Hi, Phillipe! You're facing the same problem I had with a client about two months ago. May I suggest going to MetaLink and look up the following docs: 40689.1 -- very good overview of the 01555 problem. Possible causes and suggested solutions. 252686.1 -- very specific (and very NEW) doc. You didn't mention O/S or Oracle Version. This brief article deals with Solaris and 9.2.0.<3 and 4>. It sites BUG #3060261. My experience was that regardless of how high you set the undo retention time (we stopped experimenting at 18 hours, though the query ran in under two before this problem reared its ugly head), the 01555 wouldn't go away. When I researched the bug noted above, it seemed applicable to most O/S, and described a symptom that we were experiencing dead on accurately. Anyway, I'd like to say that the patch worked, but I really don't know. The company ran out of money to renew my contract before I had the chance to install and test it. (So now I put out fires for another company!) I wish you the best of luck in solving this problem. HTH Joe Cooper Senior Oracle DBA Sheshunoff Information Services (a Thomson Media company) "NGUYEN Philippe (Cetelem)" <philippe.nguyen@xxxxxxxxxx> wrote: Justin, Richard thank for your answer, I will increase the undo retention time and let you know... --------------------------------- Do you Yahoo!? Yahoo! Search - Find what you?re looking for faster.