Re: reducing bloat in pg_statistic

Robert Treat <xzilla(at)users(dot)sourceforge(dot)net> writes:
> I'm looking at a postgresql 7.3 database that has gotten rather bloated
> in pg_statistic:
> I am trying to figure out a way to shrink this down to something more
> reasonable, with the caveat of not restarting the database server.

You haven't got too many options in 7.3, but it might work reasonably
well to do
delete from pg_statistic;
vacuum full pg_statistic;
re-analyze to repopulate
vacuum full with no records should take well under a minute. It won't
shrink the index, but it'll fix the table bloat which seems the worst
part.

The main gotcha here is that any queries started before you can finish
the re-analyze will not have the benefit of statistics; in the worst
case they might choose bad enough plans that you'll wish you had not
done it.

regards, tom lane