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pg_trigger.h
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1 /*-------------------------------------------------------------------------
2  *
3  * pg_trigger.h
4  * definition of the "trigger" system catalog (pg_trigger)
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/catalog/pg_trigger.h
11  *
12  * NOTES
13  * The Catalog.pm module reads this file and derives schema
14  * information.
15  *
16  *-------------------------------------------------------------------------
17  */
18 #ifndef PG_TRIGGER_H
19 #define PG_TRIGGER_H
20 
21 #include "catalog/genbki.h"
22 #include "catalog/pg_trigger_d.h"
23 
24 /* ----------------
25  * pg_trigger definition. cpp turns this into
26  * typedef struct FormData_pg_trigger
27  *
28  * Note: when tgconstraint is nonzero, tgconstrrelid, tgconstrindid,
29  * tgdeferrable, and tginitdeferred are largely redundant with the referenced
30  * pg_constraint entry. However, it is possible for a non-deferrable trigger
31  * to be associated with a deferrable constraint.
32  * ----------------
33  */
34 CATALOG(pg_trigger,2620,TriggerRelationId)
35 {
36  Oid oid; /* oid */
37  Oid tgrelid; /* relation trigger is attached to */
38  Oid tgparentid; /* OID of parent trigger, if any */
39  NameData tgname; /* trigger's name */
40  Oid tgfoid; /* OID of function to be called */
41  int16 tgtype; /* BEFORE/AFTER/INSTEAD, UPDATE/DELETE/INSERT,
42  * ROW/STATEMENT; see below */
43  char tgenabled; /* trigger's firing configuration WRT
44  * session_replication_role */
45  bool tgisinternal; /* trigger is system-generated */
46  Oid tgconstrrelid; /* constraint's FROM table, if any */
47  Oid tgconstrindid; /* constraint's supporting index, if any */
48  Oid tgconstraint; /* associated pg_constraint entry, if any */
49  bool tgdeferrable; /* constraint trigger is deferrable */
50  bool tginitdeferred; /* constraint trigger is deferred initially */
51  int16 tgnargs; /* # of extra arguments in tgargs */
52 
53  /*
54  * Variable-length fields start here, but we allow direct access to
55  * tgattr. Note: tgattr and tgargs must not be null.
56  */
57  int2vector tgattr; /* column numbers, if trigger is on columns */
58 
59 #ifdef CATALOG_VARLEN
60  bytea tgargs BKI_FORCE_NOT_NULL; /* first\000second\000tgnargs\000 */
61  pg_node_tree tgqual; /* WHEN expression, or NULL if none */
62  NameData tgoldtable; /* old transition table, or NULL if none */
63  NameData tgnewtable; /* new transition table, or NULL if none */
64 #endif
66 
67 /* ----------------
68  * Form_pg_trigger corresponds to a pointer to a tuple with
69  * the format of pg_trigger relation.
70  * ----------------
71  */
73 
74 #ifdef EXPOSE_TO_CLIENT_CODE
75 
76 /* Bits within tgtype */
77 #define TRIGGER_TYPE_ROW (1 << 0)
78 #define TRIGGER_TYPE_BEFORE (1 << 1)
79 #define TRIGGER_TYPE_INSERT (1 << 2)
80 #define TRIGGER_TYPE_DELETE (1 << 3)
81 #define TRIGGER_TYPE_UPDATE (1 << 4)
82 #define TRIGGER_TYPE_TRUNCATE (1 << 5)
83 #define TRIGGER_TYPE_INSTEAD (1 << 6)
84 
85 #define TRIGGER_TYPE_LEVEL_MASK (TRIGGER_TYPE_ROW)
86 #define TRIGGER_TYPE_STATEMENT 0
87 
88 /* Note bits within TRIGGER_TYPE_TIMING_MASK aren't adjacent */
89 #define TRIGGER_TYPE_TIMING_MASK \
90  (TRIGGER_TYPE_BEFORE | TRIGGER_TYPE_INSTEAD)
91 #define TRIGGER_TYPE_AFTER 0
92 
93 #define TRIGGER_TYPE_EVENT_MASK \
94  (TRIGGER_TYPE_INSERT | TRIGGER_TYPE_DELETE | TRIGGER_TYPE_UPDATE | TRIGGER_TYPE_TRUNCATE)
95 
96 /* Macros for manipulating tgtype */
97 #define TRIGGER_CLEAR_TYPE(type) ((type) = 0)
98 
99 #define TRIGGER_SETT_ROW(type) ((type) |= TRIGGER_TYPE_ROW)
100 #define TRIGGER_SETT_STATEMENT(type) ((type) |= TRIGGER_TYPE_STATEMENT)
101 #define TRIGGER_SETT_BEFORE(type) ((type) |= TRIGGER_TYPE_BEFORE)
102 #define TRIGGER_SETT_AFTER(type) ((type) |= TRIGGER_TYPE_AFTER)
103 #define TRIGGER_SETT_INSTEAD(type) ((type) |= TRIGGER_TYPE_INSTEAD)
104 #define TRIGGER_SETT_INSERT(type) ((type) |= TRIGGER_TYPE_INSERT)
105 #define TRIGGER_SETT_DELETE(type) ((type) |= TRIGGER_TYPE_DELETE)
106 #define TRIGGER_SETT_UPDATE(type) ((type) |= TRIGGER_TYPE_UPDATE)
107 #define TRIGGER_SETT_TRUNCATE(type) ((type) |= TRIGGER_TYPE_TRUNCATE)
108 
109 #define TRIGGER_FOR_ROW(type) ((type) & TRIGGER_TYPE_ROW)
110 #define TRIGGER_FOR_BEFORE(type) (((type) & TRIGGER_TYPE_TIMING_MASK) == TRIGGER_TYPE_BEFORE)
111 #define TRIGGER_FOR_AFTER(type) (((type) & TRIGGER_TYPE_TIMING_MASK) == TRIGGER_TYPE_AFTER)
112 #define TRIGGER_FOR_INSTEAD(type) (((type) & TRIGGER_TYPE_TIMING_MASK) == TRIGGER_TYPE_INSTEAD)
113 #define TRIGGER_FOR_INSERT(type) ((type) & TRIGGER_TYPE_INSERT)
114 #define TRIGGER_FOR_DELETE(type) ((type) & TRIGGER_TYPE_DELETE)
115 #define TRIGGER_FOR_UPDATE(type) ((type) & TRIGGER_TYPE_UPDATE)
116 #define TRIGGER_FOR_TRUNCATE(type) ((type) & TRIGGER_TYPE_TRUNCATE)
117 
118 /*
119  * Efficient macro for checking if tgtype matches a particular level
120  * (TRIGGER_TYPE_ROW or TRIGGER_TYPE_STATEMENT), timing (TRIGGER_TYPE_BEFORE,
121  * TRIGGER_TYPE_AFTER or TRIGGER_TYPE_INSTEAD), and event (TRIGGER_TYPE_INSERT,
122  * TRIGGER_TYPE_DELETE, TRIGGER_TYPE_UPDATE, or TRIGGER_TYPE_TRUNCATE). Note
123  * that a tgtype can match more than one event, but only one level or timing.
124  */
125 #define TRIGGER_TYPE_MATCHES(type, level, timing, event) \
126  (((type) & (TRIGGER_TYPE_LEVEL_MASK | TRIGGER_TYPE_TIMING_MASK | (event))) == ((level) | (timing) | (event)))
127 
128 /*
129  * Macro to determine whether tgnewtable or tgoldtable has been specified for
130  * a trigger.
131  */
132 #define TRIGGER_USES_TRANSITION_TABLE(namepointer) \
133  ((namepointer) != (char *) NULL)
134 
135 #endif /* EXPOSE_TO_CLIENT_CODE */
136 
137 #endif /* PG_TRIGGER_H */
signed short int16
Definition: c.h:354
FormData_pg_trigger
Definition: pg_trigger.h:65
unsigned int Oid
Definition: postgres_ext.h:31
#define BKI_FORCE_NOT_NULL
Definition: genbki.h:33
Definition: c.h:609
CATALOG(pg_trigger, 2620, TriggerRelationId)
Definition: pg_trigger.h:34
Definition: c.h:583
FormData_pg_trigger * Form_pg_trigger
Definition: pg_trigger.h:72
Definition: c.h:555