Syntax
------

SHOW TRIGGERS [FROM db_name]
  [LIKE 'pattern' | WHERE expr]

Description
-----------

SHOW TRIGGERS lists the triggers currently defined for tables in a database
(the default database unless a FROM clause is given). This statement requires
the TRIGGER privilege (prior to MySQL 5.1.22, it required the SUPER privilege).

The LIKE clause, if present on its own, indicates which table names to match
and causes the statement to display triggers for those tables. The WHERE and
LIKE clauses can be given to select rows using more general conditions, as
discussed in Extended SHOW.

Similar information is stored in the information_schema.TRIGGERS table.

MariaDB starting with 10.2.3
----------------------------
If there are multiple triggers for the same action, then the triggers are
shown in action order.

Examples
--------

For the trigger defined at Trigger Overview:

SHOW triggers Like 'animals' \G
*************************** 1. row ***************************
      Trigger: the_mooses_are_loose
       Event: INSERT
       Table: animals
     Statement: BEGIN
 IF NEW.name = 'Moose' THEN
 UPDATE animal_count SET animal_count.animals = animal_count.animals+100;
 ELSE 
 UPDATE animal_count SET animal_count.animals = animal_count.animals+1;
 END IF;
END
       Timing: AFTER
      Created: 2016-09-29 13:53:34.35
      sql_mode:
      Definer: root@localhost
character_set_client: utf8
collation_connection: utf8_general_ci
 Database Collation: latin1_swedish_ci

Listing all triggers associated with a certain table:

SHOW TRIGGERS FROM test WHERE `Table` = 'user' \G
*************************** 1. row ***************************
      Trigger: user_ai
       Event: INSERT
       Table: user
     Statement: BEGIN END
       Timing: AFTER
      Created:  2016-09-29 13:53:34.35
      sql_mode:
      Definer: root@%
character_set_client: utf8
collation_connection: utf8_general_ci
 Database Collation: latin1_swedish_ci

SHOW triggers WHERE Event Like 'Insert' \G
*************************** 1. row ***************************
      Trigger: the_mooses_are_loose
       Event: INSERT
       Table: animals
     Statement: BEGIN
 IF NEW.name = 'Moose' THEN
 UPDATE animal_count SET animal_count.animals = animal_count.animals+100;
 ELSE 
 UPDATE animal_count SET animal_count.animals = animal_count.animals+1;
 END IF;
END
       Timing: AFTER
      Created: 2016-09-29 13:53:34.35
      sql_mode:
      Definer: root@localhost
character_set_client: utf8
collation_connection: utf8_general_ci
 Database Collation: latin1_swedish_ci

* character_set_client is the session value of the character_set_client system
variable when the trigger was created. 
* collation_connection is the session value of the collation_connection system
variable when the trigger was
 created. 
* Database Collation is the collation of the database 
 with which the trigger is associated.

These columns were added in MariaDB/MySQL 5.1.21.

Old triggers created before MySQL 5.7 and MariaDB 10.2.3 has NULL in the
Created column.

URL: https://mariadb.com/kb/en/show-triggers/