DROP TRIGGER [schema_name.]trigger_name
This statement drops a trigger. The schema (database) name is
optional. If the schema is omitted, the trigger is dropped from
the default schema. DROP TRIGGER was added in
MySQL 5.0.2. Its use requires the SUPER
privilege.
Note: Prior to MySQL 5.0.10, the
table name was required instead of the schema name
(table_name.trigger_name).
When upgrading from a previous version of MySQL 5.0 to MySQL
5.0.10 or newer, you must drop all triggers before
upgrading and re-create them afterwards, or else
DROP TRIGGER does not work after the upgrade.
See Section 2.11.2, “Upgrading from MySQL 4.1 to 5.0”, for a suggested upgrade
procedure.
In addition, triggers created in MySQL 5.0.16 or later cannot be dropped following a downgrade to MySQL 5.0.15 or earlier. If you wish to perform such a downgrade, you must also in this case drop all triggers prior to the downgrade, and then re-create them afterwards.
(For more information about these two issues, see Bug #15921 and Bug #18588.)