explain extended select * from srcpart a join srcpart b where a.ds = '2008-04-08' and a.hr = '11' and b.ds = '2008-04-08' and b.hr = '14' limit 5; select * from srcpart a join srcpart b where a.ds = '2008-04-08' and a.hr = '11' and b.ds = '2008-04-08' and b.hr = '14' limit 5;