"Matthew Nuzum" <matt(dot)followers(at)gmail(dot)com> writes: > Here is the query (BTW, there will be a corresponding "max" version of this > query as well): > INSERT INTO usage_sessions_min (accountid,atime,sessionid) > select accountid, min(atime) as atime, sessionid from usage_access > group by accountid,sessionid;
How many rows in usage_access? How many groups do you expect? (Approximate answers are fine.) What PG version is this, and what's your sort_mem setting?