Re: Fastest DB restore options

----- Original Message ----
From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>

ogjunk-pgjedan(at)yahoo(dot)com writes:
> I normally dump with these options:
> -d MyDB --clean --inserts --column-inserts --format=P
> But the last time I tried that, the restore took foreeeeeeeeeeeeeever.

--inserts is pretty expensive.

OG: right. I won't use -d then.

> So I'm looking for the fastest way to import data from the old DB to the new one. Judging from pg_dump man page the following should be the fastest dump & restore:

> -d MyDB --format=c --ignore-version

Don't use --ignore-version; it's a good way to shoot yourself in the foot.

OG: even when upgrading (8.0.3 -> 8.2.3)? I'll dump with pg_dump from 8.0.3 and them import with pg_restore from the newly installed 8.2.3. Wouldn't I *have to* use --ignore-version for that to work?

pg_dump's default behavior is about as good as you can get; there are no
optional switches that will make it faster. What you *can* do is make
sure that the receiving system is properly configured before you start
the restore --- increase maintenance_work_mem and checkpoint_segments
in particular. See this page, especially the last section:
http://www.postgresql.org/docs/8.2/static/populate.html

OG: Thanks for the pointer!

Otis