Thank you! Gene Sais, DBIA COCC Automation Services Department 205 North Dixie Highway, Room 2.2209 West Palm Beach, FL 33401 P: 561.355.3467 F: 561.355.2600 C: 561.662.2018 [#3] E: Gsais@xxxxxxxxxxxxxxxxxxx >>> jonathan@xxxxxxxxxxxxxxxxxx 06/19/04 3:44 AM >>> A tablespace can only be made read-only after all active transactions that started BEFORE the read-only call have committed. Consequently, no transactions or query that starts after the tablespace is read-only needs to do anything about read-consistency, delayed block cleanout, or commit-time checking. HOWEVER - queries that started before the tablespace went readonly (or sessesions that set transaction read only) could still be running after the tablespace went read-only, and these need could to apply undo. This is why "after a sufficient period of time" the problem stops happening. The problem can't happen in a read-only database because the only way to make a database read-only is to stop and restart it (I think) so every query has to have started after the database (all tablespaces) became read-only. Regards Jonathan Lewis http://www.jlcomp.demon.co.uk http://www.jlcomp.demon.co.uk/faq/ind_faq.html The Co-operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/seminar.html Optimising Oracle Seminar - schedule updated May 1st ----- Original Message ----- From: "Gene Sais" <Gsais@xxxxxxxxxxxxxxxxxxx> To: <psinger1@xxxxxxxx>; <oracle-l@xxxxxxxxxxxxx> Sent: Thursday, June 17, 2004 6:14 PM Subject: [.] RE: Tbs READ ONLY and Snapshot too old : Would this apply to a read-only database as well? I haven't seen it in : my read-only database, has anyone discovered this error? : : >>> psinger1@xxxxxxxx 6/17/2004 12:34:45 PM >>> : Actually, you are both right. : : Delayed Block Cleanout can cause an ORA-1555, even in a read only : tablespace. : : However, if the tablespace has been read only "for a long enough period : of time", : every query against it will realize that all updates to objects in that : tablespace have : been committed, and will never try to reconstruct the table. ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------