> It's possible to combine independent indexes for resolving AND-type > queries, but the combination process does not preserve ordering, so > it's useless for this type of situation. Ok, I'm going to try the double column index. Your suggestion about the index with nulls left out worked great btw. Min/Max is instantly now. I figure though that the double column index would not work for queries like: select min(time) from transactions where payment_id is null So for that situation I tried whether a specific index helped, i.e. : create index transactions__time_payment_id__null__idx on transactions(time) where payment_id is null; But this does not really seem to help. It might be better to see if I can refactor the DB design though to not use nulls. Regards Express yourself instantly with MSN Messenger! MSN Messenger |