When a delete statement on titles is executed, one or more rows leave the titles table and are added to deleted. A trigger can check the dependent tables—titleauthor, salesdetail, and roysched—to see if they have any rows with a title_id that matches the title_ids removed from titles and is now stored in the deleted table. If the trigger finds any such rows, it removes them.
create trigger delcascadetrig on titles for delete as delete titleauthor from titleauthor, deleted where titleauthor.title_id = deleted.title_id /* Remove titleauthor rows that match deleted ** (titles) rows.*/ delete salesdetail from salesdetail, deleted where salesdetail.title_id = deleted.title_id /* Remove salesdetail rows that match deleted ** (titles) rows.*/ delete roysched from roysched, deleted where roysched.title_id = deleted.title_id /* Remove roysched rows that match deleted ** (titles) rows.*/
