MySQL 9.3 Reference Manual Including MySQL NDB Cluster 9.3
The TRIGGERS
table provides
information about triggers. To see information about a table's
triggers, you must have the TRIGGER
privilege for the table.
The TRIGGERS
table has these columns:
TRIGGER_CATALOG
The name of the catalog to which the trigger belongs. This
value is always def
.
TRIGGER_SCHEMA
The name of the schema (database) to which the trigger belongs.
TRIGGER_NAME
The name of the trigger.
EVENT_MANIPULATION
The trigger event. This is the type of operation on the
associated table for which the trigger activates. The value is
INSERT
(a row was inserted),
DELETE
(a row was deleted), or
UPDATE
(a row was modified).
EVENT_OBJECT_CATALOG
,
EVENT_OBJECT_SCHEMA
, and
EVENT_OBJECT_TABLE
As noted in Section 27.4, “Using Triggers”, every trigger is
associated with exactly one table. These columns indicate the
catalog and schema (database) in which this table occurs, and
the table name, respectively. The
EVENT_OBJECT_CATALOG
value is always
def
.
ACTION_ORDER
The ordinal position of the trigger's action within the list
of triggers on the same table with the same
EVENT_MANIPULATION
and
ACTION_TIMING
values.
ACTION_CONDITION
This value is always NULL
.
ACTION_STATEMENT
The trigger body; that is, the statement executed when the trigger activates. This text uses UTF-8 encoding.
ACTION_ORIENTATION
This value is always ROW
.
ACTION_TIMING
Whether the trigger activates before or after the triggering
event. The value is BEFORE
or
AFTER
.
ACTION_REFERENCE_OLD_TABLE
This value is always NULL
.
ACTION_REFERENCE_NEW_TABLE
This value is always NULL
.
ACTION_REFERENCE_OLD_ROW
and
ACTION_REFERENCE_NEW_ROW
The old and new column identifiers, respectively. The
ACTION_REFERENCE_OLD_ROW
value is always
OLD
and the
ACTION_REFERENCE_NEW_ROW
value is always
NEW
.
CREATED
The date and time when the trigger was created. This is a
TIMESTAMP(2)
value (with a fractional part
in hundredths of seconds) for triggers.
SQL_MODE
The SQL mode in effect when the trigger was created, and under which the trigger executes. For the permitted values, see Section 7.1.11, “Server SQL Modes”.
DEFINER
The account named in the DEFINER
clause
(often the user who created the trigger), in
'
format.
user_name
'@'host_name
'
CHARACTER_SET_CLIENT
The session value of the
character_set_client
system
variable when the trigger was created.
COLLATION_CONNECTION
The session value of the
collation_connection
system
variable when the trigger was created.
DATABASE_COLLATION
The collation of the database with which the trigger is associated.
The following example uses the ins_sum
trigger
defined in Section 27.4, “Using Triggers”:
mysql>SELECT * FROM INFORMATION_SCHEMA.TRIGGERS
WHERE TRIGGER_SCHEMA='test' AND TRIGGER_NAME='ins_sum'\G
*************************** 1. row *************************** TRIGGER_CATALOG: def TRIGGER_SCHEMA: test TRIGGER_NAME: ins_sum EVENT_MANIPULATION: INSERT EVENT_OBJECT_CATALOG: def EVENT_OBJECT_SCHEMA: test EVENT_OBJECT_TABLE: account ACTION_ORDER: 1 ACTION_CONDITION: NULL ACTION_STATEMENT: SET @sum = @sum + NEW.amount ACTION_ORIENTATION: ROW ACTION_TIMING: BEFORE ACTION_REFERENCE_OLD_TABLE: NULL ACTION_REFERENCE_NEW_TABLE: NULL ACTION_REFERENCE_OLD_ROW: OLD ACTION_REFERENCE_NEW_ROW: NEW CREATED: 2018-08-08 10:10:12.61 SQL_MODE: ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES, NO_ZERO_IN_DATE,NO_ZERO_DATE, ERROR_FOR_DIVISION_BY_ZERO, NO_ENGINE_SUBSTITUTION DEFINER: me@localhost CHARACTER_SET_CLIENT: utf8mb4 COLLATION_CONNECTION: utf8mb4_0900_ai_ci DATABASE_COLLATION: utf8mb4_0900_ai_ci
Trigger information is also available from the
SHOW TRIGGERS
statement. See
Section 15.7.7.41, “SHOW TRIGGERS Statement”.