ALTER TRIGGER Syntax Elements - Advanced SQL Engine

database_name: Name of the database containing the trigger definition if not the default database for the trigger_name or table_name.
user_name: Name of the user containing the trigger definition if not the default database for the trigger_name or table_name.
trigger_name: The name of the trigger to be altered.  If you specify trigger_name you can alter only one trigger at a time.
ENABLED: The named trigger or all triggers on the named table are to be enabled.  Enabled triggers function as active database objects and follow normal trigger protocol. 
DISABLED: The named trigger or all triggers on the named table are to be disabled. Disabled triggers continue to exist as database objects, but cannot execute. For a trigger to execute, it must first be enabled.
TIMESTAMP: The creation timestamp of the named trigger is to be replaced with the current timestamp.  Altering the creation timestamp of a trigger changes its position in the default order of execution, when multiple triggers are defined on a table.; The TIMESTAMP option does not apply to a table.; You can use the TIMESTAMP option to change the order of execution of triggers, particularly triggers that were created without the ORDER clause. If you do not specify a TIMESTAMP, then the existing timestamp for the trigger is not changed.; ALTER TRIGGER uses the current time when adding a timestamp. To change the timings for multiple order-sensitive triggers defined on the same table, you must submit ALTER TRIGGER statements that change the timestamps in the required order to ensure the correct execution precedence.
table_name: The name of the table on which triggers are to be enabled or disabled.

ALTER TRIGGER Syntax Elements - Advanced SQL Engine - Teradata Database

SQL Data Definition Language Syntax and Examples