David Fetter <david@fetter.org> writes:
> On Sun, Jul 01, 2007 at 03:55:11PM -0400, Alvaro Herrera wrote:
>> So mount a ramdisk and initdb in there.

> You could also put a tablespace on a ramdisk and create the table
> there.

The fresh-initdb approach is more likely to work without any strange
corner cases. If you try a setup where the system catalogs are on
persistent storage but you have a tablespace on ramdisk, then after
restart you'll have pg_class entries referencing files that don't exist
anymore, which I believe will provoke errors.

Also, I doubt the OP wants his WAL on real storage either ...

regards, tom lane

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