src/include/commands/trigger.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * trigger.h
   4  *        Declarations for trigger handling.
   5  *
   6  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * $PostgreSQL$
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef TRIGGER_H
  14 #define TRIGGER_H
  15
  16 #include "nodes/execnodes.h"
  17 #include "nodes/parsenodes.h"
  18
  19 /*
  20  * TriggerData is the node type that is passed as fmgr "context" info
  21  * when a function is called by the trigger manager.
  22  */
  23
  24 #define CALLED_AS_TRIGGER(fcinfo) \
  25         ((fcinfo)->context != NULL && IsA((fcinfo)->context, TriggerData))
  26
  27 typedef uint32 TriggerEvent;
  28
  29 typedef struct TriggerData
  30 {
  31         NodeTag         type;
  32         TriggerEvent tg_event;
  33         Relation        tg_relation;
  34         HeapTuple       tg_trigtuple;
  35         HeapTuple       tg_newtuple;
  36         Trigger    *tg_trigger;
  37         Buffer          tg_trigtuplebuf;
  38         Buffer          tg_newtuplebuf;
  39 } TriggerData;
  40
  41 /*
  42  * TriggerEvent bit flags
  43  *
  44  * Note that we assume different event types (INSERT/DELETE/UPDATE/TRUNCATE)
  45  * can't be OR'd together in a single TriggerEvent.  This is unlike the
  46  * situation for pg_trigger rows, so pg_trigger.tgtype uses a different
  47  * representation!
  48  */
  49 #define TRIGGER_EVENT_INSERT                    0x00000000
  50 #define TRIGGER_EVENT_DELETE                    0x00000001
  51 #define TRIGGER_EVENT_UPDATE                    0x00000002
  52 #define TRIGGER_EVENT_TRUNCATE                  0x00000003
  53 #define TRIGGER_EVENT_OPMASK                    0x00000003
  54 #define TRIGGER_EVENT_ROW                               0x00000004
  55 #define TRIGGER_EVENT_BEFORE                    0x00000008
  56
  57 /* More TriggerEvent flags, used only within trigger.c */
  58
  59 #define AFTER_TRIGGER_DEFERRABLE                0x00000010
  60 #define AFTER_TRIGGER_INITDEFERRED              0x00000020
  61
  62 #define TRIGGER_FIRED_BY_INSERT(event)  \
  63                 (((TriggerEvent) (event) & TRIGGER_EVENT_OPMASK) == \
  64                                                                                                 TRIGGER_EVENT_INSERT)
  65
  66 #define TRIGGER_FIRED_BY_DELETE(event)  \
  67                 (((TriggerEvent) (event) & TRIGGER_EVENT_OPMASK) == \
  68                                                                                                 TRIGGER_EVENT_DELETE)
  69
  70 #define TRIGGER_FIRED_BY_UPDATE(event)  \
  71                 (((TriggerEvent) (event) & TRIGGER_EVENT_OPMASK) == \
  72                                                                                                 TRIGGER_EVENT_UPDATE)
  73
  74 #define TRIGGER_FIRED_BY_TRUNCATE(event) \
  75                 (((TriggerEvent) (event) & TRIGGER_EVENT_OPMASK) == \
  76                                                                                                 TRIGGER_EVENT_TRUNCATE)
  77
  78 #define TRIGGER_FIRED_FOR_ROW(event)                    \
  79                 ((TriggerEvent) (event) & TRIGGER_EVENT_ROW)
  80
  81 #define TRIGGER_FIRED_FOR_STATEMENT(event)              \
  82                 (!TRIGGER_FIRED_FOR_ROW (event))
  83
  84 #define TRIGGER_FIRED_BEFORE(event)                             \
  85                 ((TriggerEvent) (event) & TRIGGER_EVENT_BEFORE)
  86
  87 #define TRIGGER_FIRED_AFTER(event)                              \
  88                 (!TRIGGER_FIRED_BEFORE (event))
  89
  90 /*
  91  * Definitions for the replication role based firing.
  92  */
  93 #define SESSION_REPLICATION_ROLE_ORIGIN         0
  94 #define SESSION_REPLICATION_ROLE_REPLICA        1
  95 #define SESSION_REPLICATION_ROLE_LOCAL          2
  96 extern PGDLLIMPORT int SessionReplicationRole;
  97
  98 /*
  99  * States at which a trigger can be fired. These are the
 100  * possible values for pg_trigger.tgenabled.
 101  */
 102 #define TRIGGER_FIRES_ON_ORIGIN                         'O'
 103 #define TRIGGER_FIRES_ALWAYS                            'A'
 104 #define TRIGGER_FIRES_ON_REPLICA                        'R'
 105 #define TRIGGER_DISABLED                                        'D'
 106
 107 extern Oid CreateTrigger(CreateTrigStmt *stmt, Oid constraintOid,
 108                           bool checkPermissions);
 109
 110 extern void DropTrigger(Oid relid, const char *trigname,
 111                         DropBehavior behavior, bool missing_ok);
 112 extern void RemoveTriggerById(Oid trigOid);
 113
 114 extern void renametrig(Oid relid, const char *oldname, const char *newname);
 115
 116 extern void EnableDisableTrigger(Relation rel, const char *tgname,
 117                                          char fires_when, bool skip_system);
 118
 119 extern void RelationBuildTriggers(Relation relation);
 120
 121 extern TriggerDesc *CopyTriggerDesc(TriggerDesc *trigdesc);
 122
 123 extern void FreeTriggerDesc(TriggerDesc *trigdesc);
 124
 125 extern void ExecBSInsertTriggers(EState *estate,
 126                                          ResultRelInfo *relinfo);
 127 extern void ExecASInsertTriggers(EState *estate,
 128                                          ResultRelInfo *relinfo);
 129 extern HeapTuple ExecBRInsertTriggers(EState *estate,
 130                                          ResultRelInfo *relinfo,
 131                                          HeapTuple trigtuple);
 132 extern void ExecARInsertTriggers(EState *estate,
 133                                          ResultRelInfo *relinfo,
 134                                          HeapTuple trigtuple);
 135 extern void ExecBSDeleteTriggers(EState *estate,
 136                                          ResultRelInfo *relinfo);
 137 extern void ExecASDeleteTriggers(EState *estate,
 138                                          ResultRelInfo *relinfo);
 139 extern bool ExecBRDeleteTriggers(EState *estate,
 140                                          ResultRelInfo *relinfo,
 141                                          ItemPointer tupleid);
 142 extern void ExecARDeleteTriggers(EState *estate,
 143                                          ResultRelInfo *relinfo,
 144                                          ItemPointer tupleid);
 145 extern void ExecBSUpdateTriggers(EState *estate,
 146                                          ResultRelInfo *relinfo);
 147 extern void ExecASUpdateTriggers(EState *estate,
 148                                          ResultRelInfo *relinfo);
 149 extern HeapTuple ExecBRUpdateTriggers(EState *estate,
 150                                          ResultRelInfo *relinfo,
 151                                          ItemPointer tupleid,
 152                                          HeapTuple newtuple);
 153 extern void ExecARUpdateTriggers(EState *estate,
 154                                          ResultRelInfo *relinfo,
 155                                          ItemPointer tupleid,
 156                                          HeapTuple newtuple);
 157 extern void ExecBSTruncateTriggers(EState *estate,
 158                                            ResultRelInfo *relinfo);
 159 extern void ExecASTruncateTriggers(EState *estate,
 160                                            ResultRelInfo *relinfo);
 161
 162 extern void AfterTriggerBeginXact(void);
 163 extern void AfterTriggerBeginQuery(void);
 164 extern void AfterTriggerEndQuery(EState *estate);
 165 extern void AfterTriggerFireDeferred(void);
 166 extern void AfterTriggerEndXact(bool isCommit);
 167 extern void AfterTriggerBeginSubXact(void);
 168 extern void AfterTriggerEndSubXact(bool isCommit);
 169 extern void AfterTriggerSetState(ConstraintsSetStmt *stmt);
 170 extern bool AfterTriggerPendingOnRel(Oid relid);
 171
 172
 173 /*
 174  * in utils/adt/ri_triggers.c
 175  */
 176 extern bool RI_FKey_keyequal_upd_pk(Trigger *trigger, Relation pk_rel,
 177                                                 HeapTuple old_row, HeapTuple new_row);
 178 extern bool RI_FKey_keyequal_upd_fk(Trigger *trigger, Relation fk_rel,
 179                                                 HeapTuple old_row, HeapTuple new_row);
 180 extern bool RI_Initial_Check(Trigger *trigger,
 181                                  Relation fk_rel, Relation pk_rel);
 182
 183 /* result values for RI_FKey_trigger_type: */
 184 #define RI_TRIGGER_PK   1               /* is a trigger on the PK relation */
 185 #define RI_TRIGGER_FK   2               /* is a trigger on the FK relation */
 186 #define RI_TRIGGER_NONE 0               /* is not an RI trigger function */
 187
 188 extern int      RI_FKey_trigger_type(Oid tgfoid);
 189
 190 #endif   /* TRIGGER_H */