Re: insert vs select into performance

Tom Lane wrote:
> Michael Glaesemann <grzm(at)seespotcode(dot)net> writes:
>> It would be helpful if you included the actual queries you're using,
>> as there are a number of variables:
>
> Not to mention which PG version he's testing.

Its pg 8.1, for now, I'll be upgrading to a compile optimised 8.2 when I
do the real test on the real server.

(its on kubuntu 6.10 running on a Thinkpad T60 with dual core 1.5,GB RAM
and 100GB SATA, just in case anybody feels that is of any interrest.)

> Since (I think) 8.1,
> SELECT INTO knows that it can substitute one fsync for WAL-logging
> the individual row inserts, since if there's a crash the new table
> will disappear anyway.

I am not sure I understand you correctly here, are you saying that
SELECT INTO in 8.1 disables WAL logging and uses just a single fsync at
the end? in that case it means that I could disable WAL as well and
achieve the same performance, does it not?

regards

thomas