=?UTF-8?B?6auY5YGl?= <luckyjackgao@xxxxxxxxx> writes: > It might not be a big problem in a small system. > But when in a production environment, When I want to use explain and > then , soon use explain analyze for the same statement, > How can I avoid the influence of cache and get the right answer for > evaluating purpose? I think this question is based on a false premise. Why do you feel that the behavior with cold caches is "the right answer", and not the behavior with warm caches? A short-duration query like this one is not going to be interesting at all for performance unless it's executed quite a lot, and if it's executed quite a lot then the warm-cache result ought to be the more representative one. In general, trying to tune for cold-cache cases seems backwards to me. It's much more productive to try to ensure that the caches are warm. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
