Re: Very slow updates when using IN syntax subselect

Peter Eisentraut <peter_e@gmx.net> writes:
> Bryce Nesbitt wrote:
>> They occur in fine time.  That's good, thanks.  But jeeze, can't
>> postgres figure this out for itself?

> I'm sure you wouldn't appreciate it if PostgreSQL did a full table scan 
> before each query to figure out the total size of the involved tables.

It's also less than polite to complain about the behavior of
two-year-old releases, without making any effort to ascertain
whether more-current versions are smarter.
        regards, tom lane