Re: Troubleshooting ORA-01555 while using AUM

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:<c21onv$bdq$1_at_hercules.btinternet.com>... ---snip---
> Are you using LOBs, and is it possible that the failures
> are due to LOB chunk overwrites. I haven't checked
> whether the LOB error is reported at the top level as
> 1555, or as the underlying 22924 - this could be a
> cause of confusion. I also don't know if a LOB snapshot
> too old would appear in v$undostat (I doubt it, as it's
> not caused by destruction of undo).
> --
> Regards
>
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk

---snip---

I recently ran across LOB overwrite causing consistent 1555 errors. This is what I saw:
* LOB overwrites are reported at the top level as 1555 and 22924. An example   of the actual message being:
  ORA-01555: snapshot too old: rollback segment number with name "" too small   ORA-22924: snapshot too old

  wherein the rollback segment name is not listed .. since there is none to   report.
* The v$undostat also does not report it in the ssolderrcnt column (as you   guessed it). The count remains 0 after this specific error/case.

Anurag Received on Tue Mar 02 2004 - 15:28:51 CST