> An unrestricted update will end up rewriting the whole table. > It's advisable to run VACUUM afterward, so that the wasted > space can be reclaimed. What version are you on? Do you have > autovacuum enabled? > > Also, to take a step back, why do you try to keep the > timestamps changing like that? Why not store the information > you need in the record (e.g. insert time as well as the > datum) and then compute the result you need using a SELECT > (or make it a view for convenience)? Fundamentally, these > records aren't changing, you are just trying to interpret > them in the context of the current day. That should be done > using a SELECT, not an UPDATE. > I like Jeff's idea of redefining the problem. If you need the data to contain dates in the last 30 days, you might want to consider storing an interval, then using a view that includes a calculation using CURRENT_DATE(). Regards, Paul Bort Systems Engineer TMW Systems, Inc. pbort@xxxxxxxxxxxxxx 216 831 6606 x2233 216 8313606 (fax) -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance