Jonathan has answered your main question however I have one question to you: I'm just wondering what's the reason for SELECT distinct .... WHERE rownum = 1 Are you planning to find duplicates in one row? ;) I don't know whether Oracle is smart enough actually not to make sort/hash unique each time when it finds 1 row (probably a question for Jonathan? ;), but at least to me as a developer it would be a misleading "distinct". Gints Plivna http://www.gplivna.eu -- //www.freelists.org/webpage/oracle-l