DROP EVENT [IF EXISTS] event_name
This statement drops the event named event_name. The event immediately
ceases being active, and is deleted completely from the server.
If the event does not exist, the error ERROR 1517 (HY000): Unknown
event 'event_name' results. You can override this and cause the
statement to generate a warning for nonexistent events instead using IF
This statement requires the EVENT privilege for the schema to which the
event to be dropped belongs.