The view triggers contains all triggers defined in the current database that are owned by the current user. (The owner of the table is the owner of the trigger.)
Table 32-35. triggers Columns
Name
Data Type
Description
trigger_catalog
sql_identifier
Name of the database that contains the trigger (always the current database)
trigger_schema
sql_identifier
Name of the schema that contains the trigger
trigger_name
sql_identifier
Name of the trigger
event_manipulation
character_data
Event that fires the trigger (INSERT, UPDATE, or DELETE)
event_object_catalog
sql_identifier
Name of the database that contains the table that the trigger is defined on (always the current database)
event_object_schema
sql_identifier
Name of the schema that contains the table that the trigger is defined on
event_object_name
sql_identifier
Name of the table that the trigger is defined on
action_order
cardinal_number
Not yet implemented
action_condition
character_data
Applies to a feature not available in PostgreSQL
action_statement
character_data
Statement that is executed by the trigger (currently always EXECUTE PROCEDURE function(...))
action_orientation
character_data
Identifies whether the trigger fires once for each processed row or once for each statement (ROW or STATEMENT)
condition_timing
character_data
Time at which the trigger fires (BEFORE or AFTER)
condition_reference_old_table
sql_identifier
Applies to a feature not available in PostgreSQL
condition_reference_new_table
sql_identifier
Applies to a feature not available in PostgreSQL
Triggers in PostgreSQL have two incompatibilities with the SQL standard that affect the representation in the information schema. First, trigger names are local to the table in PostgreSQL, rather than independent schema objects. Therefore there may be duplicate trigger names defined in one schema, as long as they belong to different tables. (trigger_catalog and trigger_schema are really the values pertaining to the table that the trigger is defined on.) Second, triggers can be defined to fire on multiple events in PostgreSQL (e.g., ON INSERT OR UPDATE), whereas the SQL standard only allows one. If a trigger is defined to fire on multiple events, it is represented as multiple rows in the information schema, one for each type of event. As a consequence of these two issues, the primary key of the view triggers is really (trigger_catalog, trigger_schema, trigger_name, event_object_name, event_manipulation) instead of (trigger_catalog, trigger_schema, trigger_name), which is what the SQL standard specifies. Nonetheless, if you define your triggers in a manner that conforms with the SQL standard (trigger names unique in the schema and only one event type per trigger), this will not affect you.
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