On 8/10/07, Raymond O'Donnell <[EMAIL PROTECTED]> wrote: > - how can I find those people who don't have _all_ of the items which > are marked "required"? > > In other words, how do I select those rows in "people" which don't have > a corresponding row in "items_for_people" for *each* row in "items" > which has is_required=true?
Without writing the exact query you need, I'll give you a couple of ways to solve the problem of finding things in one set that aren't in another. select table1.id from table1 left join table2 on (table1.id=table2.id) where table2.id is null OR select table1.id from table1 where table1.id is not in (select id from table2); ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
