On 11 October 2010 18:48, Tom Lane <[email protected]> wrote: > Dean Rasheed <[email protected]> writes: >> On 11 October 2010 18:37, Tom Lane <[email protected]> wrote: >>> Sure it would: an estimate of 30K would keep the planner from using >>> hash aggregation. > >> Not if work_mem was 10MB. > > And? If the memory requirement actually fits, you're in good shape. >
Yeah but the actual memory requirement, if it uses a hash aggregate, is over 1GB, and could easily be much higher. It's also hard to kill, because it eats up that memory so quickly. Regards, Dean -- Sent via pgsql-hackers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
