Re: PostgreSQL as a local in-memory cache

Dave Page <dpage@pgadmin.org> writes:
> On Wed, Jun 23, 2010 at 9:25 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>> I don't think we need a system-wide setting for that. �I believe that
>> the unlogged tables I'm working on will handle that case.

> Aren't they going to be truncated at startup? If the entire system is
> running without WAL, we would only need to do that in case of an
> unclean shutdown wouldn't we?

The problem with a system-wide no-WAL setting is it means you can't
trust the system catalogs after a crash.  Which means you are forced to
use initdb to recover from any crash, in return for not a lot of savings
(for typical usages where there's not really much churn in the
catalogs).  I tend to agree with Robert that a way to not log content
updates for individual user tables is likely to be much more useful in
practice.

            regards, tom lane