pg_trigger
   The catalog pg_trigger stores triggers on tables
   and views.
   See CREATE TRIGGER
   for more information.
  
Table 52.56. pg_trigger Columns
| Column Type Description | 
|---|
| 
        Row identifier | 
| 
        The table this trigger is on | 
| 
        Parent trigger that this trigger is cloned from (this happens when partitions are created or attached to a partitioned table); zero if not a clone | 
| 
        Trigger name (must be unique among triggers of same table) | 
| 
        The function to be called | 
| 
        Bit mask identifying trigger firing conditions | 
| 
        
       Controls in which session_replication_role modes
       the trigger fires.
        | 
| 
        
       True if trigger is internally generated (usually, to enforce
       the constraint identified by  | 
| 
        The table referenced by a referential integrity constraint (zero if trigger is not for a referential integrity constraint) | 
| 
        The index supporting a unique, primary key, referential integrity, or exclusion constraint (zero if trigger is not for one of these types of constraint) | 
| 
        
       The  | 
| 
        True if constraint trigger is deferrable | 
| 
        True if constraint trigger is initially deferred | 
| 
        Number of argument strings passed to trigger function | 
| 
        Column numbers, if trigger is column-specific; otherwise an empty array | 
| 
        Argument strings to pass to trigger, each NULL-terminated | 
| 
        
       Expression tree (in  | 
| 
        
        | 
| 
        
        | 
   Currently, column-specific triggering is supported only for
   UPDATE events, and so tgattr is relevant
   only for that event type.  tgtype might
   contain bits for other event types as well, but those are presumed
   to be table-wide regardless of what is in tgattr.
  
    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: foreign key constraints can have some
    deferrable and some non-deferrable triggers.
   
    pg_class.relhastriggers
    must be true if a relation has any triggers in this catalog.