1  –  COMMENT_IS

    Adds a comment about the trigger. SQL displays the text of the
    comment when it executes a SHOW statement. Enclose the comment
    in single quotation marks ( ') and separate multiple lines in a
    comment with a slash mark (/).

2  –  DISABLE

    Disables a previously enabled trigger.

3  –  ENABLE

    Enables a previously disabled trigger.

4  –  RENAME_TO

    Changes the name of the trigger being altered. See the RENAME for
    further discussion. If the new name is the name of a synonym then
    an error will be raised.

    The RENAME TO clause requires synonyms be enabled for this
    database. Refer to the ALTER DATABASE statement SYNONYMS ARE
    ENABLED clause. Note that these synonyms may be deleted if they
    are no longer used by database definitions or applications.

5  –  trigger-name

    The name of an existing trigger.