On 7 Aug 2010, at 23:18, Thomas Kellerer wrote: > Or as an alternative: > > SELECT tid, purchase_date > FROM orders > WHERE item in ('Laptop', 'Desktop') > GROUP BY tid, purchase_date > HAVING count(*) = 2
This one is incorrect, it will also find people who bought two laptops or two desktops on the same date. I was going to suggest: SELECT tid, "date", 001::bit as type FROM orders WHERE item = 'Laptop' UNION ALL SELECT tid, "date", 010::bit as type FROM orders WHERE item = 'Desktop' GROUP BY tid, "date" HAVING type & 011::bit = 011::bit; But I think David's solution is more readable, as it leaves the item names in tact. Alban Hertroys -- If you can't see the forest for the trees, cut the trees and you'll see there is no forest. !DSPAM:737,4c5e6ee4286211665369939! -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general