Actually your question is a very good one. Most brands of SQL have numerous extensions that go beyond the ANSI standards. The purpose of this forum is to provide answers in fairly generic SQL, to provide for portability across platforms. In practice, however, we acknowledge that this isn't always possible. Frequently, the non-ANSI solution is by far the best way of doing something. That's why a lot of responses include a disclaimer like "it depends on which dbms you're using".