On Fri, Mar 24, 2006 at 11:25:35AM -0700, [EMAIL PROTECTED] wrote: > test-# $$ select not exists > test$# (select * from test_dates t1 > test$# where 1 < ( select count(*) from test_dates t2 > test$# where (t1.from_date, t1.to_date) overlaps > test$# (t2.from_date, t2.to_date)) )$$;
<pet-peeve> If you only want to know if something exists, do NOT use count! > test$# (select * from test_dates t1 > test$# where EXISTS ( select * from test_dates t2 > test$# where (t1.from_date, t1.to_date) overlaps > test$# (t2.from_date, t2.to_date)) )$$; On a small dataset you may not notice much difference, but you'll certainly see it on a large dataset. </pet-peeve> -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
