Re: Strange Performance Behavior on INSERT INTO SELECT statement...

Andrew:

Do you think that the rollback could cause such a large performance difference when the view in question returns only one row? ( I'm not sure I mentioned that or not)

Dave

Andrew Babb wrote:
>
> Dave,
>
> These are thoughts and not backed up with solid proven experience.
>
> NOLOGGING simply means that the database inserts are not recorded in the
> Redo Logs and therefore the operation is not recoverable in the event that
> you need to perform Media Recovery. I believe that the dictionary
> modifications are still logged though.
>
> ROLLBACK logging is required with a simple insert as select because if the
> user fails or gets logged off, the PMON (or SMON) is still going to tidy up
> the connection and abort the transaction. Maybe as suggested, the amout of
> Rollback generated is reduced when using CREATE as SELECT.
>
> Rgds
Received on Thu Apr 29 1999 - 16:37:29 CDT