1 /*-------------------------------------------------------------------------
2  *
3  * nodes.h
4  *	  Definitions for tagged nodes.
5  *
6  *
7  * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/include/nodes/nodes.h
11  *
12  *-------------------------------------------------------------------------
13  */
14 #ifndef NODES_H
15 #define NODES_H
16 
17 /*
18  * The first field of every node is NodeTag. Each node created (with makeNode)
19  * will have one of the following tags as the value of its first field.
20  *
21  * Note that inserting or deleting node types changes the numbers of other
22  * node types later in the list.  This is no problem during development, since
23  * the node numbers are never stored on disk.  But don't do it in a released
24  * branch, because that would represent an ABI break for extensions.
25  */
26 typedef enum NodeTag
27 {
28 	T_Invalid = 0,
29 
30 	/*
31 	 * TAGS FOR EXECUTOR NODES (execnodes.h)
32 	 */
33 	T_IndexInfo,
34 	T_ExprContext,
35 	T_ProjectionInfo,
36 	T_JunkFilter,
37 	T_OnConflictSetState,
38 	T_ResultRelInfo,
39 	T_EState,
40 	T_TupleTableSlot,
41 
42 	/*
43 	 * TAGS FOR PLAN NODES (plannodes.h)
44 	 */
45 	T_Plan,
46 	T_Result,
47 	T_ProjectSet,
48 	T_ModifyTable,
49 	T_Append,
50 	T_MergeAppend,
51 	T_RecursiveUnion,
52 	T_BitmapAnd,
53 	T_BitmapOr,
54 	T_Scan,
55 	T_SeqScan,
56 	T_SampleScan,
57 	T_IndexScan,
58 	T_IndexOnlyScan,
59 	T_BitmapIndexScan,
60 	T_BitmapHeapScan,
61 	T_TidScan,
62 	T_SubqueryScan,
63 	T_FunctionScan,
64 	T_ValuesScan,
65 	T_TableFuncScan,
66 	T_CteScan,
67 	T_NamedTuplestoreScan,
68 	T_WorkTableScan,
69 	T_ForeignScan,
70 	T_CustomScan,
71 	T_Join,
72 	T_NestLoop,
73 	T_MergeJoin,
74 	T_HashJoin,
75 	T_Material,
76 	T_Sort,
77 	T_Group,
78 	T_Agg,
79 	T_WindowAgg,
80 	T_Unique,
81 	T_Gather,
82 	T_GatherMerge,
83 	T_Hash,
84 	T_SetOp,
85 	T_LockRows,
86 	T_Limit,
87 	/* these aren't subclasses of Plan: */
88 	T_NestLoopParam,
89 	T_PlanRowMark,
90 	T_PartitionPruneInfo,
91 	T_PartitionedRelPruneInfo,
92 	T_PartitionPruneStepOp,
93 	T_PartitionPruneStepCombine,
94 	T_PlanInvalItem,
95 
96 	/*
97 	 * TAGS FOR PLAN STATE NODES (execnodes.h)
98 	 *
99 	 * These should correspond one-to-one with Plan node types.
100 	 */
101 	T_PlanState,
102 	T_ResultState,
103 	T_ProjectSetState,
104 	T_ModifyTableState,
105 	T_AppendState,
106 	T_MergeAppendState,
107 	T_RecursiveUnionState,
108 	T_BitmapAndState,
109 	T_BitmapOrState,
110 	T_ScanState,
111 	T_SeqScanState,
112 	T_SampleScanState,
113 	T_IndexScanState,
114 	T_IndexOnlyScanState,
115 	T_BitmapIndexScanState,
116 	T_BitmapHeapScanState,
117 	T_TidScanState,
118 	T_SubqueryScanState,
119 	T_FunctionScanState,
120 	T_TableFuncScanState,
121 	T_ValuesScanState,
122 	T_CteScanState,
123 	T_NamedTuplestoreScanState,
124 	T_WorkTableScanState,
125 	T_ForeignScanState,
126 	T_CustomScanState,
127 	T_JoinState,
128 	T_NestLoopState,
129 	T_MergeJoinState,
130 	T_HashJoinState,
131 	T_MaterialState,
132 	T_SortState,
133 	T_GroupState,
134 	T_AggState,
135 	T_WindowAggState,
136 	T_UniqueState,
137 	T_GatherState,
138 	T_GatherMergeState,
139 	T_HashState,
140 	T_SetOpState,
141 	T_LockRowsState,
142 	T_LimitState,
143 
144 	/*
145 	 * TAGS FOR PRIMITIVE NODES (primnodes.h)
146 	 */
147 	T_Alias,
148 	T_RangeVar,
149 	T_TableFunc,
150 	T_Expr,
151 	T_Var,
152 	T_Const,
153 	T_Param,
154 	T_Aggref,
155 	T_GroupingFunc,
156 	T_WindowFunc,
157 	T_ArrayRef,
158 	T_FuncExpr,
159 	T_NamedArgExpr,
160 	T_OpExpr,
161 	T_DistinctExpr,
162 	T_NullIfExpr,
163 	T_ScalarArrayOpExpr,
164 	T_BoolExpr,
165 	T_SubLink,
166 	T_SubPlan,
167 	T_AlternativeSubPlan,
168 	T_FieldSelect,
169 	T_FieldStore,
170 	T_RelabelType,
171 	T_CoerceViaIO,
172 	T_ArrayCoerceExpr,
173 	T_ConvertRowtypeExpr,
174 	T_CollateExpr,
175 	T_CaseExpr,
176 	T_CaseWhen,
177 	T_CaseTestExpr,
178 	T_ArrayExpr,
179 	T_RowExpr,
180 	T_RowCompareExpr,
181 	T_CoalesceExpr,
182 	T_MinMaxExpr,
183 	T_SQLValueFunction,
184 	T_XmlExpr,
185 	T_NullTest,
186 	T_BooleanTest,
187 	T_CoerceToDomain,
188 	T_CoerceToDomainValue,
189 	T_SetToDefault,
190 	T_CurrentOfExpr,
191 	T_NextValueExpr,
192 	T_InferenceElem,
193 	T_TargetEntry,
194 	T_RangeTblRef,
195 	T_JoinExpr,
196 	T_FromExpr,
197 	T_OnConflictExpr,
198 	T_IntoClause,
199 
200 	/*
201 	 * TAGS FOR EXPRESSION STATE NODES (execnodes.h)
202 	 *
203 	 * ExprState represents the evaluation state for a whole expression tree.
204 	 * Most Expr-based plan nodes do not have a corresponding expression state
205 	 * node, they're fully handled within execExpr* - but sometimes the state
206 	 * needs to be shared with other parts of the executor, as for example
207 	 * with AggrefExprState, which nodeAgg.c has to modify.
208 	 */
209 	T_ExprState,
210 	T_AggrefExprState,
211 	T_WindowFuncExprState,
212 	T_SetExprState,
213 	T_SubPlanState,
214 	T_AlternativeSubPlanState,
215 	T_DomainConstraintState,
216 
217 	/*
218 	 * TAGS FOR PLANNER NODES (relation.h)
219 	 */
220 	T_PlannerInfo,
221 	T_PlannerGlobal,
222 	T_RelOptInfo,
223 	T_IndexOptInfo,
224 	T_ForeignKeyOptInfo,
225 	T_ParamPathInfo,
226 	T_Path,
227 	T_IndexPath,
228 	T_BitmapHeapPath,
229 	T_BitmapAndPath,
230 	T_BitmapOrPath,
231 	T_TidPath,
232 	T_SubqueryScanPath,
233 	T_ForeignPath,
234 	T_CustomPath,
235 	T_NestPath,
236 	T_MergePath,
237 	T_HashPath,
238 	T_AppendPath,
239 	T_MergeAppendPath,
240 	T_ResultPath,
241 	T_MaterialPath,
242 	T_UniquePath,
243 	T_GatherPath,
244 	T_GatherMergePath,
245 	T_ProjectionPath,
246 	T_ProjectSetPath,
247 	T_SortPath,
248 	T_GroupPath,
249 	T_UpperUniquePath,
250 	T_AggPath,
251 	T_GroupingSetsPath,
252 	T_MinMaxAggPath,
253 	T_WindowAggPath,
254 	T_SetOpPath,
255 	T_RecursiveUnionPath,
256 	T_LockRowsPath,
257 	T_ModifyTablePath,
258 	T_LimitPath,
259 	/* these aren't subclasses of Path: */
260 	T_EquivalenceClass,
261 	T_EquivalenceMember,
262 	T_PathKey,
263 	T_PathTarget,
264 	T_RestrictInfo,
265 	T_PlaceHolderVar,
266 	T_SpecialJoinInfo,
267 	T_AppendRelInfo,
268 	T_PlaceHolderInfo,
269 	T_MinMaxAggInfo,
270 	T_PlannerParamItem,
271 	T_RollupData,
272 	T_GroupingSetData,
273 	T_StatisticExtInfo,
274 
275 	/*
276 	 * TAGS FOR MEMORY NODES (memnodes.h)
277 	 */
278 	T_MemoryContext,
279 	T_AllocSetContext,
280 	T_SlabContext,
281 	T_GenerationContext,
282 
283 	/*
284 	 * TAGS FOR VALUE NODES (value.h)
285 	 */
286 	T_Value,
287 	T_Integer,
288 	T_Float,
289 	T_String,
290 	T_BitString,
291 	T_Null,
292 
293 	/*
294 	 * TAGS FOR LIST NODES (pg_list.h)
295 	 */
296 	T_List,
297 	T_IntList,
298 	T_OidList,
299 
300 	/*
301 	 * TAGS FOR EXTENSIBLE NODES (extensible.h)
302 	 */
303 	T_ExtensibleNode,
304 
305 	/*
306 	 * TAGS FOR STATEMENT NODES (mostly in parsenodes.h)
307 	 */
308 	T_RawStmt,
309 	T_Query,
310 	T_PlannedStmt,
311 	T_InsertStmt,
312 	T_DeleteStmt,
313 	T_UpdateStmt,
314 	T_SelectStmt,
315 	T_AlterTableStmt,
316 	T_AlterTableCmd,
317 	T_AlterDomainStmt,
318 	T_SetOperationStmt,
319 	T_GrantStmt,
320 	T_GrantRoleStmt,
321 	T_AlterDefaultPrivilegesStmt,
322 	T_ClosePortalStmt,
323 	T_ClusterStmt,
324 	T_CopyStmt,
325 	T_CreateStmt,
326 	T_DefineStmt,
327 	T_DropStmt,
328 	T_TruncateStmt,
329 	T_CommentStmt,
330 	T_FetchStmt,
331 	T_IndexStmt,
332 	T_CreateFunctionStmt,
333 	T_AlterFunctionStmt,
334 	T_DoStmt,
335 	T_RenameStmt,
336 	T_RuleStmt,
337 	T_NotifyStmt,
338 	T_ListenStmt,
339 	T_UnlistenStmt,
340 	T_TransactionStmt,
341 	T_ViewStmt,
342 	T_LoadStmt,
343 	T_CreateDomainStmt,
344 	T_CreatedbStmt,
345 	T_DropdbStmt,
346 	T_VacuumStmt,
347 	T_ExplainStmt,
348 	T_CreateTableAsStmt,
349 	T_CreateSeqStmt,
350 	T_AlterSeqStmt,
351 	T_VariableSetStmt,
352 	T_VariableShowStmt,
353 	T_DiscardStmt,
354 	T_CreateTrigStmt,
355 	T_CreatePLangStmt,
356 	T_CreateRoleStmt,
357 	T_AlterRoleStmt,
358 	T_DropRoleStmt,
359 	T_LockStmt,
360 	T_ConstraintsSetStmt,
361 	T_ReindexStmt,
362 	T_CheckPointStmt,
363 	T_CreateSchemaStmt,
364 	T_AlterDatabaseStmt,
365 	T_AlterDatabaseSetStmt,
366 	T_AlterRoleSetStmt,
367 	T_CreateConversionStmt,
368 	T_CreateCastStmt,
369 	T_CreateOpClassStmt,
370 	T_CreateOpFamilyStmt,
371 	T_AlterOpFamilyStmt,
372 	T_PrepareStmt,
373 	T_ExecuteStmt,
374 	T_DeallocateStmt,
375 	T_DeclareCursorStmt,
376 	T_CreateTableSpaceStmt,
377 	T_DropTableSpaceStmt,
378 	T_AlterObjectDependsStmt,
379 	T_AlterObjectSchemaStmt,
380 	T_AlterOwnerStmt,
381 	T_AlterOperatorStmt,
382 	T_DropOwnedStmt,
383 	T_ReassignOwnedStmt,
384 	T_CompositeTypeStmt,
385 	T_CreateEnumStmt,
386 	T_CreateRangeStmt,
387 	T_AlterEnumStmt,
388 	T_AlterTSDictionaryStmt,
389 	T_AlterTSConfigurationStmt,
390 	T_CreateFdwStmt,
391 	T_AlterFdwStmt,
392 	T_CreateForeignServerStmt,
393 	T_AlterForeignServerStmt,
394 	T_CreateUserMappingStmt,
395 	T_AlterUserMappingStmt,
396 	T_DropUserMappingStmt,
397 	T_AlterTableSpaceOptionsStmt,
398 	T_AlterTableMoveAllStmt,
399 	T_SecLabelStmt,
400 	T_CreateForeignTableStmt,
401 	T_ImportForeignSchemaStmt,
402 	T_CreateExtensionStmt,
403 	T_AlterExtensionStmt,
404 	T_AlterExtensionContentsStmt,
405 	T_CreateEventTrigStmt,
406 	T_AlterEventTrigStmt,
407 	T_RefreshMatViewStmt,
408 	T_ReplicaIdentityStmt,
409 	T_AlterSystemStmt,
410 	T_CreatePolicyStmt,
411 	T_AlterPolicyStmt,
412 	T_CreateTransformStmt,
413 	T_CreateAmStmt,
414 	T_CreatePublicationStmt,
415 	T_AlterPublicationStmt,
416 	T_CreateSubscriptionStmt,
417 	T_AlterSubscriptionStmt,
418 	T_DropSubscriptionStmt,
419 	T_CreateStatsStmt,
420 	T_AlterCollationStmt,
421 	T_CallStmt,
422 
423 	/*
424 	 * TAGS FOR PARSE TREE NODES (parsenodes.h)
425 	 */
426 	T_A_Expr,
427 	T_ColumnRef,
428 	T_ParamRef,
429 	T_A_Const,
430 	T_FuncCall,
431 	T_A_Star,
432 	T_A_Indices,
433 	T_A_Indirection,
434 	T_A_ArrayExpr,
435 	T_ResTarget,
436 	T_MultiAssignRef,
437 	T_TypeCast,
438 	T_CollateClause,
439 	T_SortBy,
440 	T_WindowDef,
441 	T_RangeSubselect,
442 	T_RangeFunction,
443 	T_RangeTableSample,
444 	T_RangeTableFunc,
445 	T_RangeTableFuncCol,
446 	T_TypeName,
447 	T_ColumnDef,
448 	T_IndexElem,
449 	T_Constraint,
450 	T_DefElem,
451 	T_RangeTblEntry,
452 	T_RangeTblFunction,
453 	T_TableSampleClause,
454 	T_WithCheckOption,
455 	T_SortGroupClause,
456 	T_GroupingSet,
457 	T_WindowClause,
458 	T_ObjectWithArgs,
459 	T_AccessPriv,
460 	T_CreateOpClassItem,
461 	T_TableLikeClause,
462 	T_FunctionParameter,
463 	T_LockingClause,
464 	T_RowMarkClause,
465 	T_XmlSerialize,
466 	T_WithClause,
467 	T_InferClause,
468 	T_OnConflictClause,
469 	T_CommonTableExpr,
470 	T_RoleSpec,
471 	T_TriggerTransition,
472 	T_PartitionElem,
473 	T_PartitionSpec,
474 	T_PartitionBoundSpec,
475 	T_PartitionRangeDatum,
476 	T_PartitionCmd,
477 	T_VacuumRelation,
478 
479 	/*
480 	 * TAGS FOR REPLICATION GRAMMAR PARSE NODES (replnodes.h)
481 	 */
482 	T_IdentifySystemCmd,
483 	T_BaseBackupCmd,
484 	T_CreateReplicationSlotCmd,
485 	T_DropReplicationSlotCmd,
486 	T_StartReplicationCmd,
487 	T_TimeLineHistoryCmd,
488 	T_SQLCmd,
489 
490 	/*
491 	 * TAGS FOR RANDOM OTHER STUFF
492 	 *
493 	 * These are objects that aren't part of parse/plan/execute node tree
494 	 * structures, but we give them NodeTags anyway for identification
495 	 * purposes (usually because they are involved in APIs where we want to
496 	 * pass multiple object types through the same pointer).
497 	 */
498 	T_TriggerData,				/* in commands/trigger.h */
499 	T_EventTriggerData,			/* in commands/event_trigger.h */
500 	T_ReturnSetInfo,			/* in nodes/execnodes.h */
501 	T_WindowObjectData,			/* private in nodeWindowAgg.c */
502 	T_TIDBitmap,				/* in nodes/tidbitmap.h */
503 	T_InlineCodeBlock,			/* in nodes/parsenodes.h */
504 	T_FdwRoutine,				/* in foreign/fdwapi.h */
505 	T_IndexAmRoutine,			/* in access/amapi.h */
506 	T_TsmRoutine,				/* in access/tsmapi.h */
507 	T_ForeignKeyCacheInfo,		/* in utils/rel.h */
508 	T_CallContext				/* in nodes/parsenodes.h */
509 } NodeTag;
510 
511 /*
512  * The first field of a node of any type is guaranteed to be the NodeTag.
513  * Hence the type of any node can be gotten by casting it to Node. Declaring
514  * a variable to be of Node * (instead of void *) can also facilitate
515  * debugging.
516  */
517 typedef struct Node
518 {
519 	NodeTag		type;
520 } Node;
521 
522 #define nodeTag(nodeptr)		(((const Node*)(nodeptr))->type)
523 
524 /*
525  * newNode -
526  *	  create a new node of the specified size and tag the node with the
527  *	  specified tag.
528  *
529  * !WARNING!: Avoid using newNode directly. You should be using the
530  *	  macro makeNode.  eg. to create a Query node, use makeNode(Query)
531  *
532  * Note: the size argument should always be a compile-time constant, so the
533  * apparent risk of multiple evaluation doesn't matter in practice.
534  */
535 #ifdef __GNUC__
536 
537 /* With GCC, we can use a compound statement within an expression */
538 #define newNode(size, tag) \
539 ({	Node   *_result; \
540 	AssertMacro((size) >= sizeof(Node));		/* need the tag, at least */ \
541 	_result = (Node *) palloc0fast(size); \
542 	_result->type = (tag); \
543 	_result; \
544 })
545 #else
546 
547 /*
548  *	There is no way to dereference the palloc'ed pointer to assign the
549  *	tag, and also return the pointer itself, so we need a holder variable.
550  *	Fortunately, this macro isn't recursive so we just define
551  *	a global variable for this purpose.
552  */
553 extern PGDLLIMPORT Node *newNodeMacroHolder;
554 
555 #define newNode(size, tag) \
556 ( \
557 	AssertMacro((size) >= sizeof(Node)),		/* need the tag, at least */ \
558 	newNodeMacroHolder = (Node *) palloc0fast(size), \
559 	newNodeMacroHolder->type = (tag), \
560 	newNodeMacroHolder \
561 )
562 #endif							/* __GNUC__ */
563 
564 
565 #define makeNode(_type_)		((_type_ *) newNode(sizeof(_type_),T_##_type_))
566 #define NodeSetTag(nodeptr,t)	(((Node*)(nodeptr))->type = (t))
567 
568 #define IsA(nodeptr,_type_)		(nodeTag(nodeptr) == T_##_type_)
569 
570 /*
571  * castNode(type, ptr) casts ptr to "type *", and if assertions are enabled,
572  * verifies that the node has the appropriate type (using its nodeTag()).
573  *
574  * Use an inline function when assertions are enabled, to avoid multiple
575  * evaluations of the ptr argument (which could e.g. be a function call).
576  */
577 #ifdef USE_ASSERT_CHECKING
578 static inline Node *
castNodeImpl(NodeTag type,void * ptr)579 castNodeImpl(NodeTag type, void *ptr)
580 {
581 	Assert(ptr == NULL || nodeTag(ptr) == type);
582 	return (Node *) ptr;
583 }
584 #define castNode(_type_, nodeptr) ((_type_ *) castNodeImpl(T_##_type_, nodeptr))
585 #else
586 #define castNode(_type_, nodeptr) ((_type_ *) (nodeptr))
587 #endif							/* USE_ASSERT_CHECKING */
588 
589 
590 /* ----------------------------------------------------------------
591  *					  extern declarations follow
592  * ----------------------------------------------------------------
593  */
594 
595 /*
596  * nodes/{outfuncs.c,print.c}
597  */
598 struct Bitmapset;				/* not to include bitmapset.h here */
599 struct StringInfoData;			/* not to include stringinfo.h here */
600 
601 extern void outNode(struct StringInfoData *str, const void *obj);
602 extern void outToken(struct StringInfoData *str, const char *s);
603 extern void outBitmapset(struct StringInfoData *str,
604 			 const struct Bitmapset *bms);
605 extern void outDatum(struct StringInfoData *str, uintptr_t value,
606 		 int typlen, bool typbyval);
607 extern char *nodeToString(const void *obj);
608 extern char *bmsToString(const struct Bitmapset *bms);
609 
610 /*
611  * nodes/{readfuncs.c,read.c}
612  */
613 extern void *stringToNode(char *str);
614 extern struct Bitmapset *readBitmapset(void);
615 extern uintptr_t readDatum(bool typbyval);
616 extern bool *readBoolCols(int numCols);
617 extern int *readIntCols(int numCols);
618 extern Oid *readOidCols(int numCols);
619 extern int16 *readAttrNumberCols(int numCols);
620 
621 /*
622  * nodes/copyfuncs.c
623  */
624 extern void *copyObjectImpl(const void *obj);
625 
626 /* cast result back to argument type, if supported by compiler */
627 #ifdef HAVE_TYPEOF
628 #define copyObject(obj) ((typeof(obj)) copyObjectImpl(obj))
629 #else
630 #define copyObject(obj) copyObjectImpl(obj)
631 #endif
632 
633 /*
634  * nodes/equalfuncs.c
635  */
636 extern bool equal(const void *a, const void *b);
637 
638 
639 /*
640  * Typedefs for identifying qualifier selectivities and plan costs as such.
641  * These are just plain "double"s, but declaring a variable as Selectivity
642  * or Cost makes the intent more obvious.
643  *
644  * These could have gone into plannodes.h or some such, but many files
645  * depend on them...
646  */
647 typedef double Selectivity;		/* fraction of tuples a qualifier will pass */
648 typedef double Cost;			/* execution cost (in page-access units) */
649 
650 
651 /*
652  * CmdType -
653  *	  enums for type of operation represented by a Query or PlannedStmt
654  *
655  * This is needed in both parsenodes.h and plannodes.h, so put it here...
656  */
657 typedef enum CmdType
658 {
659 	CMD_UNKNOWN,
660 	CMD_SELECT,					/* select stmt */
661 	CMD_UPDATE,					/* update stmt */
662 	CMD_INSERT,					/* insert stmt */
663 	CMD_DELETE,
664 	CMD_UTILITY,				/* cmds like create, destroy, copy, vacuum,
665 								 * etc. */
666 	CMD_NOTHING					/* dummy command for instead nothing rules
667 								 * with qual */
668 } CmdType;
669 
670 
671 /*
672  * JoinType -
673  *	  enums for types of relation joins
674  *
675  * JoinType determines the exact semantics of joining two relations using
676  * a matching qualification.  For example, it tells what to do with a tuple
677  * that has no match in the other relation.
678  *
679  * This is needed in both parsenodes.h and plannodes.h, so put it here...
680  */
681 typedef enum JoinType
682 {
683 	/*
684 	 * The canonical kinds of joins according to the SQL JOIN syntax. Only
685 	 * these codes can appear in parser output (e.g., JoinExpr nodes).
686 	 */
687 	JOIN_INNER,					/* matching tuple pairs only */
688 	JOIN_LEFT,					/* pairs + unmatched LHS tuples */
689 	JOIN_FULL,					/* pairs + unmatched LHS + unmatched RHS */
690 	JOIN_RIGHT,					/* pairs + unmatched RHS tuples */
691 
692 	/*
693 	 * Semijoins and anti-semijoins (as defined in relational theory) do not
694 	 * appear in the SQL JOIN syntax, but there are standard idioms for
695 	 * representing them (e.g., using EXISTS).  The planner recognizes these
696 	 * cases and converts them to joins.  So the planner and executor must
697 	 * support these codes.  NOTE: in JOIN_SEMI output, it is unspecified
698 	 * which matching RHS row is joined to.  In JOIN_ANTI output, the row is
699 	 * guaranteed to be null-extended.
700 	 */
701 	JOIN_SEMI,					/* 1 copy of each LHS row that has match(es) */
702 	JOIN_ANTI,					/* 1 copy of each LHS row that has no match */
703 
704 	/*
705 	 * These codes are used internally in the planner, but are not supported
706 	 * by the executor (nor, indeed, by most of the planner).
707 	 */
708 	JOIN_UNIQUE_OUTER,			/* LHS path must be made unique */
709 	JOIN_UNIQUE_INNER			/* RHS path must be made unique */
710 
711 	/*
712 	 * We might need additional join types someday.
713 	 */
714 } JoinType;
715 
716 /*
717  * OUTER joins are those for which pushed-down quals must behave differently
718  * from the join's own quals.  This is in fact everything except INNER and
719  * SEMI joins.  However, this macro must also exclude the JOIN_UNIQUE symbols
720  * since those are temporary proxies for what will eventually be an INNER
721  * join.
722  *
723  * Note: semijoins are a hybrid case, but we choose to treat them as not
724  * being outer joins.  This is okay principally because the SQL syntax makes
725  * it impossible to have a pushed-down qual that refers to the inner relation
726  * of a semijoin; so there is no strong need to distinguish join quals from
727  * pushed-down quals.  This is convenient because for almost all purposes,
728  * quals attached to a semijoin can be treated the same as innerjoin quals.
729  */
730 #define IS_OUTER_JOIN(jointype) \
731 	(((1 << (jointype)) & \
732 	  ((1 << JOIN_LEFT) | \
733 	   (1 << JOIN_FULL) | \
734 	   (1 << JOIN_RIGHT) | \
735 	   (1 << JOIN_ANTI))) != 0)
736 
737 /*
738  * AggStrategy -
739  *	  overall execution strategies for Agg plan nodes
740  *
741  * This is needed in both plannodes.h and relation.h, so put it here...
742  */
743 typedef enum AggStrategy
744 {
745 	AGG_PLAIN,					/* simple agg across all input rows */
746 	AGG_SORTED,					/* grouped agg, input must be sorted */
747 	AGG_HASHED,					/* grouped agg, use internal hashtable */
748 	AGG_MIXED					/* grouped agg, hash and sort both used */
749 } AggStrategy;
750 
751 /*
752  * AggSplit -
753  *	  splitting (partial aggregation) modes for Agg plan nodes
754  *
755  * This is needed in both plannodes.h and relation.h, so put it here...
756  */
757 
758 /* Primitive options supported by nodeAgg.c: */
759 #define AGGSPLITOP_COMBINE		0x01	/* substitute combinefn for transfn */
760 #define AGGSPLITOP_SKIPFINAL	0x02	/* skip finalfn, return state as-is */
761 #define AGGSPLITOP_SERIALIZE	0x04	/* apply serializefn to output */
762 #define AGGSPLITOP_DESERIALIZE	0x08	/* apply deserializefn to input */
763 
764 /* Supported operating modes (i.e., useful combinations of these options): */
765 typedef enum AggSplit
766 {
767 	/* Basic, non-split aggregation: */
768 	AGGSPLIT_SIMPLE = 0,
769 	/* Initial phase of partial aggregation, with serialization: */
770 	AGGSPLIT_INITIAL_SERIAL = AGGSPLITOP_SKIPFINAL | AGGSPLITOP_SERIALIZE,
771 	/* Final phase of partial aggregation, with deserialization: */
772 	AGGSPLIT_FINAL_DESERIAL = AGGSPLITOP_COMBINE | AGGSPLITOP_DESERIALIZE
773 } AggSplit;
774 
775 /* Test whether an AggSplit value selects each primitive option: */
776 #define DO_AGGSPLIT_COMBINE(as)		(((as) & AGGSPLITOP_COMBINE) != 0)
777 #define DO_AGGSPLIT_SKIPFINAL(as)	(((as) & AGGSPLITOP_SKIPFINAL) != 0)
778 #define DO_AGGSPLIT_SERIALIZE(as)	(((as) & AGGSPLITOP_SERIALIZE) != 0)
779 #define DO_AGGSPLIT_DESERIALIZE(as) (((as) & AGGSPLITOP_DESERIALIZE) != 0)
780 
781 /*
782  * SetOpCmd and SetOpStrategy -
783  *	  overall semantics and execution strategies for SetOp plan nodes
784  *
785  * This is needed in both plannodes.h and relation.h, so put it here...
786  */
787 typedef enum SetOpCmd
788 {
789 	SETOPCMD_INTERSECT,
790 	SETOPCMD_INTERSECT_ALL,
791 	SETOPCMD_EXCEPT,
792 	SETOPCMD_EXCEPT_ALL
793 } SetOpCmd;
794 
795 typedef enum SetOpStrategy
796 {
797 	SETOP_SORTED,				/* input must be sorted */
798 	SETOP_HASHED				/* use internal hashtable */
799 } SetOpStrategy;
800 
801 /*
802  * OnConflictAction -
803  *	  "ON CONFLICT" clause type of query
804  *
805  * This is needed in both parsenodes.h and plannodes.h, so put it here...
806  */
807 typedef enum OnConflictAction
808 {
809 	ONCONFLICT_NONE,			/* No "ON CONFLICT" clause */
810 	ONCONFLICT_NOTHING,			/* ON CONFLICT ... DO NOTHING */
811 	ONCONFLICT_UPDATE			/* ON CONFLICT ... DO UPDATE */
812 } OnConflictAction;
813 
814 #endif							/* NODES_H */
815