Re: Performance testing of COPY (SELECT) TO

=?iso-8859-2?Q?B=F6sz=F6rm=E9nyi_Zolt=E1n?= <zboszor(at)dunaweb(dot)hu> writes:
> With PostgreSQL 8.1.4, I used this:

> begin;
> select ... into temp myquery1;
> copy myquery1 to stdout csv delimiter '|';
> rollback;

The performance of this would doubtless vary a lot with the temp_buffers
setting. Did you try different values?

It'd also be interesting to time the same way (with a temp table) in
devel. I don't remember whether we did any performance work on the
COPY CSV data path in this cycle, or whether that was all present in
8.1. In any case it'd be worth proving that the COPY SELECT patch isn't
degrading performance of the copy-a-relation case.

regards, tom lane