below.)
1871  *
1872  * RestrictInfo nodes also contain an outerjoin_delayed flag, which is true
1873  * if the clause's applicability must be delayed due to any outer joins
1874  * appearing below it (ie, it has to be postponed to some join level higher
1875  * than the set of relations it actually references).
1876  *
1877  * There is also an outer_relids field, which is NULL except for outer join
1878  * clauses; for those, it is the set of relids on the outer side of the
1879  * clause's outer join. (These are rels that the clause cannot be applied to
1880  * in parameterized scans, since pushing it into the join's outer side would
1881  * lead to wrong answers.)
1882  *
1883  * There is also a nullable_relids field, which is the set of rels the clause
1884  * references that can be forced null by some outer join below the clause.
1885  *
1886  * outerjoin_delayed = true is subtly different from nullable_relids != NULL:
1887  * a clause might reference some nullable rels and yet not be
1888  * outerjoin_delayed because it also references all the other rels of the
1889  * outer join(s). A clause that is not outerjoin_delayed can be enforced
1890  * anywhere it is computable.
1891  *
1892  * To handle security-barrier conditions efficiently, we mark RestrictInfo
1893  * nodes with a security_level field, in which higher values identify clauses
1894  * coming from less-trusted sources. The exact semantics are that a clause
1895  * cannot be evaluated before another clause with a lower security_level value
1896  * unless the first clause is leakproof. As with outer-join clauses, this
1897  * creates a reason for clauses to sometimes need to be evaluated higher in
1898  * the join tree than their contents would suggest; and even at a single plan
1899  * node, this rule constrains the order of application of clauses.
1900  *
1901  * In general, the referenced clause might be arbitrarily complex. The
1902  * kinds of clauses we can handle as indexscan quals, mergejoin clauses,
1903  * or hashjoin clauses are limited (e.g., no volatile functions). The code
1904  * for each kind of path is responsible for identifying the restrict clauses
1905  * it can use and ignoring the rest. Clauses not implemented by an indexscan,
1906  * mergejoin, or hashjoin will be placed in the plan qual or joinqual field
1907  * of the finished Plan node, where they will be enforced by general-purpose
1908  * qual-expression-evaluation code. (But we are still entitled to count
1909  * their selectivity when estimating the result tuple count, if we
1910  * can guess what it is...)
1911  *
1912  * When the referenced clause is an OR clause, we generate a modified copy
1913  * in which additional RestrictInfo nodes are inserted below the top-level
1914  * OR/AND structure. This is a convenience for OR indexscan processing:
1915  * indexquals taken from either the top level or an OR subclause will have
1916  * associated RestrictInfo nodes.
1917  *
1918  * The can_join flag is set true if the clause looks potentially useful as
1919  * a merge or hash join clause, that is if it is a binary opclause with
1920  * nonoverlapping sets of relids referenced in the left and right sides.
1921  * (Whether the operator is actually merge or hash joinable isn't checked,
1922  * however.)
1923  *
1924  * The pseudoconstant flag is set true if the clause contains no Vars of
1925  * the current query level and no volatile functions. Such a clause can be
1926  * pulled out and used as a one-time qual in a gating Result node. We keep
1927  * pseudoconstant clauses in the same lists as other RestrictInfos so that
1928  * the regular clause-pushing machinery can assign them to the correct join
1929  * level, but they need to be treated specially for cost and selectivity
1930  * estimates. Note that a pseudoconstant clause can never be an indexqual
1931  * or merge or hash join clause, so it's of no interest to large parts of
1932  * the planner.
1933  *
1934  * When join clauses are generated from EquivalenceClasses, there may be
1935  * several equally valid ways to enforce join equivalence, of which we need
1936  * apply only one. We mark clauses of this kind by setting parent_ec to
1937  * point to the generating EquivalenceClass. Multiple clauses with the same
1938  * parent_ec in the same join are redundant.
1939  */
1940 
1941 typedef struct RestrictInfo
1942 {
1944 
1945  Expr *clause; /* the represented clause of WHERE or JOIN */
1946 
1947  bool is_pushed_down; /* true if clause was pushed down in level */
1948 
1949  bool outerjoin_delayed; /* true if delayed by lower outer join */
1950 
1951  bool can_join; /* see comment above */
1952 
1953  bool pseudoconstant; /* see comment above */
1954 
1955  bool leakproof; /* true if known to contain no leaked Vars */
1956 
1957  Index security_level; /* see comment above */
1958 
1959  /* The set of relids (varnos) actually referenced in the clause: */
1961 
1962  /* The set of relids required to evaluate the clause: */
1964 
1965  /* If an outer-join clause, the outer-side relations, else NULL: */
1967 
1968  /* The relids used in the clause that are nullable by lower outer joins: */
1970 
1971  /* These fields are set for any binary opclause: */
1972  Relids left_relids; /* relids in left side of clause */
1973  Relids right_relids; /* relids in right side of clause */
1974 
1975  /* This field is NULL unless clause is an OR clause: */
1976  Expr *orclause; /* modified clause with RestrictInfos */
1977 
1978  /* This field is NULL unless clause is potentially redundant: */
1979  EquivalenceClass *parent_ec; /* generating EquivalenceClass */
1980 
1981  /* cache space for cost and selectivity */
1982  QualCost eval_cost; /* eval cost of clause; -1 if not yet set */
1983  Selectivity norm_selec; /* selectivity for "normal" (JOIN_INNER)
1984  * semantics; -1 if not yet set; >1 means a
1985  * redundant clause */
1986  Selectivity outer_selec; /* selectivity for outer join semantics; -1 if
1987  * not yet set */
1988 
1989  /* valid if clause is mergejoinable, else NIL */
1990  List *mergeopfamilies; /* opfamilies containing clause operator */
1991 
1992  /* cache space for mergeclause processing; NULL if not yet set */
1993  EquivalenceClass *left_ec; /* EquivalenceClass containing lefthand */
1994  EquivalenceClass *right_ec; /* EquivalenceClass containing righthand */
1995  EquivalenceMember *left_em; /* EquivalenceMember for lefthand */
1996  EquivalenceMember *right_em; /* EquivalenceMember for righthand */
1997  List *scansel_cache; /* list of MergeScanSelCache structs */
1998 
1999  /* transient workspace for use while considering a specific join path */
2000  bool outer_is_left; /* T = outer var on left, F = on right */
2001 
2002  /* valid if clause is hashjoinable, else InvalidOid: */
2003  Oid hashjoinoperator; /* copy of clause operator */
2004 
2005  /* cache space for hashclause processing; -1 if not yet set */
2006  Selectivity left_bucketsize; /* avg bucketsize of left side */
2007  Selectivity right_bucketsize; /* avg bucketsize of right side */
2008  Selectivity left_mcvfreq; /* left side's most common val's freq */
2009  Selectivity right_mcvfreq; /* right side's most common val's freq */
2010 } RestrictInfo;
2011 
2012 /*
2013  * This macro embodies the correct way to test whether a RestrictInfo is
2014  * "pushed down" to a given outer join, that is, should be treated as a filter
2015  * clause rather than a join clause at that outer join. This is certainly so
2016  * if is_pushed_down is true; but examining that is not sufficient anymore,
2017  * because outer-join clauses will get pushed down to lower outer joins when
2018  * we generate a path for the lower outer join that is parameterized by the
2019  * LHS of the upper one. We can detect such a clause by noting that its
2020  * required_relids exceed the scope of the join.
2021  */
2022 #define RINFO_IS_PUSHED_DOWN(rinfo, joinrelids) \
2023  ((rinfo)->is_pushed_down || \
2024  !bms_is_subset((rinfo)->required_relids, joinrelids))
2025 
2026 /*
2027  * Since mergejoinscansel() is a relatively expensive function, and would
2028  * otherwise be invoked many times while planning a large join tree,
2029  * we go out of our way to cache its results. Each mergejoinable
2030  * RestrictInfo carries a list of the specific sort orderings that have
2031  * been considered for use with it, and the resulting selectivities.
2032  */
2033 typedef struct MergeScanSelCache
2034 {
2035  /* Ordering details (cache lookup key) */
2036  Oid opfamily; /* btree opfamily defining the ordering */
2037  Oid collation; /* collation for the ordering */
2038  int strategy; /* sort direction (ASC or DESC) */
2039  bool nulls_first; /* do NULLs come before normal values? */
2040  /* Results */
2041  Selectivity leftstartsel; /* first-join fraction for clause left side */
2042  Selectivity leftendsel; /* last-join fraction for clause left side */
2043  Selectivity rightstartsel; /* first-join fraction for clause right side */
2044  Selectivity rightendsel; /* last-join fraction for clause right side */
2046 
2047 /*
2048  * Placeholder node for an expression to be evaluated below the top level
2049  * of a plan tree. This is used during planning to represent the contained
2050  * expression. At the end of the planning process it is replaced by either
2051  * the contained expression or a Var referring to a lower-level evaluation of
2052  * the contained expression. Typically the evaluation occurs below an outer
2053  * join, and Var references above the outer join might thereby yield NULL
2054  * instead of the expression value.
2055  *
2056  * Although the planner treats this as an expression node type, it is not
2057  * recognized by the parser or executor, so we declare it here rather than
2058  * in primnodes.h.
2059  */
2060 
2061 typedef struct PlaceHolderVar
2062 {
2064  Expr *phexpr; /* the represented expression */
2065  Relids phrels; /* base relids syntactically within expr src */
2066  Index phid; /* ID for PHV (unique within planner run) */
2067  Index phlevelsup; /* > 0 if PHV belongs to outer query */
2068 } PlaceHolderVar;
2069 
2070 /*
2071  * "Special join" info.
2072  *
2073  * One-sided outer joins constrain the order of joining partially but not
2074  * completely. We flatten such joins into the planner's top-level list of
2075  * relations to join, but record information about each outer join in a
2076  * SpecialJoinInfo struct. These structs are kept in the PlannerInfo node's
2077  * join_info_list.
2078  *
2079  * Similarly, semijoins and antijoins created by flattening IN (subselect)
2080  * and EXISTS(subselect) clauses create partial constraints on join order.
2081  * These are likewise recorded in SpecialJoinInfo structs.
2082  *
2083  * We make SpecialJoinInfos for FULL JOINs even though there is no flexibility
2084  * of planning for them, because this simplifies make_join_rel()'s API.
2085  *
2086  * min_lefthand and min_righthand are the sets of base relids that must be
2087  * available on each side when performing the special join. lhs_strict is
2088  * true if the special join's condition cannot succeed when the LHS variables
2089  * are all NULL (this means that an outer join can commute with upper-level
2090  * outer joins even if it appears in their RHS). We don't bother to set
2091  * lhs_strict for FULL JOINs, however.
2092  *
2093  * It is not valid for either min_lefthand or min_righthand to be empty sets;
2094  * if they were, this would break the logic that enforces join order.
2095  *
2096  * syn_lefthand and syn_righthand are the sets of base relids that are
2097  * syntactically below this special join. (These are needed to help compute
2098  * min_lefthand and min_righthand for higher joins.)
2099  *
2100  * delay_upper_joins is set true if we detect a pushed-down clause that has
2101  * to be evaluated after this join is formed (because it references the RHS).
2102  * Any outer joins that have such a clause and this join in their RHS cannot
2103  * commute with this join, because that would leave noplace to check the
2104  * pushed-down clause. (We don't track this for FULL JOINs, either.)
2105  *
2106  * For a semijoin, we also extract the join operators and their RHS arguments
2107  * and set semi_operators, semi_rhs_exprs, semi_can_btree, and semi_can_hash.
2108  * This is done in support of possibly unique-ifying the RHS, so we don't
2109  * bother unless at least one of semi_can_btree and semi_can_hash can be set
2110  * true. (You might expect that this information would be computed during
2111  * join planning; but it's helpful to have it available during planning of
2112  * parameterized table scans, so we store it in the SpecialJoinInfo structs.)
2113  *
2114  * jointype is never JOIN_RIGHT; a RIGHT JOIN is handled by switching
2115  * the inputs to make it a LEFT JOIN. So the allowed values of jointype
2116  * in a join_info_list member are only LEFT, FULL, SEMI, or ANTI.
2117  *
2118  * For purposes of join selectivity estimation, we create transient
2119  * SpecialJoinInfo structures for regular inner joins; so it is possible
2120  * to have jointype == JOIN_INNER in such a structure, even though this is
2121  * not allowed within join_info_list. We also create transient
2122  * SpecialJoinInfos with jointype == JOIN_INNER for outer joins, since for
2123  * cost estimation purposes it is sometimes useful to know the join size under
2124  * plain innerjoin semantics. Note that lhs_strict, delay_upper_joins, and
2125  * of course the semi_xxx fields are not set meaningfully within such structs.
2126  */
2127 #ifndef HAVE_SPECIALJOININFO_TYPEDEF
2129 #define HAVE_SPECIALJOININFO_TYPEDEF 1
2130 #endif
2131 
2133 {
2135  Relids min_lefthand; /* base relids in minimum LHS for join */
2136  Relids min_righthand; /* base relids in minimum RHS for join */
2137  Relids syn_lefthand; /* base relids syntactically within LHS */
2138  Relids syn_righthand; /* base relids syntactically within RHS */
2139  JoinType jointype; /* always INNER, LEFT, FULL, SEMI, or ANTI */
2140  bool lhs_strict; /* joinclause is strict for some LHS rel */
2141  bool delay_upper_joins; /* can't commute with upper RHS */
2142  /* Remaining fields are set only for JOIN_SEMI jointype: */
2143  bool semi_can_btree; /* true if semi_operators are all btree */
2144  bool semi_can_hash; /* true if semi_operators are all hash */
2145  List *semi_operators; /* OIDs of equality join operators */
2146  List *semi_rhs_exprs; /* righthand-side expressions of these ops */
2147 };
2148 
2149 /*
2150  * Append-relation info.
2151  *
2152  * When we expand an inheritable table or a UNION-ALL subselect into an
2153  * "append relation" (essentially, a list of child RTEs), we build an
2154  * AppendRelInfo for each child RTE. The list of AppendRelInfos indicates
2155  * which child RTEs must be included when expanding the parent, and each node
2156  * carries information needed to translate between columns of the parent and
2157  * columns of the child.
2158  *
2159  * These structs are kept in the PlannerInfo node's append_rel_list, with
2160  * append_rel_array[] providing a convenient lookup method for the struct
2161  * associated with a particular child relid (there can be only one, though
2162  * parent rels may have many entries in append_rel_list).
2163  *
2164  * Note: after completion of the planner prep phase, any given RTE is an
2165  * append parent having entries in append_rel_list if and only if its
2166  * "inh" flag is set. We clear "inh" for plain tables that turn out not
2167  * to have inheritance children, and (in an abuse of the original meaning
2168  * of the flag) we set "inh" for subquery RTEs that turn out to be
2169  * flattenable UNION ALL queries. This lets us avoid useless searches
2170  * of append_rel_list.
2171  *
2172  * Note: the data structure assumes that append-rel members are single
2173  * baserels. This is OK for inheritance, but it prevents us from pulling
2174  * up a UNION ALL member subquery if it contains a join. While that could
2175  * be fixed with a more complex data structure, at present there's not much
2176  * point because no improvement in the plan could result.
2177  */
2178 
2179 typedef struct AppendRelInfo
2180 {
2182 
2183  /*
2184  * These fields uniquely identify this append relationship. There can be
2185  * (in fact, always should be) multiple AppendRelInfos for the same
2186  * parent_relid, but never more than one per child_relid, since a given
2187  * RTE cannot be a child of more than one append parent.
2188  */
2189  Index parent_relid; /* RT index of append parent rel */
2190  Index child_relid; /* RT index of append child rel */
2191 
2192  /*
2193  * For an inheritance appendrel, the parent and child are both regular
2194  * relations, and we store their rowtype OIDs here for use in translating
2195  * whole-row Vars. For a UNION-ALL appendrel, the parent and child are
2196  * both subqueries with no named rowtype, and we store InvalidOid here.
2197  */
2198  Oid parent_reltype; /* OID of parent's composite type */
2199  Oid child_reltype; /* OID of child's composite type */
2200 
2201  /*
2202  * The N'th element of this list is a Var or expression representing the
2203  * child column corresponding to the N'th column of the parent. This is
2204  * used to translate Vars referencing the parent rel into references to
2205  * the child. A list element is NULL if it corresponds to a dropped
2206  * column of the parent (this is only possible for inheritance cases, not
2207  * UNION ALL). The list elements are always simple Vars for inheritance
2208  * cases, but can be arbitrary expressions in UNION ALL cases.
2209  *
2210  * Notice we only store entries for user columns (attno > 0). Whole-row
2211  * Vars are special-cased, and system columns (attno < 0) need no special
2212  * translation since their attnos are the same for all tables.
2213  *
2214  * Caution: the Vars have varlevelsup = 0. Be careful to adjust as needed
2215  * when copying into a subquery.
2216  */
2217  List *translated_vars; /* Expressions in the child's Vars */
2218 
2219  /*
2220  * This array simplifies translations in the reverse direction, from
2221  * child's column numbers to parent's. The entry at [ccolno - 1] is the
2222  * 1-based parent column number for child column ccolno, or zero if that
2223  * child column is dropped or doesn't exist in the parent.
2224  */
2225  int num_child_cols; /* length of array */
2226  AttrNumber *parent_colnos; /* array of parent attnos, or zeroes */
2227 
2228  /*
2229  * We store the parent table's OID here for inheritance, or InvalidOid for
2230  * UNION ALL. This is only needed to help in generating error messages if
2231  * an attempt is made to reference a dropped parent column.
2232  */
2233  Oid parent_reloid; /* OID of parent relation */
2234 } AppendRelInfo;
2235 
2236 /*
2237  * For each distinct placeholder expression generated during planning, we
2238  * store a PlaceHolderInfo node in the PlannerInfo node's placeholder_list.
2239  * This stores info that is needed centrally rather than in each copy of the
2240  * PlaceHolderVar. The phid fields identify which PlaceHolderInfo goes with
2241  * each PlaceHolderVar. Note that phid is unique throughout a planner run,
2242  * not just within a query level --- this is so that we need not reassign ID's
2243  * when pulling a subquery into its parent.
2244  *
2245  * The idea is to evaluate the expression at (only) the ph_eval_at join level,
2246  * then allow it to bubble up like a Var until the ph_needed join level.
2247  * ph_needed has the same definition as attr_needed for a regular Var.
2248  *
2249  * The PlaceHolderVar's expression might contain LATERAL references to vars
2250  * coming from outside its syntactic scope. If so, those rels are *not*
2251  * included in ph_eval_at, but they are recorded in ph_lateral.
2252  *
2253  * Notice that when ph_eval_at is a join rather than a single baserel, the
2254  * PlaceHolderInfo may create constraints on join order: the ph_eval_at join
2255  * has to be formed below any outer joins that should null the PlaceHolderVar.
2256  *
2257  * We create a PlaceHolderInfo only after determining that the PlaceHolderVar
2258  * is actually referenced in the plan tree, so that unreferenced placeholders
2259  * don't result in unnecessary constraints on join order.
2260  */
2261 
2262 typedef struct PlaceHolderInfo
2263 {
2265 
2266  Index phid; /* ID for PH (unique within planner run) */
2267  PlaceHolderVar *ph_var; /* copy of PlaceHolderVar tree */
2268  Relids ph_eval_at; /* lowest level we can evaluate value at */
2269  Relids ph_lateral; /* relids of contained lateral refs, if any */
2270  Relids ph_needed; /* highest level the value is needed at */
2271  int32 ph_width; /* estimated attribute width */
2272 } PlaceHolderInfo;
2273 
2274 /*
2275  * This struct describes one potentially index-optimizable MIN/MAX aggregate
2276  * function. MinMaxAggPath contains a list of these, and if we accept that
2277  * path, the list is stored into root->minmax_aggs for use during setrefs.c.
2278  */
2279 typedef struct MinMaxAggInfo
2280 {
2282 
2283  Oid aggfnoid; /* pg_proc Oid of the aggregate */
2284  Oid aggsortop; /* Oid of its sort operator */
2285  Expr *target; /* expression we are aggregating on */
2286  PlannerInfo *subroot; /* modified "root" for planning the subquery */
2287  Path *path; /* access path for subquery */
2288  Cost pathcost; /* estimated cost to fetch first row */
2289  Param *param; /* param for subplan's output */
2290 } MinMaxAggInfo;
2291 
2292 /*
2293  * At runtime, PARAM_EXEC slots are used to pass values around from one plan
2294  * node to another. They can be used to pass values down into subqueries (for
2295  * outer references in subqueries), or up out of subqueries (for the results
2296  * of a subplan), or from a NestLoop plan node into its inner relation (when
2297  * the inner scan is parameterized with values from the outer relation).
2298  * The planner is responsible for assigning nonconflicting PARAM_EXEC IDs to
2299  * the PARAM_EXEC Params it generates.
2300  *
2301  * Outer references are managed via root->plan_params, which is a list of
2302  * PlannerParamItems. While planning a subquery, each parent query level's
2303  * plan_params contains the values required from it by the current subquery.
2304  * During create_plan(), we use plan_params to track values that must be
2305  * passed from outer to inner sides of NestLoop plan nodes.
2306  *
2307  * The item a PlannerParamItem represents can be one of three kinds:
2308  *
2309  * A Var: the slot represents a variable of this level that must be passed
2310  * down because subqueries have outer references to it, or must be passed
2311  * from a NestLoop node to its inner scan. The varlevelsup value in the Var
2312  * will always be zero.
2313  *
2314  * A PlaceHolderVar: this works much like the Var case, except that the
2315  * entry is a PlaceHolderVar node with a contained expression. The PHV
2316  * will have phlevelsup = 0, and the contained expression is adjusted
2317  * to match in level.
2318  *
2319  * An Aggref (with an expression tree representing its argument): the slot
2320  * represents an aggregate expression that is an outer reference for some
2321  * subquery. The Aggref itself has agglevelsup = 0, and its argument tree
2322  * is adjusted to match in level.
2323  *
2324  * Note: we detect duplicate Var and PlaceHolderVar parameters and coalesce
2325  * them into one slot, but we do not bother to do that for Aggrefs.
2326  * The scope of duplicate-elimination only extends across the set of
2327  * parameters passed from one query level into a single subquery, or for
2328  * nestloop parameters across the set of nestloop parameters used in a single
2329  * query level. So there is no possibility of a PARAM_EXEC slot being used
2330  * for conflicting purposes.
2331  *
2332  * In addition, PARAM_EXEC slots are assigned for Params representing outputs
2333  * from subplans (values that are setParam items for those subplans). These
2334  * IDs need not be tracked via PlannerParamItems, since we do not need any
2335  * duplicate-elimination nor later processing of the represented expressions.
2336  * Instead, we just record the assignment of the slot number by appending to
2337  * root->glob->paramExecTypes.
2338  */
2339 typedef struct PlannerParamItem
2340 {
2342 
2343  Node *item; /* the Var, PlaceHolderVar, or Aggref */
2344  int paramId; /* its assigned PARAM_EXEC slot number */
2346 
2347 /*
2348  * When making cost estimates for a SEMI/ANTI/inner_unique join, there are
2349  * some correction factors that are needed in both nestloop and hash joins
2350  * to account for the fact that the executor can stop scanning inner rows
2351  * as soon as it finds a match to the current outer row. These numbers
2352  * depend only on the selected outer and inner join relations, not on the
2353  * particular paths used for them, so it's worthwhile to calculate them
2354  * just once per relation pair not once per considered path. This struct
2355  * is filled by compute_semi_anti_join_factors and must be passed along
2356  * to the join cost estimation functions.
2357  *
2358  * outer_match_frac is the fraction of the outer tuples that are
2359  * expected to have at least one match.
2360  * match_count is the average number of matches expected for
2361  * outer tuples that have at least one match.
2362  */
2363 typedef struct SemiAntiJoinFactors
2364 {
2368 
2369 /*
2370  * Struct for extra information passed to subroutines of add_paths_to_joinrel
2371  *
2372  * restrictlist contains all of the RestrictInfo nodes for restriction
2373  * clauses that apply to this join
2374  * mergeclause_list is a list of RestrictInfo nodes for available
2375  * mergejoin clauses in this join
2376  * inner_unique is true if each outer tuple provably matches no more
2377  * than one inner tuple
2378  * sjinfo is extra info about special joins for selectivity estimation
2379  * semifactors is as shown above (only valid for SEMI/ANTI/inner_unique joins)
2380  * param_source_rels are OK targets for parameterization of result paths
2381  */
2382 typedef struct JoinPathExtraData
2383 {
2391 
2392 /*
2393  * Various flags indicating what kinds of grouping are possible.
2394  *
2395  * GROUPING_CAN_USE_SORT should be set if it's possible to perform
2396  * sort-based implementations of grouping. When grouping sets are in use,
2397  * this will be true if sorting is potentially usable for any of the grouping
2398  * sets, even if it's not usable for all of them.
2399  *
2400  * GROUPING_CAN_USE_HASH should be set if it's possible to perform
2401  * hash-based implementations of grouping.
2402  *
2403  * GROUPING_CAN_PARTIAL_AGG should be set if the aggregation is of a type
2404  * for which we support partial aggregation (not, for example, grouping sets).
2405  * It says nothing about parallel-safety or the availability of suitable paths.
2406  */
2407 #define GROUPING_CAN_USE_SORT 0x0001
2408 #define GROUPING_CAN_USE_HASH 0x0002
2409 #define GROUPING_CAN_PARTIAL_AGG 0x0004
2410 
2411 /*
2412  * What kind of partitionwise aggregation is in use?
2413  *
2414  * PARTITIONWISE_AGGREGATE_NONE: Not used.
2415  *
2416  * PARTITIONWISE_AGGREGATE_FULL: Aggregate each partition separately, and
2417  * append the results.
2418  *
2419  * PARTITIONWISE_AGGREGATE_PARTIAL: Partially aggregate each partition
2420  * separately, append the results, and then finalize aggregation.
2421  */
2422 typedef enum
2423 {
2428 
2429 /*
2430  * Struct for extra information passed to subroutines of create_grouping_paths
2431  *
2432  * flags indicating what kinds of grouping are possible.
2433  * partial_costs_set is true if the agg_partial_costs and agg_final_costs
2434  * have been initialized.
2435  * agg_partial_costs gives partial aggregation costs.
2436  * agg_final_costs gives finalization costs.
2437  * target_parallel_safe is true if target is parallel safe.
2438  * havingQual gives list of quals to be applied after aggregation.
2439  * targetList gives list of columns to be projected.
2440  * patype is the type of partitionwise aggregation that is being performed.
2441  */
2442 typedef struct
2443 {
2444  /* Data which remains constant once set. */
2445  int flags;
2449 
2450  /* Data which may differ across partitions. */
2456 
2457 /*
2458  * Struct for extra information passed to subroutines of grouping_planner
2459  *
2460  * limit_needed is true if we actually need a Limit plan node.
2461  * limit_tuples is an estimated bound on the number of output tuples,
2462  * or -1 if no LIMIT or couldn't estimate.
2463  * count_est and offset_est are the estimated values of the LIMIT and OFFSET
2464  * expressions computed by preprocess_limit() (see comments for
2465  * preprocess_limit() for more information).
2466  */
2467 typedef struct
2468 {
2471  int64 count_est;
2472  int64 offset_est;
2474 
2475 /*
2476  * For speed reasons, cost estimation for join paths is performed in two
2477  * phases: the first phase tries to quickly derive a lower bound for the
2478  * join cost, and then we check if that's sufficient to reject the path.
2479  * If not, we come back for a more refined cost estimate. The first phase
2480  * fills a JoinCostWorkspace struct with its preliminary cost estimates
2481  * and possibly additional intermediate values. The second phase takes
2482  * these values as inputs to avoid repeating work.
2483  *
2484  * (Ideally we'd declare this in cost.h, but it's also needed in pathnode.h,
2485  * so seems best to put it here.)
2486  */
2487 typedef struct JoinCostWorkspace
2488 {
2489  /* Preliminary cost estimates --- must not be larger than final ones! */
2490  Cost startup_cost; /* cost expended before fetching any tuples */
2491  Cost total_cost; /* total cost (assuming all tuples fetched) */
2492 
2493  /* Fields below here should be treated as private to costsize.c */
2494  Cost run_cost; /* non-startup cost components */
2495 
2496  /* private for cost_nestloop code */
2497  Cost inner_run_cost; /* also used by cost_mergejoin code */
2499 
2500  /* private for cost_mergejoin code */
2501  double outer_rows;
2502  double inner_rows;
2505 
2506  /* private for cost_hashjoin code */
2511 
2512 #endif /* PATHNODES_H */
QualCost eval_cost
Definition: pathnodes.h:1982
bool has_eclass_joins
Definition: pathnodes.h:711
struct TidPath TidPath
struct Path * cheapest_unique_path
Definition: pathnodes.h:662
NodeTag type
Definition: pathnodes.h:1683
List * indexorderbycols
Definition: pathnodes.h:1182
signed short int16
Definition: c.h:346
char maxParallelHazard
Definition: pathnodes.h:147
List * group_pathkeys
Definition: pathnodes.h:300
struct ProjectionPath ProjectionPath
struct UpperUniquePath UpperUniquePath
List * rowMarks
Definition: pathnodes.h:292
struct QualCost QualCost
Relids ph_needed
Definition: pathnodes.h:2270
List * qual
Definition: pathnodes.h:1636
Definition: fmgr.h:56
Selectivity leftendsel
Definition: pathnodes.h:2042
List * path_mergeclauses
Definition: pathnodes.h:1553
UpperRelationKind
Definition: pathnodes.h:71
int join_cur_level
Definition: pathnodes.h:257
List * outersortkeys
Definition: pathnodes.h:1554
List * distinctList
Definition: pathnodes.h:1734
List * unique_for_rels
Definition: pathnodes.h:700
struct HashPath HashPath
JoinPath jpath
Definition: pathnodes.h:1571
PathTarget * pathtarget
Definition: pathnodes.h:1117
Query * parse
Definition: pathnodes.h:179
List * statlist
Definition: pathnodes.h:681
List * returningLists
Definition: pathnodes.h:1783
struct EquivalenceMember EquivalenceMember
Index security_level
Definition: pathnodes.h:1957
OnConflictExpr * onconflict
Definition: pathnodes.h:1785
struct StatisticExtInfo StatisticExtInfo
List * groupClause
Definition: pathnodes.h:1684
Node * limitOffset
Definition: pathnodes.h:1796
Path path
Definition: pathnodes.h:1178
NodeTag type
Definition: pathnodes.h:2181
Path * subpath
Definition: pathnodes.h:1620
Relids ph_eval_at
Definition: pathnodes.h:2268
List * plan_params
Definition: pathnodes.h:193
PlaceHolderVar * ph_var
Definition: pathnodes.h:2267
IndexOptInfo * indexinfo
Definition: pathnodes.h:1179
SemiAntiJoinFactors semifactors
Definition: pathnodes.h:2388
Index nominalRelation
Definition: pathnodes.h:1776
Oid * indexcollations
Definition: pathnodes.h:805
bool hasJoinRTEs
Definition: pathnodes.h:345
Path * fdw_outerpath
Definition: pathnodes.h:1321
RelOptKind reloptkind
Definition: pathnodes.h:640
Relids * attr_needed
Definition: pathnodes.h:676
bool ec_merging_done
Definition: pathnodes.h:268
PartitionwiseAggregateType
Definition: pathnodes.h:2422
List * custom_paths
Definition: pathnodes.h:1351
List * query_pathkeys
Definition: pathnodes.h:298
int num_batches
Definition: pathnodes.h:1573
List * join_info_list
Definition: pathnodes.h:283
Relids required_relids
Definition: pathnodes.h:1963
SetOpStrategy strategy
Definition: pathnodes.h:1733
Relids min_righthand
Definition: pathnodes.h:2136
AggStrategy aggstrategy
Definition: pathnodes.h:1663
bool materialize_inner
Definition: pathnodes.h:1557
void * join_search_private
Definition: pathnodes.h:361
int num_child_cols
Definition: pathnodes.h:2225
Selectivity right_mcvfreq
Definition: pathnodes.h:2009
Relids curOuterRels
Definition: pathnodes.h:357
List * qual
Definition: pathnodes.h:1667
PlannerInfo * parent_root
Definition: pathnodes.h:185
bool leakproof
Definition: pathnodes.h:1955
double limit_tuples
Definition: pathnodes.h:1379
Index ec_min_security
Definition: pathnodes.h:946
Expr * orclause
Definition: pathnodes.h:1976
Selectivity outer_match_frac
Definition: pathnodes.h:2365
Path * innerjoinpath
Definition: pathnodes.h:1498
List * indextlist
Definition: pathnodes.h:818
AttrNumber * parent_colnos
Definition: pathnodes.h:2226
struct Path * cheapest_startup_path
Definition: pathnodes.h:660
Oid userid
Definition: pathnodes.h:693
QualCost finalCost
Definition: pathnodes.h:63
struct PartitionSchemeData PartitionSchemeData
Relids em_nullable_relids
Definition: pathnodes.h:986
int lastPlanNodeId
Definition: pathnodes.h:137
double tuples
Definition: pathnodes.h:683
Oid reltablespace
Definition: pathnodes.h:672
Path * subpath
Definition: pathnodes.h:1731
struct RollupData RollupData
List * baserestrictinfo
Definition: pathnodes.h:705
NodeTag type
Definition: pathnodes.h:1112
List * ec_derives
Definition: pathnodes.h:938
struct BitmapOrPath BitmapOrPath
AggClauseCosts agg_partial_costs
Definition: pathnodes.h:2447
Relids clause_relids
Definition: pathnodes.h:1960
struct UniquePath UniquePath
Param * param
Definition: pathnodes.h:2289
struct AppendPath AppendPath
int parallel_workers
Definition: pathnodes.h:1123
bool pseudoconstant
Definition: pathnodes.h:1953
bool consider_param_startup
Definition: pathnodes.h:650
RelOptKind
Definition: pathnodes.h:601
List * resultRelations
Definition: pathnodes.h:121
bool is_hashed
Definition: pathnodes.h:1689
ParamPathInfo * param_info
Definition: pathnodes.h:1119
Definition: nodes.h:525
List * part_schemes
Definition: pathnodes.h:305
PartitionwiseAggregateType patype
Definition: pathnodes.h:2454
List * appendRelations
Definition: pathnodes.h:125
Oid * sortopfamily
Definition: pathnodes.h:808
struct MergeAppendPath MergeAppendPath
struct BitmapAndPath BitmapAndPath
List * partial_pathlist
Definition: pathnodes.h:659
Oid reltablespace
Definition: pathnodes.h:792
Relids left_relids
Definition: pathnodes.h:1972
List * join_rel_list
Definition: pathnodes.h:246
struct CustomPath CustomPath
struct AggClauseCosts AggClauseCosts
bool ec_below_outer_join
Definition: pathnodes.h:943
uint32 flags
Definition: pathnodes.h:1349
bool hasNonSerial
Definition: pathnodes.h:61
uint32 BlockNumber
Definition: block.h:31
struct JoinPathExtraData JoinPathExtraData
EquivalenceClass * right_ec
Definition: pathnodes.h:1994
List * cheapest_parameterized_paths
Definition: pathnodes.h:663
List * minmax_aggs
Definition: pathnodes.h:329
bool single_copy
Definition: pathnodes.h:1468
bool hypothetical
Definition: pathnodes.h:829
Index baserestrict_min_security
Definition: pathnodes.h:707
UniquePathMethod umethod
Definition: pathnodes.h:1454
struct GatherPath GatherPath
Path * subpath
Definition: pathnodes.h:1428
List * indexclauses
Definition: pathnodes.h:1180
NodeTag type
Definition: pathnodes.h:638
double Selectivity
Definition: nodes.h:658
Index ec_max_security
Definition: pathnodes.h:947
bool hasNonPartial
Definition: pathnodes.h:60
bool useridiscurrent
Definition: pathnodes.h:694
AggSplit aggsplit
Definition: pathnodes.h:1664
bool immediate
Definition: pathnodes.h:828
QualCost transCost
Definition: pathnodes.h:62
List * partitioned_rels
Definition: pathnodes.h:1401
Selectivity bitmapselectivity
Definition: pathnodes.h:1265
double tuples
Definition: pathnodes.h:797
unsigned int Oid
Definition: postgres_ext.h:31
NodeTag
Definition: nodes.h:26
List * quals
Definition: pathnodes.h:1712
List ** nullable_partexprs
Definition: pathnodes.h:727
struct ForeignKeyOptInfo ForeignKeyOptInfo
AttrNumber * grouping_map
Definition: pathnodes.h:328
List * fkey_list
Definition: pathnodes.h:296
int tree_height
Definition: pathnodes.h:798
double inner_rows_total
Definition: pathnodes.h:1574
bool hasRecursion
Definition: pathnodes.h:350
struct PlaceHolderInfo PlaceHolderInfo
double numGroups
Definition: pathnodes.h:1665
double numGroups
Definition: pathnodes.h:1737
List * mergeopfamilies
Definition: pathnodes.h:1990
List * translated_vars
Definition: pathnodes.h:2217
struct AppendRelInfo AppendRelInfo
SetOpStrategy
Definition: nodes.h:806
Cost inner_rescan_run_cost
Definition: pathnodes.h:2498
struct EquivalenceClass EquivalenceClass
Oid parent_reltype
Definition: pathnodes.h:2198
Relids syn_lefthand
Definition: pathnodes.h:2137
List * rowMarks
Definition: pathnodes.h:1760
int pk_strategy
Definition: pathnodes.h:1015
double numGroups
Definition: pathnodes.h:1687
InheritanceKind
Definition: pathnodes.h:89
Cost startup
Definition: pathnodes.h:45
double allvisfrac
Definition: pathnodes.h:684
Relids outer_relids
Definition: pathnodes.h:1966
signed int int32
Definition: c.h:347
static struct cvec * eclass(struct vars *v, chr c, int cases)
Definition: regc_locale.c:508
List * bitmapquals
Definition: pathnodes.h:1264
Selectivity norm_selec
Definition: pathnodes.h:1983
List * custom_private
Definition: pathnodes.h:1352
JoinType
Definition: nodes.h:692
int first_partial_path
Definition: pathnodes.h:1378
WindowClause * winclause
Definition: pathnodes.h:1722
struct MaterialPath MaterialPath
struct RelOptInfo ** simple_rel_array
Definition: pathnodes.h:203
List * bitmapquals
Definition: pathnodes.h:1277
int num_workers
Definition: pathnodes.h:1469
List * rootResultRelations
Definition: pathnodes.h:123
List * multiexpr_params
Definition: pathnodes.h:263
BlockNumber pages
Definition: pathnodes.h:796
NodeTag pathtype
Definition: pathnodes.h:1114
Relids syn_righthand
Definition: pathnodes.h:2138
List * subpaths
Definition: pathnodes.h:1376
PlannerInfo * subroot
Definition: pathnodes.h:687
NodeTag type
Definition: pathnodes.h:1011
SetOpCmd cmd
Definition: pathnodes.h:1732
struct LockRowsPath LockRowsPath
bool dependsOnRole
Definition: pathnodes.h:141
bool consider_startup
Definition: pathnodes.h:649
Definition: dynahash.c:208
struct ParamPathInfo ParamPathInfo
Relids lateral_relids
Definition: pathnodes.h:668
Cost per_tuple
Definition: pathnodes.h:46
const struct CustomPathMethods * methods
Definition: pathnodes.h:1353
int wt_param_id
Definition: pathnodes.h:353
double tuple_fraction
Definition: pathnodes.h:336
Path * subpath
Definition: pathnodes.h:1721
bool skip_mark_restore
Definition: pathnodes.h:1556
RelOptInfo * rel
Definition: pathnodes.h:793
bool amoptionalkey
Definition: pathnodes.h:833
SpecialJoinInfo * sjinfo
Definition: pathnodes.h:2387
struct GroupingSetData GroupingSetData
List ** partexprs
Definition: pathnodes.h:726
bool parallelModeNeeded
Definition: pathnodes.h:145
Relids all_baserels
Definition: pathnodes.h:227
bool pk_nulls_first
Definition: pathnodes.h:1016
List * paramExecTypes
Definition: pathnodes.h:131
Relids param_source_rels
Definition: pathnodes.h:2389
NodeTag type
Definition: pathnodes.h:1073
double limit_tuples
Definition: pathnodes.h:337
struct PathKey PathKey
EquivalenceMember * left_em
Definition: pathnodes.h:1995
struct AggPath AggPath
Cost indextotalcost
Definition: pathnodes.h:1184
Cost startup_cost
Definition: pathnodes.h:1127
List * semi_rhs_exprs
Definition: pathnodes.h:2146
NodeTag type
Definition: pathnodes.h:1045
bool hasLateralRTEs
Definition: pathnodes.h:346
List * indexcols
Definition: pathnodes.h:1229
Path * subpath
Definition: pathnodes.h:1795
struct ModifyTablePath ModifyTablePath
List * joinrestrictinfo
Definition: pathnodes.h:1500
bool parallelModeOK
Definition: pathnodes.h:143
EquivalenceClass * parent_ec
Definition: pathnodes.h:1979
bool partColsUpdated
Definition: pathnodes.h:1778
struct GatherMergePath GatherMergePath
RTEKind
Definition: parsenodes.h:955
Bitmapset * rewindPlanIDs
Definition: pathnodes.h:115
RelOptInfo * parent
Definition: pathnodes.h:1116
AttrNumber indexcol
Definition: pathnodes.h:1228
List * uniq_exprs
Definition: pathnodes.h:1456
Path * bitmapqual
Definition: pathnodes.h:1252
struct ForeignPath ForeignPath
bool outerjoin_delayed
Definition: pathnodes.h:1949
Path path
Definition: pathnodes.h:1633
List * ec_sources
Definition: pathnodes.h:937
struct Path * cheapest_total_path
Definition: pathnodes.h:661
Selectivity rightstartsel
Definition: pathnodes.h:2043
List * curOuterParams
Definition: pathnodes.h:358
struct RelOptInfo RelOptInfo
struct JoinPath JoinPath
Selectivity indexselectivity
Definition: pathnodes.h:1185
List * subplans
Definition: pathnodes.h:111
bool amcanorderbyop
Definition: pathnodes.h:832
struct RestrictInfo * rinfo
Definition: pathnodes.h:1225
List * joininfo
Definition: pathnodes.h:709
Relids ec_relids
Definition: pathnodes.h:939
PlannerGlobal * glob
Definition: pathnodes.h:181
bool outer_is_left
Definition: pathnodes.h:2000
bool partColsUpdated
Definition: pathnodes.h:364
struct FdwRoutine * fdwroutine
Definition: pathnodes.h:696
List * left_join_clauses
Definition: pathnodes.h:272
int nparts
Definition: pathnodes.h:721
ScanDirection
Definition: sdir.h:22
List * full_join_clauses
Definition: pathnodes.h:280
List * groupClause
Definition: pathnodes.h:1666
Index * sortgrouprefs
Definition: pathnodes.h:1047
List * mergeclause_list
Definition: pathnodes.h:2385
struct Path Path
unsigned int uint32
Definition: c.h:359
AttrNumber flagColIdx
Definition: pathnodes.h:1735
Relids relids
Definition: pathnodes.h:643
AggStrategy aggstrategy
Definition: pathnodes.h:1700
Selectivity outer_selec
Definition: pathnodes.h:1986
Path * subpath
Definition: pathnodes.h:1467
struct GroupingSetsPath GroupingSetsPath
double total_table_pages
Definition: pathnodes.h:333
Selectivity bitmapselectivity
Definition: pathnodes.h:1278
RelOptInfo * rel
Definition: pathnodes.h:885
struct MinMaxAggPath MinMaxAggPath
int simple_rel_array_size
Definition: pathnodes.h:204
bool amhasgetbitmap
Definition: pathnodes.h:837
List * canon_pathkeys
Definition: pathnodes.h:270
struct PartitionSchemeData * PartitionScheme
Definition: pathnodes.h:407
List * non_unique_for_rels
Definition: pathnodes.h:702
List * indexquals
Definition: pathnodes.h:1226
List * ppilist
Definition: pathnodes.h:658
Index relid
Definition: pathnodes.h:671
List * sort_pathkeys
Definition: pathnodes.h:303
struct PlaceHolderVar PlaceHolderVar
RangeTblEntry ** simple_rte_array
Definition: pathnodes.h:211
EquivalenceMember * right_em
Definition: pathnodes.h:1996
Relids lateral_referencers
Definition: pathnodes.h:679
Expr * clause
Definition: pathnodes.h:1945
int numOrderedAggs
Definition: pathnodes.h:59
Path * subpath
Definition: pathnodes.h:1759
struct PlannerGlobal PlannerGlobal
Oid serverid
Definition: pathnodes.h:692
List * ec_opfamilies
Definition: pathnodes.h:934
List * exprs
Definition: pathnodes.h:1046
List * window_pathkeys
Definition: pathnodes.h:301
List * indrestrictinfo
Definition: pathnodes.h:820
Relids direct_lateral_relids
Definition: pathnodes.h:667
Path * outerjoinpath
Definition: pathnodes.h:1497
struct MergeScanSelCache MergeScanSelCache
List * invalItems
Definition: pathnodes.h:129
struct MergePath MergePath
struct GroupResultPath GroupResultPath
bool consider_partitionwise_join
Definition: pathnodes.h:714
NodeTag type
Definition: pathnodes.h:177
JoinPath NestPath
Definition: pathnodes.h:1513
Relids nullable_relids
Definition: pathnodes.h:1969
double inner_rows_total
Definition: pathnodes.h:2509
bool delay_upper_joins
Definition: pathnodes.h:2141
List * indexorderbys
Definition: pathnodes.h:1181
struct RestrictInfo RestrictInfo
struct ProjectSetPath ProjectSetPath
struct IndexClause IndexClause
int rel_parallel_workers
Definition: pathnodes.h:689
List * groupClause
Definition: pathnodes.h:1635
List * append_rel_list
Definition: pathnodes.h:290
struct SemiAntiJoinFactors SemiAntiJoinFactors
struct LimitPath LimitPath
struct AppendRelInfo ** append_rel_array
Definition: pathnodes.h:219
Index lastPHId
Definition: pathnodes.h:133
List * cte_plan_ids
Definition: pathnodes.h:261
List * mmaggregates
Definition: pathnodes.h:1711
Relids ph_lateral
Definition: pathnodes.h:2269
struct PartitionBoundInfoData * boundinfo
Definition: pathnodes.h:722
List * tidquals
Definition: pathnodes.h:1291
Path * subpath
Definition: pathnodes.h:1634
unsigned int Index
Definition: c.h:476
struct GroupPath GroupPath
RTEKind rtekind
Definition: pathnodes.h:673
List * indexlist
Definition: pathnodes.h:680
List * init_plans
Definition: pathnodes.h:259
List * in_operators
Definition: pathnodes.h:1455
double rows
Definition: pathnodes.h:646
bool hasPseudoConstantQuals
Definition: pathnodes.h:348
bool amhasgettuple
Definition: pathnodes.h:836
List * distinct_pathkeys
Definition: pathnodes.h:302
bool is_pushed_down
Definition: pathnodes.h:1947
void * fdw_private
Definition: pathnodes.h:697
Cost total_cost
Definition: pathnodes.h:1128
NodeTag type
Definition: pathnodes.h:789
CostSelector
Definition: pathnodes.h:34
Selectivity left_bucketsize
Definition: pathnodes.h:2006
int firstFlag
Definition: pathnodes.h:1736
double outer_skip_rows
Definition: pathnodes.h:2503
List * pathkeys
Definition: pathnodes.h:1130
Relids right_relids
Definition: pathnodes.h:1973
BlockNumber pages
Definition: pathnodes.h:682
Path path
Definition: pathnodes.h:1490
struct BitmapHeapPath BitmapHeapPath
ParamListInfo boundParams
Definition: pathnodes.h:109
Expr * target
Definition: pathnodes.h:2285
List * eq_classes
Definition: pathnodes.h:266
List ** join_rel_level
Definition: pathnodes.h:256
UniquePathMethod
Definition: pathnodes.h:1443
NodeTag type
Definition: pathnodes.h:107
Path * subpath
Definition: pathnodes.h:1606
double rows
Definition: pathnodes.h:1126
bool parallel_safe
Definition: pathnodes.h:1122
List * lateral_vars
Definition: pathnodes.h:678
struct WindowAggPath WindowAggPath
InheritanceKind inhTargetKind
Definition: pathnodes.h:342
struct PlannerParamItem PlannerParamItem
struct FmgrInfo * partsupfunc
Definition: pathnodes.h:404
Index rootRelation
Definition: pathnodes.h:1777
JoinType jointype
Definition: pathnodes.h:2139
EquivalenceClass * pk_eclass
Definition: pathnodes.h:1013
Bitmapset * outer_params
Definition: pathnodes.h:194
Selectivity left_mcvfreq
Definition: pathnodes.h:2008
List * ppi_clauses
Definition: pathnodes.h:1077
struct RelOptInfo ** part_rels
Definition: pathnodes.h:724
struct Path * non_recursive_path
Definition: pathnodes.h:354
#define INDEX_MAX_KEYS
size_t Size
Definition: c.h:467
Oid hashjoinoperator
Definition: pathnodes.h:2003
NodeTag type
Definition: pathnodes.h:1943
QualCost cost
Definition: pathnodes.h:1048
AggSplit
Definition: nodes.h:776
bool ec_has_volatile
Definition: pathnodes.h:942
List * relationOids
Definition: pathnodes.h:127
List * subroots
Definition: pathnodes.h:113
bool amsearcharray
Definition: pathnodes.h:834
struct HTAB * join_rel_hash
Definition: pathnodes.h:247
bool inner_unique
Definition: pathnodes.h:1494
Index qual_security_level
Definition: pathnodes.h:339
bool consider_parallel
Definition: pathnodes.h:651
int nkeycolumns
Definition: pathnodes.h:802
List * innersortkeys
Definition: pathnodes.h:1555
Path * subpath
Definition: pathnodes.h:1662
Oid * opcintype
Definition: pathnodes.h:807
List * partitioned_rels
Definition: pathnodes.h:1375
Bitmapset * Relids
Definition: pathnodes.h:28
Index query_level
Definition: pathnodes.h:183
Oid pk_opfamily
Definition: pathnodes.h:1014
double ppi_rows
Definition: pathnodes.h:1076
Path path
Definition: pathnodes.h:1794
Path path
Definition: pathnodes.h:1290
Oid * opfamily
Definition: pathnodes.h:806
List * withCheckOptionLists
Definition: pathnodes.h:1782
List * finalrtable
Definition: pathnodes.h:117
List * partitioned_child_rels
Definition: pathnodes.h:728
AggStrategy
Definition: nodes.h:754
Bitmapset * keys
Definition: pathnodes.h:887
Index phlevelsup
Definition: pathnodes.h:2067
Index lastRowMarkId
Definition: pathnodes.h:135
AttrNumber max_attr
Definition: pathnodes.h:675
Selectivity match_count
Definition: pathnodes.h:2366
Selectivity right_bucketsize
Definition: pathnodes.h:2007
EquivalenceClass * left_ec
Definition: pathnodes.h:1993
struct JoinCostWorkspace JoinCostWorkspace
Relids nullable_baserels
Definition: pathnodes.h:235
struct RecursiveUnionPath RecursiveUnionPath
List * fdw_private
Definition: pathnodes.h:1322
SetOpCmd
Definition: nodes.h:798
JoinType jointype
Definition: pathnodes.h:1492
List * semi_operators
Definition: pathnodes.h:2145
ScanDirection indexscandir
Definition: pathnodes.h:1183
CmdType operation
Definition: pathnodes.h:1774
struct MinMaxAggInfo MinMaxAggInfo
struct SubqueryScanPath SubqueryScanPath
List * placeholder_list
Definition: pathnodes.h:294
List * resultRelations
Definition: pathnodes.h:1779
Size transitionSpace
Definition: pathnodes.h:64
double numGroups
Definition: pathnodes.h:1678
bool hashable
Definition: pathnodes.h:1688
bool hasHavingQual
Definition: pathnodes.h:347
JoinPath jpath
Definition: pathnodes.h:1552
PartitionScheme part_scheme
Definition: pathnodes.h:720
bool parallel_aware
Definition: pathnodes.h:1121
int * indexkeys
Definition: pathnodes.h:803
List * path_hashclauses
Definition: pathnodes.h:1572
struct PathTarget PathTarget
List * initial_rels
Definition: pathnodes.h:308
List * pathlist
Definition: pathnodes.h:657
Relids ppi_req_outer
Definition: pathnodes.h:1075
MemoryContext planner_cxt
Definition: pathnodes.h:331
List * right_join_clauses
Definition: pathnodes.h:276
Index child_relid
Definition: pathnodes.h:2190
bool * canreturn
Definition: pathnodes.h:811
struct IndexPath IndexPath
bool amsearchnulls
Definition: pathnodes.h:835
List * partition_qual
Definition: pathnodes.h:723
bool * nulls_first
Definition: pathnodes.h:810
struct SetOpPath SetOpPath
Path * subpath
Definition: pathnodes.h:1594
NodeTag type
Definition: pathnodes.h:1224
Index parent_relid
Definition: pathnodes.h:2189
bool * reverse_sort
Definition: pathnodes.h:809
PartitionDirectory partition_directory
Definition: pathnodes.h:149
double inner_skip_rows
Definition: pathnodes.h:2504
List * processed_tlist
Definition: pathnodes.h:325
List * indpred
Definition: pathnodes.h:816
int32 * attr_widths
Definition: pathnodes.h:677
AggClauseCosts agg_final_costs
Definition: pathnodes.h:2448
Node * limitCount
Definition: pathnodes.h:1797
List * finalrowmarks
Definition: pathnodes.h:119
struct SortPath SortPath
Definition: pg_list.h:50
Path path
Definition: pathnodes.h:1619
struct PathTarget * reltarget
Definition: pathnodes.h:654
Relids min_lefthand
Definition: pathnodes.h:2135
int16 AttrNumber
Definition: attnum.h:21
QualCost baserestrictcost
Definition: pathnodes.h:706
List * subplan_params
Definition: pathnodes.h:688
Path path
Definition: pathnodes.h:1730
NodeTag type
Definition: pathnodes.h:2281
CmdType
Definition: nodes.h:668
List * gsets_data
Definition: pathnodes.h:1686
Bitmapset * eclass_indexes
Definition: pathnodes.h:685
Path path
Definition: pathnodes.h:1661
double limit_tuples
Definition: pathnodes.h:1403
struct EquivalenceClass * ec_merged
Definition: pathnodes.h:948
Selectivity rightendsel
Definition: pathnodes.h:2044
bool amcanparallel
Definition: pathnodes.h:838
double Cost
Definition: nodes.h:659
List * scansel_cache
Definition: pathnodes.h:1997
Selectivity leftstartsel
Definition: pathnodes.h:2041
List * ec_members
Definition: pathnodes.h:936
List * indexprs
Definition: pathnodes.h:815
Relids top_parent_relids
Definition: pathnodes.h:716
bool transientPlan
Definition: pathnodes.h:139
List * gsets
Definition: pathnodes.h:1685
bool is_dummy_rel(RelOptInfo *rel)
Definition: joinrels.c:1208
Path * subpath
Definition: pathnodes.h:1453
PlannerInfo * subroot
Definition: pathnodes.h:2286
AttrNumber min_attr
Definition: pathnodes.h:674