On May 7, 2007, at 8:53 AM, Jonas Henriksen wrote:
while if I add a GROUP BY data_logger the query uses a seq scan and a lot of time:explain analyze SELECT max(date_time) FROM data_values GROUP BYdata_logger_id;
What do you get if you run that with SET enable_seqscan = off; ? -- Jim Nasby jim@xxxxxxxxx EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)