Instead, say that “If we take a week to add referential integrity and foreign keys to the database, we’ll make coding safer, and will probably cut down on errors. Remember that Foo project and we blew the deadline by two weeks because we had an extra three weeks of bugs that we had to close? Most of that was caused by bugs that would have been caught if we’d had foreign key constraints in place. We want to prevent future screwups like that.” That’s a story that your boss can get behind, and one that he can explain to his boss, too.