Hello, I have added some default values and foreign key constraints to a postgres based otrs database. After importing the attached file - your database will enforce these constraints. It will be safe to delete tickets, users, queues using sql statements. The create_by and change_by columns will be reset to their default id=1 (root@localhost) which means that you cannot remove the user with id=1 but you can remove all other users if you want. Please just read the file to get a feeling which things will become possible. ;-) Note that the initial_insert.sql from otrs version 1.2.3 is not error free. :-( You cannot apply the attached file without correcting the database content first. That is why I do not recommend applying my changes to a production system. Otherwise the file should work with other databases that support foreign key constraints like postgres. But mysql is probably not good enough. Best Regards, Torsten