Re: ORA 1562 Rollback segment problem

In article <3o34eb$3ds_at_athos.cc.bellcore.com>, parris_at_walleye.esp.bellcore.com (Parris Geiser) wrote:

> Hi,
> I have defined the table space for Rollback segments to a size
> of 4M. Our Product Test folks running a particularly large
 transaction,
> got ORA 1562. The transaction sometimes works and sometimes doesn't.
> In looking at the four segment sizes:
> RB1 532K
> RB2 665K
> RB3 2.5M
> RB4 400K
> Can anyone have a clue as to why the transaction sometimes fails?
> 4M seems like it should be enough space. Given that I'm in the
> situation, what is the best way now to get out?
>
> HP-UX with Oracle 7.0.16.4
>
> Thanks.
ORA-1562 is "failed to extend rollback segment".

Remember that transactions cannot span rollback segments, so each time the transaction in question runs, it is assigned to one of the four rollback segments. If the transaction uses all available space in that rollback segment and needs more, it will try to extend the rollback segment. If there is not enough space in the tablespace to extend the rollback segment, then you will get ORA-1562. If the rollback segment has already reached MAXEXTENTS, then you will get ORA-1562. There should be an additional error message to tell you more specifically why the rollback segment failed to extend.

Also, you should look at how much data this transaction is modifying - this will give you a better idea of how much rollback segment space it needs. You can explicitly assign a transaction to a particular rollback segment, which could help you avoid this problem in the future...

   -Kevin J Received on Tue May 02 1995 - 00:00:00 CEST