Re: Oracle transactions and DDL statements.

Vladimir M. Zakharychev wrote:
> "Vladimir M. Zakharychev" <bob--nospam--_at_dynamicpsp.com> wrote in message
> news:e3shfa$23hn$1_at_hypnos.nordnet.ru...
> >
> > Pardon my ignorance, but is it really possible to rollback a
> > CREATE TABLE in MS SQL Server??? I am not sure
> > how DDL affects your current transaction in MSSQL,
> > maybe it runs DDL autonomously, but afaik you can't
> > rollback DDL in MSSQL, too.
> >
> Actually it looks like I'm wrong and it's doable within
> BEGIN TRAN..END TRAN block.Hi Vladimir

Thank you for testing this for me. It is as I expected, but saves me from verifying.

> Amazing. I wonder
> how they manage to rollback an ALTER TABLE of
> a big existing table....

I do not really see the problem. They must be able to do a roll back if a failure happens during the statement, so what particular problem do you expect the "full monty" to bring?

While you could perhaps improve performance if you know that ALTER TABLE will be the only statement that should be processed, you could do that optimisation by deferring the execution of the statement until you see the COMMIT. If the subsequent statement is not a COMMIT (well - you could optimise this part), you simply perform the ALTER TABLE the slow and more easily roll-backable way.

Kind regards
Peter
>
> --
> Vladimir M. Zakharychev
> N-Networks, makers of Dynamic PSP(tm)
> http://www.dynamicpsp.com
Received on Wed May 10 2006 - 07:03:17 CDT