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nodes.h
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1 /*-------------------------------------------------------------------------
2  *
3  * nodes.h
4  * Definitions for tagged nodes.
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/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  */
41 
42  /*
43  * TAGS FOR PLAN NODES (plannodes.h)
44  */
88  /* these aren't subclasses of Plan: */
96 
97  /*
98  * TAGS FOR PLAN STATE NODES (execnodes.h)
99  *
100  * These should correspond one-to-one with Plan node types.
101  */
145 
146  /*
147  * TAGS FOR PRIMITIVE NODES (primnodes.h)
148  */
201 
202  /*
203  * TAGS FOR EXPRESSION STATE NODES (execnodes.h)
204  *
205  * ExprState represents the evaluation state for a whole expression tree.
206  * Most Expr-based plan nodes do not have a corresponding expression state
207  * node, they're fully handled within execExpr* - but sometimes the state
208  * needs to be shared with other parts of the executor, as for example
209  * with AggrefExprState, which nodeAgg.c has to modify.
210  */
217 
218  /*
219  * TAGS FOR PLANNER NODES (pathnodes.h)
220  */
261  /* these aren't subclasses of Path: */
277 
278  /*
279  * TAGS FOR MEMORY NODES (memnodes.h)
280  */
285 
286  /*
287  * TAGS FOR VALUE NODES (value.h)
288  */
295 
296  /*
297  * TAGS FOR LIST NODES (pg_list.h)
298  */
302 
303  /*
304  * TAGS FOR EXTENSIBLE NODES (extensible.h)
305  */
307 
308  /*
309  * TAGS FOR STATEMENT NODES (mostly in parsenodes.h)
310  */
427 
428  /*
429  * TAGS FOR PARSE TREE NODES (parsenodes.h)
430  */
483 
484  /*
485  * TAGS FOR REPLICATION GRAMMAR PARSE NODES (replnodes.h)
486  */
494 
495  /*
496  * TAGS FOR RANDOM OTHER STUFF
497  *
498  * These are objects that aren't part of parse/plan/execute node tree
499  * structures, but we give them NodeTags anyway for identification
500  * purposes (usually because they are involved in APIs where we want to
501  * pass multiple object types through the same pointer).
502  */
503  T_TriggerData, /* in commands/trigger.h */
504  T_EventTriggerData, /* in commands/event_trigger.h */
505  T_ReturnSetInfo, /* in nodes/execnodes.h */
506  T_WindowObjectData, /* private in nodeWindowAgg.c */
507  T_TIDBitmap, /* in nodes/tidbitmap.h */
508  T_InlineCodeBlock, /* in nodes/parsenodes.h */
509  T_FdwRoutine, /* in foreign/fdwapi.h */
510  T_IndexAmRoutine, /* in access/amapi.h */
511  T_TableAmRoutine, /* in access/tableam.h */
512  T_TsmRoutine, /* in access/tsmapi.h */
513  T_ForeignKeyCacheInfo, /* in utils/rel.h */
514  T_CallContext, /* in nodes/parsenodes.h */
515  T_SupportRequestSimplify, /* in nodes/supportnodes.h */
516  T_SupportRequestSelectivity, /* in nodes/supportnodes.h */
517  T_SupportRequestCost, /* in nodes/supportnodes.h */
518  T_SupportRequestRows, /* in nodes/supportnodes.h */
519  T_SupportRequestIndexCondition /* in nodes/supportnodes.h */
520 } NodeTag;
521 
522 /*
523  * The first field of a node of any type is guaranteed to be the NodeTag.
524  * Hence the type of any node can be gotten by casting it to Node. Declaring
525  * a variable to be of Node * (instead of void *) can also facilitate
526  * debugging.
527  */
528 typedef struct Node
529 {
531 } Node;
532 
533 #define nodeTag(nodeptr) (((const Node*)(nodeptr))->type)
534 
535 /*
536  * newNode -
537  * create a new node of the specified size and tag the node with the
538  * specified tag.
539  *
540  * !WARNING!: Avoid using newNode directly. You should be using the
541  * macro makeNode. eg. to create a Query node, use makeNode(Query)
542  *
543  * Note: the size argument should always be a compile-time constant, so the
544  * apparent risk of multiple evaluation doesn't matter in practice.
545  */
546 #ifdef __GNUC__
547 
548 /* With GCC, we can use a compound statement within an expression */
549 #define newNode(size, tag) \
550 ({ Node *_result; \
551  AssertMacro((size) >= sizeof(Node)); /* need the tag, at least */ \
552  _result = (Node *) palloc0fast(size); \
553  _result->type = (tag); \
554  _result; \
555 })
556 #else
557 
558 /*
559  * There is no way to dereference the palloc'ed pointer to assign the
560  * tag, and also return the pointer itself, so we need a holder variable.
561  * Fortunately, this macro isn't recursive so we just define
562  * a global variable for this purpose.
563  */
565 
566 #define newNode(size, tag) \
567 ( \
568  AssertMacro((size) >= sizeof(Node)), /* need the tag, at least */ \
569  newNodeMacroHolder = (Node *) palloc0fast(size), \
570  newNodeMacroHolder->type = (tag), \
571  newNodeMacroHolder \
572 )
573 #endif /* __GNUC__ */
574 
575 
576 #define makeNode(_type_) ((_type_ *) newNode(sizeof(_type_),T_##_type_))
577 #define NodeSetTag(nodeptr,t) (((Node*)(nodeptr))->type = (t))
578 
579 #define IsA(nodeptr,_type_) (nodeTag(nodeptr) == T_##_type_)
580 
581 /*
582  * castNode(type, ptr) casts ptr to "type *", and if assertions are enabled,
583  * verifies that the node has the appropriate type (using its nodeTag()).
584  *
585  * Use an inline function when assertions are enabled, to avoid multiple
586  * evaluations of the ptr argument (which could e.g. be a function call).
587  */
588 #ifdef USE_ASSERT_CHECKING
589 static inline Node *
590 castNodeImpl(NodeTag type, void *ptr)
591 {
592  Assert(ptr == NULL || nodeTag(ptr) == type);
593  return (Node *) ptr;
594 }
595 #define castNode(_type_, nodeptr) ((_type_ *) castNodeImpl(T_##_type_, nodeptr))
596 #else
597 #define castNode(_type_, nodeptr) ((_type_ *) (nodeptr))
598 #endif /* USE_ASSERT_CHECKING */
599 
600 
601 /* ----------------------------------------------------------------
602  * extern declarations follow
603  * ----------------------------------------------------------------
604  */
605 
606 /*
607  * nodes/{outfuncs.c,print.c}
608  */
609 struct Bitmapset; /* not to include bitmapset.h here */
610 struct StringInfoData; /* not to include stringinfo.h here */
611 
612 extern void outNode(struct StringInfoData *str, const void *obj);
613 extern void outToken(struct StringInfoData *str, const char *s);
614 extern void outBitmapset(struct StringInfoData *str,
615  const struct Bitmapset *bms);
616 extern void outDatum(struct StringInfoData *str, uintptr_t value,
617  int typlen, bool typbyval);
618 extern char *nodeToString(const void *obj);
619 extern char *bmsToString(const struct Bitmapset *bms);
620 
621 /*
622  * nodes/{readfuncs.c,read.c}
623  */
624 extern void *stringToNode(const char *str);
625 #ifdef WRITE_READ_PARSE_PLAN_TREES
626 extern void *stringToNodeWithLocations(const char *str);
627 #endif
628 extern struct Bitmapset *readBitmapset(void);
629 extern uintptr_t readDatum(bool typbyval);
630 extern bool *readBoolCols(int numCols);
631 extern int *readIntCols(int numCols);
632 extern Oid *readOidCols(int numCols);
633 extern int16 *readAttrNumberCols(int numCols);
634 
635 /*
636  * nodes/copyfuncs.c
637  */
638 extern void *copyObjectImpl(const void *obj);
639 
640 /* cast result back to argument type, if supported by compiler */
641 #ifdef HAVE_TYPEOF
642 #define copyObject(obj) ((typeof(obj)) copyObjectImpl(obj))
643 #else
644 #define copyObject(obj) copyObjectImpl(obj)
645 #endif
646 
647 /*
648  * nodes/equalfuncs.c
649  */
650 extern bool equal(const void *a, const void *b);
651 
652 
653 /*
654  * Typedefs for identifying qualifier selectivities and plan costs as such.
655  * These are just plain "double"s, but declaring a variable as Selectivity
656  * or Cost makes the intent more obvious.
657  *
658  * These could have gone into plannodes.h or some such, but many files
659  * depend on them...
660  */
661 typedef double Selectivity; /* fraction of tuples a qualifier will pass */
662 typedef double Cost; /* execution cost (in page-access units) */
663 
664 
665 /*
666  * CmdType -
667  * enums for type of operation represented by a Query or PlannedStmt
668  *
669  * This is needed in both parsenodes.h and plannodes.h, so put it here...
670  */
671 typedef enum CmdType
672 {
674  CMD_SELECT, /* select stmt */
675  CMD_UPDATE, /* update stmt */
676  CMD_INSERT, /* insert stmt */
678  CMD_UTILITY, /* cmds like create, destroy, copy, vacuum,
679  * etc. */
680  CMD_NOTHING /* dummy command for instead nothing rules
681  * with qual */
682 } CmdType;
683 
684 
685 /*
686  * JoinType -
687  * enums for types of relation joins
688  *
689  * JoinType determines the exact semantics of joining two relations using
690  * a matching qualification. For example, it tells what to do with a tuple
691  * that has no match in the other relation.
692  *
693  * This is needed in both parsenodes.h and plannodes.h, so put it here...
694  */
695 typedef enum JoinType
696 {
697  /*
698  * The canonical kinds of joins according to the SQL JOIN syntax. Only
699  * these codes can appear in parser output (e.g., JoinExpr nodes).
700  */
701  JOIN_INNER, /* matching tuple pairs only */
702  JOIN_LEFT, /* pairs + unmatched LHS tuples */
703  JOIN_FULL, /* pairs + unmatched LHS + unmatched RHS */
704  JOIN_RIGHT, /* pairs + unmatched RHS tuples */
705 
706  /*
707  * Semijoins and anti-semijoins (as defined in relational theory) do not
708  * appear in the SQL JOIN syntax, but there are standard idioms for
709  * representing them (e.g., using EXISTS). The planner recognizes these
710  * cases and converts them to joins. So the planner and executor must
711  * support these codes. NOTE: in JOIN_SEMI output, it is unspecified
712  * which matching RHS row is joined to. In JOIN_ANTI output, the row is
713  * guaranteed to be null-extended.
714  */
715  JOIN_SEMI, /* 1 copy of each LHS row that has match(es) */
716  JOIN_ANTI, /* 1 copy of each LHS row that has no match */
717 
718  /*
719  * These codes are used internally in the planner, but are not supported
720  * by the executor (nor, indeed, by most of the planner).
721  */
722  JOIN_UNIQUE_OUTER, /* LHS path must be made unique */
723  JOIN_UNIQUE_INNER /* RHS path must be made unique */
724 
725  /*
726  * We might need additional join types someday.
727  */
728 } JoinType;
729 
730 /*
731  * OUTER joins are those for which pushed-down quals must behave differently
732  * from the join's own quals. This is in fact everything except INNER and
733  * SEMI joins. However, this macro must also exclude the JOIN_UNIQUE symbols
734  * since those are temporary proxies for what will eventually be an INNER
735  * join.
736  *
737  * Note: semijoins are a hybrid case, but we choose to treat them as not
738  * being outer joins. This is okay principally because the SQL syntax makes
739  * it impossible to have a pushed-down qual that refers to the inner relation
740  * of a semijoin; so there is no strong need to distinguish join quals from
741  * pushed-down quals. This is convenient because for almost all purposes,
742  * quals attached to a semijoin can be treated the same as innerjoin quals.
743  */
744 #define IS_OUTER_JOIN(jointype) \
745  (((1 << (jointype)) & \
746  ((1 << JOIN_LEFT) | \
747  (1 << JOIN_FULL) | \
748  (1 << JOIN_RIGHT) | \
749  (1 << JOIN_ANTI))) != 0)
750 
751 /*
752  * AggStrategy -
753  * overall execution strategies for Agg plan nodes
754  *
755  * This is needed in both pathnodes.h and plannodes.h, so put it here...
756  */
757 typedef enum AggStrategy
758 {
759  AGG_PLAIN, /* simple agg across all input rows */
760  AGG_SORTED, /* grouped agg, input must be sorted */
761  AGG_HASHED, /* grouped agg, use internal hashtable */
762  AGG_MIXED /* grouped agg, hash and sort both used */
763 } AggStrategy;
764 
765 /*
766  * AggSplit -
767  * splitting (partial aggregation) modes for Agg plan nodes
768  *
769  * This is needed in both pathnodes.h and plannodes.h, so put it here...
770  */
771 
772 /* Primitive options supported by nodeAgg.c: */
773 #define AGGSPLITOP_COMBINE 0x01 /* substitute combinefn for transfn */
774 #define AGGSPLITOP_SKIPFINAL 0x02 /* skip finalfn, return state as-is */
775 #define AGGSPLITOP_SERIALIZE 0x04 /* apply serialfn to output */
776 #define AGGSPLITOP_DESERIALIZE 0x08 /* apply deserialfn to input */
777 
778 /* Supported operating modes (i.e., useful combinations of these options): */
779 typedef enum AggSplit
780 {
781  /* Basic, non-split aggregation: */
783  /* Initial phase of partial aggregation, with serialization: */
785  /* Final phase of partial aggregation, with deserialization: */
787 } AggSplit;
788 
789 /* Test whether an AggSplit value selects each primitive option: */
790 #define DO_AGGSPLIT_COMBINE(as) (((as) & AGGSPLITOP_COMBINE) != 0)
791 #define DO_AGGSPLIT_SKIPFINAL(as) (((as) & AGGSPLITOP_SKIPFINAL) != 0)
792 #define DO_AGGSPLIT_SERIALIZE(as) (((as) & AGGSPLITOP_SERIALIZE) != 0)
793 #define DO_AGGSPLIT_DESERIALIZE(as) (((as) & AGGSPLITOP_DESERIALIZE) != 0)
794 
795 /*
796  * SetOpCmd and SetOpStrategy -
797  * overall semantics and execution strategies for SetOp plan nodes
798  *
799  * This is needed in both pathnodes.h and plannodes.h, so put it here...
800  */
801 typedef enum SetOpCmd
802 {
807 } SetOpCmd;
808 
809 typedef enum SetOpStrategy
810 {
811  SETOP_SORTED, /* input must be sorted */
812  SETOP_HASHED /* use internal hashtable */
813 } SetOpStrategy;
814 
815 /*
816  * OnConflictAction -
817  * "ON CONFLICT" clause type of query
818  *
819  * This is needed in both parsenodes.h and plannodes.h, so put it here...
820  */
821 typedef enum OnConflictAction
822 {
823  ONCONFLICT_NONE, /* No "ON CONFLICT" clause */
824  ONCONFLICT_NOTHING, /* ON CONFLICT ... DO NOTHING */
825  ONCONFLICT_UPDATE /* ON CONFLICT ... DO UPDATE */
827 
828 /*
829  * LimitOption -
830  * LIMIT option of query
831  *
832  * This is needed in both parsenodes.h and plannodes.h, so put it here...
833  */
834 typedef enum LimitOption
835 {
836  LIMIT_OPTION_COUNT, /* FETCH FIRST... ONLY */
837  LIMIT_OPTION_WITH_TIES, /* FETCH FIRST... WITH TIES */
838  LIMIT_OPTION_DEFAULT, /* No limit present */
839 } LimitOption;
840 
841 #endif /* NODES_H */
uintptr_t readDatum(bool typbyval)
Definition: readfuncs.c:2901
signed short int16
Definition: c.h:361
Definition: nodes.h:79
void * stringToNode(const char *str)
Definition: read.c:89
Oid * readOidCols(int numCols)
Definition: readfuncs.c:2982
Definition: nodes.h:81
static struct @142 value
Definition: nodes.h:54
char * bmsToString(const struct Bitmapset *bms)
Definition: nodes.h:528
int16 * readAttrNumberCols(int numCols)
Definition: readfuncs.c:2958
Definition: nodes.h:49
Definition: nodes.h:76
double Selectivity
Definition: nodes.h:661
unsigned int Oid
Definition: postgres_ext.h:31
NodeTag
Definition: nodes.h:26
void outToken(struct StringInfoData *str, const char *s)
SetOpStrategy
Definition: nodes.h:809
#define PGDLLIMPORT
Definition: c.h:1257
JoinType
Definition: nodes.h:695
char * nodeToString(const void *obj)
Definition: outfuncs.c:4361
#define AGGSPLITOP_DESERIALIZE
Definition: nodes.h:776
Definition: nodes.h:46
Definition: nodes.h:152
#define AGGSPLITOP_COMBINE
Definition: nodes.h:773
Definition: nodes.h:78
struct Bitmapset * readBitmapset(void)
Definition: readfuncs.c:238
NodeTag type
Definition: nodes.h:530
Definition: nodes.h:149
Definition: nodes.h:299
Definition: nodes.h:154
Definition: nodes.h:153
Definition: nodes.h:312
struct Node Node
Definition: nodes.h:84
bool * readBoolCols(int numCols)
Definition: readfuncs.c:3030
#define AGGSPLITOP_SERIALIZE
Definition: nodes.h:775
#define Assert(condition)
Definition: c.h:745
void outDatum(struct StringInfoData *str, uintptr_t value, int typlen, bool typbyval)
int * readIntCols(int numCols)
Definition: readfuncs.c:3006
AggSplit
Definition: nodes.h:779
Definition: nodes.h:289
#define AGGSPLITOP_SKIPFINAL
Definition: nodes.h:774
void outBitmapset(struct StringInfoData *str, const struct Bitmapset *bms)
LimitOption
Definition: nodes.h:834
#define nodeTag(nodeptr)
Definition: nodes.h:533
Definition: nodes.h:45
Definition: nodes.h:71
PGDLLIMPORT Node * newNodeMacroHolder
Definition: nodes.c:31
Definition: nodes.h:294
Definition: nodes.h:85
void * copyObjectImpl(const void *obj)
Definition: copyfuncs.c:4822
Definition: nodes.h:291
AggStrategy
Definition: nodes.h:757
SetOpCmd
Definition: nodes.h:801
Definition: nodes.h:82
bool equal(const void *a, const void *b)
Definition: equalfuncs.c:3032
Definition: nodes.h:227
OnConflictAction
Definition: nodes.h:821
CmdType
Definition: nodes.h:671
double Cost
Definition: nodes.h:662
Definition: nodes.h:39
void outNode(struct StringInfoData *str, const void *obj)
Definition: nodes.h:155
Definition: nodes.h:87