Drop statement is not included in the Rebuild Trigger script
In v5.6, when rebuilding a trigger in the Explorer, there is not a drop statement at the beginning of the script that is created. It is just a Create or Replace statement. In previous versions, it had a drop statement at the beginning of the script.
This change was made because generating using CREATE OR REPLACE is more efficient as DB2 will take care of creating or replacing the object and will handle the authorization keeping any intact. Customers requested that we use CREATE OR REPLACE whenever we can because it is more efficient. The DROP statement was there in early releases because logic was based on older releases of DB2 that did not support CREATE OR REPLACE.
STATUS: Waiting for enhancement request ID 'TDB-1577' to be implemented in a future version of Toad for DB2.