Re: Is using OPTIMAL in RBS ORA-1555 prone?

From: Svend Jensen <Master_at_OracleCare.Com>
Date: Wed, 20 Feb 2002 18:22:03 +0100
Message-ID: <3C73DB3B.6010303@OracleCare.Com>

Tianhua Wu wrote:

> , some consistent lookups in a
>

>>rollback segment was just deallocated by optimal, just before you got 
>>there - the database engine has no problems finding the data, they are 
>>there, well preserved in a deallocated rollback segment.
>>

>
> Are you sure about that? That is contradict to my experience. I
> understand that the info is still there. However Oracle will use a
> block that does not belong to the segment anymore? I definitely need
> proof for this claim. If this is true, you should have no trouble get
> data back right after you truncate a table as long as nobody else use
> the space (Oracle can just use similar mechanism)! Of course you can
> say flash back query for 9i, but that is different story.
> Unfortunately I do not have a testing database now.
>

Truncate doesn't generate rollback, and yes the data is still there on the file on disk, but you can't get to it with std. oracle ways. And i'm not sure all versions on all platform behave alike, so a test is needed with your version on your platform. /svend Received on Wed Feb 20 2002 - 11:22:03 CST