On Sun, 2007-10-28 at 13:19 -0700, CK Tan wrote: > Hi, this query on TPCH 1G data gets about 5% improvement.
> select count (*) from (select l_orderkey, l_partkey, l_comment, > count(l_tax) from lineitem group by 1, 2, 3) tmpt; > On Oct 28, 2007, at 1:17 PM, Luke Lonergan wrote: > > > We just applied this and saw a 5 percent speedup on a hash > > aggregation query with four colums in a 'group by' clause run > > against a single TPC-H table (lineitem). > > > > CK - can you post the query? Is this on Postgres or Greenplum? That looks like quite a wide set of columns. Sounds good though. Can we get any more measurements in? -- Simon Riggs 2ndQuadrant http://www.2ndQuadrant.com ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
