Reac-Cache-Rate of a Data Warehousing System

Have a couple questions here, In the Informix Performance Guide, a >95% read cache rate is normal and definitely achievable in a transactional system/environment. Considering the vast amount of data read/written in a data warehousing system, is it practical having the BUFFERS the size of the huge amount data read by a query statement? On the same light, is achieving >95% read cache rate on such a system practical? thanks in advance leekb@bigfoot.com Sent via Deja.com http://www.deja.com/ Before you buy.