1) Yes All rows are treated the same, there are no in place updates.
2) No Truncate recreates the object as a new one, releasing the space held by the old one. - Luke Msg is shrt cuz m on ma treo -----Original Message----- From: Scott Feldstein [mailto:[EMAIL PROTECTED] Sent: Thursday, July 26, 2007 06:44 PM Eastern Standard Time To: pgsql-performance@postgresql.org Subject: [PERFORM] update, truncate and vacuum Hi, I have a couple questions about how update, truncate and vacuum would work together. 1) If I update a table foo (id int, value numeric (20, 6)) with update foo set value = 100 where id = 1 Would a vacuum be necessary after this type of operation since the updated value is a numeric? (as opposed to a sql type where its size could potentially change i.e varchar) 2) After several updates/deletes to a table, if I truncate it, would it be necessary to run vacuum in order to reclaim the space? thanks, Scott ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
