On Sat, 2007-01-06 at 21:32 -0500, Tom Lane wrote: > Robert Treat <[EMAIL PROTECTED]> writes: > > On Saturday 06 January 2007 16:36, Simon Riggs wrote: > > <snip> > >> BEGIN; > >> CREATE TABLE foo... > >> INSERT INTO foo --uses WAL > >> COPY foo.. --no WAL > >> INSERT INTO foo --uses WAL > >> COPY foo.. --no WAL > >> INSERT INTO foo --uses WAL > >> COPY foo... --no WAL > >> COMMIT; > > > Is there some technical reason that the INSERT statements need to use WAL > > in > > these scenarios? > > First, there's enough other overhead to an INSERT that you'd not save > much percentagewise. Second, not using WAL doesn't come for free: the > cost is having to fsync the whole table afterwards. So it really only > makes sense for commands that one can expect are writing pretty much > all of the table. I could easily see it being a net loss for individual > INSERTs.
Agreed. We agreed that before, on the original design thread. -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
