[thelist] DB Design question
rudy
rudy937 at rogers.com
Mon Sep 15 15:53:16 CDT 2003
> what about querying for inactive records?
select a.id
from a
left outer
join b
on a.id = b.id
where b.id is null
> And wouldn't that be more expensive to compute?
no, not really, no more so than your typical outer join
granted, outer joins might be slightly more expensive than inner joins, but
not by a whole heck of a lot
besides, since this extra table contains only ids, the concept of "join" is
pretty nebulous, since the optimizer will not be accessing tables at all,
just indexes
rudy
More information about the thelist
mailing list