pg_trigger.h

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/*-------------------------------------------------------------------------
 *
 * pg_trigger.h
 *    definition of the "trigger" system catalog (pg_trigger)
 *
 *
 * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/catalog/pg_trigger.h
 *
 * NOTES
 *    The Catalog.pm module reads this file and derives schema
 *    information.
 *
 *-------------------------------------------------------------------------
 */
#ifndef PG_TRIGGER_H
#define PG_TRIGGER_H
 
#include "catalog/genbki.h"
#include "catalog/pg_trigger_d.h"
 
/* ----------------
 *      pg_trigger definition.  cpp turns this into
 *      typedef struct FormData_pg_trigger
 *
 * Note: when tgconstraint is nonzero, tgconstrrelid, tgconstrindid,
 * tgdeferrable, and tginitdeferred are largely redundant with the referenced
 * pg_constraint entry.  However, it is possible for a non-deferrable trigger
 * to be associated with a deferrable constraint.
 * ----------------
 */
CATALOG(pg_trigger,2620,TriggerRelationId)
{
    Oid         oid;            /* oid */
    Oid         tgrelid BKI_LOOKUP(pg_class);   /* relation trigger is
                                                 * attached to */
    Oid         tgparentid BKI_LOOKUP_OPT(pg_trigger);  /* OID of parent
                                                         * trigger, if any */
    NameData    tgname;         /* trigger's name */
    Oid         tgfoid BKI_LOOKUP(pg_proc); /* OID of function to be called */
    int16       tgtype;         /* BEFORE/AFTER/INSTEAD, UPDATE/DELETE/INSERT,
                                 * ROW/STATEMENT; see below */
    char        tgenabled;      /* trigger's firing configuration WRT
                                 * session_replication_role */
    bool        tgisinternal;   /* trigger is system-generated */
    Oid         tgconstrrelid BKI_LOOKUP_OPT(pg_class); /* constraint's FROM
                                                         * table, if any */
    Oid         tgconstrindid BKI_LOOKUP_OPT(pg_class); /* constraint's
                                                         * supporting index, if
                                                         * any */
    Oid         tgconstraint BKI_LOOKUP_OPT(pg_constraint); /* associated
                                                             * pg_constraint entry,
                                                             * if any */
    bool        tgdeferrable;   /* constraint trigger is deferrable */
    bool        tginitdeferred; /* constraint trigger is deferred initially */
    int16       tgnargs;        /* # of extra arguments in tgargs */
 
    /*
     * Variable-length fields start here, but we allow direct access to
     * tgattr. Note: tgattr and tgargs must not be null.
     */
    int2vector  tgattr BKI_FORCE_NOT_NULL;  /* column numbers, if trigger is
                                             * on columns */
 
#ifdef CATALOG_VARLEN
    bytea       tgargs BKI_FORCE_NOT_NULL;  /* first\000second\000tgnargs\000 */
    pg_node_tree tgqual;        /* WHEN expression, or NULL if none */
    NameData    tgoldtable;     /* old transition table, or NULL if none */
    NameData    tgnewtable;     /* new transition table, or NULL if none */
#endif
} FormData_pg_trigger;
 
/* ----------------
 *      Form_pg_trigger corresponds to a pointer to a tuple with
 *      the format of pg_trigger relation.
 * ----------------
 */
typedef FormData_pg_trigger *Form_pg_trigger;
 
DECLARE_TOAST(pg_trigger, 2336, 2337);
 
DECLARE_INDEX(pg_trigger_tgconstraint_index, 2699, TriggerConstraintIndexId, pg_trigger, btree(tgconstraint oid_ops));
DECLARE_UNIQUE_INDEX(pg_trigger_tgrelid_tgname_index, 2701, TriggerRelidNameIndexId, pg_trigger, btree(tgrelid oid_ops, tgname name_ops));
DECLARE_UNIQUE_INDEX_PKEY(pg_trigger_oid_index, 2702, TriggerOidIndexId, pg_trigger, btree(oid oid_ops));
 
DECLARE_ARRAY_FOREIGN_KEY((tgrelid, tgattr), pg_attribute, (attrelid, attnum));
 
#ifdef EXPOSE_TO_CLIENT_CODE
 
/* Bits within tgtype */
#define TRIGGER_TYPE_ROW                (1 << 0)
#define TRIGGER_TYPE_BEFORE             (1 << 1)
#define TRIGGER_TYPE_INSERT             (1 << 2)
#define TRIGGER_TYPE_DELETE             (1 << 3)
#define TRIGGER_TYPE_UPDATE             (1 << 4)
#define TRIGGER_TYPE_TRUNCATE           (1 << 5)
#define TRIGGER_TYPE_INSTEAD            (1 << 6)
 
#define TRIGGER_TYPE_LEVEL_MASK         (TRIGGER_TYPE_ROW)
#define TRIGGER_TYPE_STATEMENT          0
 
/* Note bits within TRIGGER_TYPE_TIMING_MASK aren't adjacent */
#define TRIGGER_TYPE_TIMING_MASK \
    (TRIGGER_TYPE_BEFORE | TRIGGER_TYPE_INSTEAD)
#define TRIGGER_TYPE_AFTER              0
 
#define TRIGGER_TYPE_EVENT_MASK \
    (TRIGGER_TYPE_INSERT | TRIGGER_TYPE_DELETE | TRIGGER_TYPE_UPDATE | TRIGGER_TYPE_TRUNCATE)
 
/* Macros for manipulating tgtype */
#define TRIGGER_CLEAR_TYPE(type)        ((type) = 0)
 
#define TRIGGER_SETT_ROW(type)          ((type) |= TRIGGER_TYPE_ROW)
#define TRIGGER_SETT_STATEMENT(type)    ((type) |= TRIGGER_TYPE_STATEMENT)
#define TRIGGER_SETT_BEFORE(type)       ((type) |= TRIGGER_TYPE_BEFORE)
#define TRIGGER_SETT_AFTER(type)        ((type) |= TRIGGER_TYPE_AFTER)
#define TRIGGER_SETT_INSTEAD(type)      ((type) |= TRIGGER_TYPE_INSTEAD)
#define TRIGGER_SETT_INSERT(type)       ((type) |= TRIGGER_TYPE_INSERT)
#define TRIGGER_SETT_DELETE(type)       ((type) |= TRIGGER_TYPE_DELETE)
#define TRIGGER_SETT_UPDATE(type)       ((type) |= TRIGGER_TYPE_UPDATE)
#define TRIGGER_SETT_TRUNCATE(type)     ((type) |= TRIGGER_TYPE_TRUNCATE)
 
#define TRIGGER_FOR_ROW(type)           ((type) & TRIGGER_TYPE_ROW)
#define TRIGGER_FOR_BEFORE(type)        (((type) & TRIGGER_TYPE_TIMING_MASK) == TRIGGER_TYPE_BEFORE)
#define TRIGGER_FOR_AFTER(type)         (((type) & TRIGGER_TYPE_TIMING_MASK) == TRIGGER_TYPE_AFTER)
#define TRIGGER_FOR_INSTEAD(type)       (((type) & TRIGGER_TYPE_TIMING_MASK) == TRIGGER_TYPE_INSTEAD)
#define TRIGGER_FOR_INSERT(type)        ((type) & TRIGGER_TYPE_INSERT)
#define TRIGGER_FOR_DELETE(type)        ((type) & TRIGGER_TYPE_DELETE)
#define TRIGGER_FOR_UPDATE(type)        ((type) & TRIGGER_TYPE_UPDATE)
#define TRIGGER_FOR_TRUNCATE(type)      ((type) & TRIGGER_TYPE_TRUNCATE)
 
/*
 * Efficient macro for checking if tgtype matches a particular level
 * (TRIGGER_TYPE_ROW or TRIGGER_TYPE_STATEMENT), timing (TRIGGER_TYPE_BEFORE,
 * TRIGGER_TYPE_AFTER or TRIGGER_TYPE_INSTEAD), and event (TRIGGER_TYPE_INSERT,
 * TRIGGER_TYPE_DELETE, TRIGGER_TYPE_UPDATE, or TRIGGER_TYPE_TRUNCATE).  Note
 * that a tgtype can match more than one event, but only one level or timing.
 */
#define TRIGGER_TYPE_MATCHES(type, level, timing, event) \
    (((type) & (TRIGGER_TYPE_LEVEL_MASK | TRIGGER_TYPE_TIMING_MASK | (event))) == ((level) | (timing) | (event)))
 
/*
 * Macro to determine whether tgnewtable or tgoldtable has been specified for
 * a trigger.
 */
#define TRIGGER_USES_TRANSITION_TABLE(namepointer) \
    ((namepointer) != (char *) NULL)
 
#endif                          /* EXPOSE_TO_CLIENT_CODE */
 
#endif                          /* PG_TRIGGER_H */