I probably shouldn't ask, but how does one session know that another session has uncommitted values about to be committed that would conflict with what itself? But aside from that, I wish to report back to the developers that are asking about this that --... essentially it is an application issue... and provide some suggestions such as the order of tables and/or rows... but more specifically in this case, from what I am reading, it is counter productive to report back that the trace file is incorrect... Does it imply that this could be an anomaly and just wait and see if it is a reoccurring issue? This is probably new code; the errors are in a UAT DB. Joel Patterson Database Administrator 904 928-2790 -- Joel Patterson Sr. Database Administrator | Enterprise Integration Phone: 904-928-2790 | Fax: 904-733-4916 http://www.entint.com/ http://www.entint.com/ http://www.facebook.com/pages/Enterprise-Integration/212351215444231 http://twitter.com/#!/entint http://www.linkedin.com/company/18276?trk=tyah http://www.youtube.com/user/ValueofIT This message (and any associated files) is intended only for the use of the addressee and may contain information that is confidential, subject to copyright or constitutes a trade secret. If you are not the intended recipient, you are hereby notified that any dissemination, copying or distribution of this message, or files associated with this message, is strictly prohibited. If you have received this message in error, please notify us immediately by replying to the message and deleting it from your computer. Messages sent to and from us may be monitored. Any views or opinions presented are solely those of the author and do not necessarily represent those of the company. [v.1.1] From: Jonathan Lewis [mailto:jonathan@xxxxxxxxxxxxxxxxxx] Sent: Wednesday, March 20, 2013 11:09 AM To: Patterson, Joel Cc: oracle-l@xxxxxxxxxxxxx Subject: Re: Deadlock inserting into same rowid (different block) The deadlock pattern is indicative of collisions on a unique constraint. They're both trying to insert primary / unique key values already inserted but not yet committed by the other session. Given that the slot numbers are both zero, it's likely that they're being reported incorrectly - Oracle doesn't clean out the wait information for every single wait, so these could be the file and block (with zero row) for early buffer busy waits, or read by other session or some such. Regards Jonathan Lewis http://jonathanlewis.wordpress.com/all-postings Author: Oracle Core (Apress 2011) http://www.apress.com/9781430239543 ----- Original Message ----- From: "Patterson, Joel" <jpatterson@xxxxxxxxxx> | | Deadlock graph: | ---------Blocker(s)-------- ---------Waiter(s)--------- | Resource Name process session holds waits process session holds waits | TX-001a0015-00014787 34 90 X 32 3 S | TX-00190008-0000601b 32 3 X 34 90 S | | session 90: DID 0001-0022-00000327 session 3: DID 0001-0020-000009E9 | session 3: DID 0001-0020-000009E9 session 90: DID 0001-0022-00000327 | | Rows waited on: | Session 90: obj - rowid = 00030CE5 - AAAwzlAAGAABDiuAAA (dictionary | objn - 199909, file - 6, block - 276654, slot - 0) Session 3: obj - | rowid = 00030CE5 - AAAwzlAAGAABp8gAAA (dictionary objn - 199909, file | - 6, block - 433952, slot - 0) | | | -- //www.freelists.org/webpage/oracle-l