We went from 10.2.0.3 CPU 12 (I think it was) to 10.2.0.4 CPU 24 and discovered a bug I didn't know existed. If you're using ANSI SQL in 10.2.0.3 prior to 10.2.0.4 CPU 2, ORA-00918 Ambiguous Column may not get raised. After patching, you'll have code that starts failing if you failed to properly alias duplicate columns. Here's the bug: Bug 5368296 - ANSI join SQL may not report ORA-918 for ambiguous column [ID 5368296.8] Just wanted to pass it along. Chris Taylor Sr. Oracle DBA Ingram Barge Company Nashville, TN 37205 Office: 615-517-3355 Cell: 615-354-4799 Email: chris.taylor@xxxxxxxxxxxxxxx<mailto:chris.taylor@xxxxxxxxxxxxxxx> CONFIDENTIALITY NOTICE: This e-mail and any attachments are confidential and may also be privileged. If you are not the named recipient, please notify the sender immediately and delete the contents of this message without disclosing the contents to anyone, using them for any purpose, or storing or copying the information on any medium.