On Tue, 2006-02-14 at 10:32, martial.bizel@xxxxxxx wrote: > command explain analyze crash with the "out of memory" error > > I precise that I've tried a lot of values from parameters shared_buffer and > sort_mem > > now, in config file, values are : > sort_mem=32768 > and shared_buffer=30000 OK, on the command line, try increasing the sort_mem until hash_agg can work. With a 4 gig machine, you should be able to go as high as needed here, I'd think. Try as high as 500000 or so or more. Then when explain analyze works, compare the actual versus estimated number of rows.