Re: How does ORACLE manages the rollback segments ??

In article <4elhnv$hnf_at_news2.aimnet.com>, Tony Damon <bfntd_at_aimnet.com> writes
>Pierre ROUSSIN (roussin_at_micronet.fr) wrote:
>:
>:
>: We want to know how the rollback segments are dispatched to
>: the user processes. And why if it's the case; two users get
>: to be on the same RBS.
>:
>:
>: Thanks for an answer.
>:
>
>I believe you can specify the order in the parameter file:
>
>rollback_segments = (r01, r03, r02, r04)
>
>Transactions will then be assigned in order to r01, r03, r02, r04
>then back around to r01. Multiple transactions can be assigned to
>a given rollback segment, but they will be in a different extent.
>
>If you're having problems with multiple transactions in the same RBS,
>perhaps you could create an RBS with 1 big extent?
>
>HTH,
>Tony Damon
>

Rollback segments are assigned to a transaction on a "round robin" basis. The only exception to this is if you use the statement:

        SET TRANSACTION USE ROLLBACK SEGMENT seg_name;

This statement must be submitted prior to any DML statements are issued.

By the way you must have at least 2 extents to a rollback segment.

Regards  

Clive Bostock Received on Tue Jan 30 1996 - 00:00:00 CET