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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) 1996-2019, 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  */
87  /* these aren't subclasses of Plan: */
95 
96  /*
97  * TAGS FOR PLAN STATE NODES (execnodes.h)
98  *
99  * These should correspond one-to-one with Plan node types.
100  */
143 
144  /*
145  * TAGS FOR PRIMITIVE NODES (primnodes.h)
146  */
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  */
216 
217  /*
218  * TAGS FOR PLANNER NODES (pathnodes.h)
219  */
259  /* these aren't subclasses of Path: */
275 
276  /*
277  * TAGS FOR MEMORY NODES (memnodes.h)
278  */
283 
284  /*
285  * TAGS FOR VALUE NODES (value.h)
286  */
293 
294  /*
295  * TAGS FOR LIST NODES (pg_list.h)
296  */
300 
301  /*
302  * TAGS FOR EXTENSIBLE NODES (extensible.h)
303  */
305 
306  /*
307  * TAGS FOR STATEMENT NODES (mostly in parsenodes.h)
308  */
424 
425  /*
426  * TAGS FOR PARSE TREE NODES (parsenodes.h)
427  */
480 
481  /*
482  * TAGS FOR REPLICATION GRAMMAR PARSE NODES (replnodes.h)
483  */
491 
492  /*
493  * TAGS FOR RANDOM OTHER STUFF
494  *
495  * These are objects that aren't part of parse/plan/execute node tree
496  * structures, but we give them NodeTags anyway for identification
497  * purposes (usually because they are involved in APIs where we want to
498  * pass multiple object types through the same pointer).
499  */
500  T_TriggerData, /* in commands/trigger.h */
501  T_EventTriggerData, /* in commands/event_trigger.h */
502  T_ReturnSetInfo, /* in nodes/execnodes.h */
503  T_WindowObjectData, /* private in nodeWindowAgg.c */
504  T_TIDBitmap, /* in nodes/tidbitmap.h */
505  T_InlineCodeBlock, /* in nodes/parsenodes.h */
506  T_FdwRoutine, /* in foreign/fdwapi.h */
507  T_IndexAmRoutine, /* in access/amapi.h */
508  T_TableAmRoutine, /* in access/tableam.h */
509  T_TsmRoutine, /* in access/tsmapi.h */
510  T_ForeignKeyCacheInfo, /* in utils/rel.h */
511  T_CallContext, /* in nodes/parsenodes.h */
512  T_SupportRequestSimplify, /* in nodes/supportnodes.h */
513  T_SupportRequestSelectivity, /* in nodes/supportnodes.h */
514  T_SupportRequestCost, /* in nodes/supportnodes.h */
515  T_SupportRequestRows, /* in nodes/supportnodes.h */
516  T_SupportRequestIndexCondition /* in nodes/supportnodes.h */
517 } NodeTag;
518 
519 /*
520  * The first field of a node of any type is guaranteed to be the NodeTag.
521  * Hence the type of any node can be gotten by casting it to Node. Declaring
522  * a variable to be of Node * (instead of void *) can also facilitate
523  * debugging.
524  */
525 typedef struct Node
526 {
528 } Node;
529 
530 #define nodeTag(nodeptr) (((const Node*)(nodeptr))->type)
531 
532 /*
533  * newNode -
534  * create a new node of the specified size and tag the node with the
535  * specified tag.
536  *
537  * !WARNING!: Avoid using newNode directly. You should be using the
538  * macro makeNode. eg. to create a Query node, use makeNode(Query)
539  *
540  * Note: the size argument should always be a compile-time constant, so the
541  * apparent risk of multiple evaluation doesn't matter in practice.
542  */
543 #ifdef __GNUC__
544 
545 /* With GCC, we can use a compound statement within an expression */
546 #define newNode(size, tag) \
547 ({ Node *_result; \
548  AssertMacro((size) >= sizeof(Node)); /* need the tag, at least */ \
549  _result = (Node *) palloc0fast(size); \
550  _result->type = (tag); \
551  _result; \
552 })
553 #else
554 
555 /*
556  * There is no way to dereference the palloc'ed pointer to assign the
557  * tag, and also return the pointer itself, so we need a holder variable.
558  * Fortunately, this macro isn't recursive so we just define
559  * a global variable for this purpose.
560  */
562 
563 #define newNode(size, tag) \
564 ( \
565  AssertMacro((size) >= sizeof(Node)), /* need the tag, at least */ \
566  newNodeMacroHolder = (Node *) palloc0fast(size), \
567  newNodeMacroHolder->type = (tag), \
568  newNodeMacroHolder \
569 )
570 #endif /* __GNUC__ */
571 
572 
573 #define makeNode(_type_) ((_type_ *) newNode(sizeof(_type_),T_##_type_))
574 #define NodeSetTag(nodeptr,t) (((Node*)(nodeptr))->type = (t))
575 
576 #define IsA(nodeptr,_type_) (nodeTag(nodeptr) == T_##_type_)
577 
578 /*
579  * castNode(type, ptr) casts ptr to "type *", and if assertions are enabled,
580  * verifies that the node has the appropriate type (using its nodeTag()).
581  *
582  * Use an inline function when assertions are enabled, to avoid multiple
583  * evaluations of the ptr argument (which could e.g. be a function call).
584  */
585 #ifdef USE_ASSERT_CHECKING
586 static inline Node *
587 castNodeImpl(NodeTag type, void *ptr)
588 {
589  Assert(ptr == NULL || nodeTag(ptr) == type);
590  return (Node *) ptr;
591 }
592 #define castNode(_type_, nodeptr) ((_type_ *) castNodeImpl(T_##_type_, nodeptr))
593 #else
594 #define castNode(_type_, nodeptr) ((_type_ *) (nodeptr))
595 #endif /* USE_ASSERT_CHECKING */
596 
597 
598 /* ----------------------------------------------------------------
599  * extern declarations follow
600  * ----------------------------------------------------------------
601  */
602 
603 /*
604  * nodes/{outfuncs.c,print.c}
605  */
606 struct Bitmapset; /* not to include bitmapset.h here */
607 struct StringInfoData; /* not to include stringinfo.h here */
608 
609 extern void outNode(struct StringInfoData *str, const void *obj);
610 extern void outToken(struct StringInfoData *str, const char *s);
611 extern void outBitmapset(struct StringInfoData *str,
612  const struct Bitmapset *bms);
613 extern void outDatum(struct StringInfoData *str, uintptr_t value,
614  int typlen, bool typbyval);
615 extern char *nodeToString(const void *obj);
616 extern char *bmsToString(const struct Bitmapset *bms);
617 
618 /*
619  * nodes/{readfuncs.c,read.c}
620  */
621 extern void *stringToNode(const char *str);
622 #ifdef WRITE_READ_PARSE_PLAN_TREES
623 extern void *stringToNodeWithLocations(const char *str);
624 #endif
625 extern struct Bitmapset *readBitmapset(void);
626 extern uintptr_t readDatum(bool typbyval);
627 extern bool *readBoolCols(int numCols);
628 extern int *readIntCols(int numCols);
629 extern Oid *readOidCols(int numCols);
630 extern int16 *readAttrNumberCols(int numCols);
631 
632 /*
633  * nodes/copyfuncs.c
634  */
635 extern void *copyObjectImpl(const void *obj);
636 
637 /* cast result back to argument type, if supported by compiler */
638 #ifdef HAVE_TYPEOF
639 #define copyObject(obj) ((typeof(obj)) copyObjectImpl(obj))
640 #else
641 #define copyObject(obj) copyObjectImpl(obj)
642 #endif
643 
644 /*
645  * nodes/equalfuncs.c
646  */
647 extern bool equal(const void *a, const void *b);
648 
649 
650 /*
651  * Typedefs for identifying qualifier selectivities and plan costs as such.
652  * These are just plain "double"s, but declaring a variable as Selectivity
653  * or Cost makes the intent more obvious.
654  *
655  * These could have gone into plannodes.h or some such, but many files
656  * depend on them...
657  */
658 typedef double Selectivity; /* fraction of tuples a qualifier will pass */
659 typedef double Cost; /* execution cost (in page-access units) */
660 
661 
662 /*
663  * CmdType -
664  * enums for type of operation represented by a Query or PlannedStmt
665  *
666  * This is needed in both parsenodes.h and plannodes.h, so put it here...
667  */
668 typedef enum CmdType
669 {
671  CMD_SELECT, /* select stmt */
672  CMD_UPDATE, /* update stmt */
673  CMD_INSERT, /* insert stmt */
675  CMD_UTILITY, /* cmds like create, destroy, copy, vacuum,
676  * etc. */
677  CMD_NOTHING /* dummy command for instead nothing rules
678  * with qual */
679 } CmdType;
680 
681 
682 /*
683  * JoinType -
684  * enums for types of relation joins
685  *
686  * JoinType determines the exact semantics of joining two relations using
687  * a matching qualification. For example, it tells what to do with a tuple
688  * that has no match in the other relation.
689  *
690  * This is needed in both parsenodes.h and plannodes.h, so put it here...
691  */
692 typedef enum JoinType
693 {
694  /*
695  * The canonical kinds of joins according to the SQL JOIN syntax. Only
696  * these codes can appear in parser output (e.g., JoinExpr nodes).
697  */
698  JOIN_INNER, /* matching tuple pairs only */
699  JOIN_LEFT, /* pairs + unmatched LHS tuples */
700  JOIN_FULL, /* pairs + unmatched LHS + unmatched RHS */
701  JOIN_RIGHT, /* pairs + unmatched RHS tuples */
702 
703  /*
704  * Semijoins and anti-semijoins (as defined in relational theory) do not
705  * appear in the SQL JOIN syntax, but there are standard idioms for
706  * representing them (e.g., using EXISTS). The planner recognizes these
707  * cases and converts them to joins. So the planner and executor must
708  * support these codes. NOTE: in JOIN_SEMI output, it is unspecified
709  * which matching RHS row is joined to. In JOIN_ANTI output, the row is
710  * guaranteed to be null-extended.
711  */
712  JOIN_SEMI, /* 1 copy of each LHS row that has match(es) */
713  JOIN_ANTI, /* 1 copy of each LHS row that has no match */
714 
715  /*
716  * These codes are used internally in the planner, but are not supported
717  * by the executor (nor, indeed, by most of the planner).
718  */
719  JOIN_UNIQUE_OUTER, /* LHS path must be made unique */
720  JOIN_UNIQUE_INNER /* RHS path must be made unique */
721 
722  /*
723  * We might need additional join types someday.
724  */
725 } JoinType;
726 
727 /*
728  * OUTER joins are those for which pushed-down quals must behave differently
729  * from the join's own quals. This is in fact everything except INNER and
730  * SEMI joins. However, this macro must also exclude the JOIN_UNIQUE symbols
731  * since those are temporary proxies for what will eventually be an INNER
732  * join.
733  *
734  * Note: semijoins are a hybrid case, but we choose to treat them as not
735  * being outer joins. This is okay principally because the SQL syntax makes
736  * it impossible to have a pushed-down qual that refers to the inner relation
737  * of a semijoin; so there is no strong need to distinguish join quals from
738  * pushed-down quals. This is convenient because for almost all purposes,
739  * quals attached to a semijoin can be treated the same as innerjoin quals.
740  */
741 #define IS_OUTER_JOIN(jointype) \
742  (((1 << (jointype)) & \
743  ((1 << JOIN_LEFT) | \
744  (1 << JOIN_FULL) | \
745  (1 << JOIN_RIGHT) | \
746  (1 << JOIN_ANTI))) != 0)
747 
748 /*
749  * AggStrategy -
750  * overall execution strategies for Agg plan nodes
751  *
752  * This is needed in both pathnodes.h and plannodes.h, so put it here...
753  */
754 typedef enum AggStrategy
755 {
756  AGG_PLAIN, /* simple agg across all input rows */
757  AGG_SORTED, /* grouped agg, input must be sorted */
758  AGG_HASHED, /* grouped agg, use internal hashtable */
759  AGG_MIXED /* grouped agg, hash and sort both used */
760 } AggStrategy;
761 
762 /*
763  * AggSplit -
764  * splitting (partial aggregation) modes for Agg plan nodes
765  *
766  * This is needed in both pathnodes.h and plannodes.h, so put it here...
767  */
768 
769 /* Primitive options supported by nodeAgg.c: */
770 #define AGGSPLITOP_COMBINE 0x01 /* substitute combinefn for transfn */
771 #define AGGSPLITOP_SKIPFINAL 0x02 /* skip finalfn, return state as-is */
772 #define AGGSPLITOP_SERIALIZE 0x04 /* apply serialfn to output */
773 #define AGGSPLITOP_DESERIALIZE 0x08 /* apply deserialfn to input */
774 
775 /* Supported operating modes (i.e., useful combinations of these options): */
776 typedef enum AggSplit
777 {
778  /* Basic, non-split aggregation: */
780  /* Initial phase of partial aggregation, with serialization: */
782  /* Final phase of partial aggregation, with deserialization: */
784 } AggSplit;
785 
786 /* Test whether an AggSplit value selects each primitive option: */
787 #define DO_AGGSPLIT_COMBINE(as) (((as) & AGGSPLITOP_COMBINE) != 0)
788 #define DO_AGGSPLIT_SKIPFINAL(as) (((as) & AGGSPLITOP_SKIPFINAL) != 0)
789 #define DO_AGGSPLIT_SERIALIZE(as) (((as) & AGGSPLITOP_SERIALIZE) != 0)
790 #define DO_AGGSPLIT_DESERIALIZE(as) (((as) & AGGSPLITOP_DESERIALIZE) != 0)
791 
792 /*
793  * SetOpCmd and SetOpStrategy -
794  * overall semantics and execution strategies for SetOp plan nodes
795  *
796  * This is needed in both pathnodes.h and plannodes.h, so put it here...
797  */
798 typedef enum SetOpCmd
799 {
804 } SetOpCmd;
805 
806 typedef enum SetOpStrategy
807 {
808  SETOP_SORTED, /* input must be sorted */
809  SETOP_HASHED /* use internal hashtable */
810 } SetOpStrategy;
811 
812 /*
813  * OnConflictAction -
814  * "ON CONFLICT" clause type of query
815  *
816  * This is needed in both parsenodes.h and plannodes.h, so put it here...
817  */
818 typedef enum OnConflictAction
819 {
820  ONCONFLICT_NONE, /* No "ON CONFLICT" clause */
821  ONCONFLICT_NOTHING, /* ON CONFLICT ... DO NOTHING */
822  ONCONFLICT_UPDATE /* ON CONFLICT ... DO UPDATE */
824 
825 #endif /* NODES_H */
uintptr_t readDatum(bool typbyval)
Definition: readfuncs.c:2830
signed short int16
Definition: c.h:345
Definition: nodes.h:78
void * stringToNode(const char *str)
Definition: read.c:89
Oid * readOidCols(int numCols)
Definition: readfuncs.c:2911
Definition: nodes.h:80
Definition: nodes.h:54
char * bmsToString(const struct Bitmapset *bms)
static struct @145 value
Definition: nodes.h:525
int16 * readAttrNumberCols(int numCols)
Definition: readfuncs.c:2887
Definition: nodes.h:49
Definition: nodes.h:76
double Selectivity
Definition: nodes.h:658
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:806
#define PGDLLIMPORT
Definition: c.h:1243
JoinType
Definition: nodes.h:692
char * nodeToString(const void *obj)
Definition: outfuncs.c:4316
#define AGGSPLITOP_DESERIALIZE
Definition: nodes.h:773
Definition: nodes.h:46
Definition: nodes.h:150
#define AGGSPLITOP_COMBINE
Definition: nodes.h:770
Definition: nodes.h:77
struct Bitmapset * readBitmapset(void)
Definition: readfuncs.c:238
NodeTag type
Definition: nodes.h:527
Definition: nodes.h:147
Definition: nodes.h:297
Definition: nodes.h:152
Definition: nodes.h:151
Definition: nodes.h:310
struct Node Node
Definition: nodes.h:83
bool * readBoolCols(int numCols)
Definition: readfuncs.c:2959
#define AGGSPLITOP_SERIALIZE
Definition: nodes.h:772
#define Assert(condition)
Definition: c.h:732
void outDatum(struct StringInfoData *str, uintptr_t value, int typlen, bool typbyval)
int * readIntCols(int numCols)
Definition: readfuncs.c:2935
AggSplit
Definition: nodes.h:776
Definition: nodes.h:287
#define AGGSPLITOP_SKIPFINAL
Definition: nodes.h:771
void outBitmapset(struct StringInfoData *str, const struct Bitmapset *bms)
#define nodeTag(nodeptr)
Definition: nodes.h:530
Definition: nodes.h:45
Definition: nodes.h:71
PGDLLIMPORT Node * newNodeMacroHolder
Definition: nodes.c:31
Definition: nodes.h:292
Definition: nodes.h:84
void * copyObjectImpl(const void *obj)
Definition: copyfuncs.c:4757
Definition: nodes.h:289
AggStrategy
Definition: nodes.h:754
SetOpCmd
Definition: nodes.h:798
Definition: nodes.h:81
bool equal(const void *a, const void *b)
Definition: equalfuncs.c:3008
Definition: nodes.h:226
OnConflictAction
Definition: nodes.h:818
CmdType
Definition: nodes.h:668
double Cost
Definition: nodes.h:659
Definition: nodes.h:39
void outNode(struct StringInfoData *str, const void *obj)
Definition: nodes.h:153
Definition: nodes.h:86