Re: Db2, Oracle, SQL Server

Mark A apparently said,on my timestamp of 7/02/2005 9:40 AM:

> Good database design for OLTP would suggest that if someone is in the middle
> of an update to a row, you should not see the old or current data until the
> work in progress work is committed or rolled back.

Completely wrong: if you can't see neither the old nor the current data, you can't update it at all. Unless you are into updating futures...

>
> The TPC-C benchmark has very strict and specific rules about data concurency
> and data consistancy. In an OLTP applciation (TPC-C) you don't want anyone
> reading data that is in the process of being updated by another application
> thread. You don't want anyone selling an item that is already promised to
> someone else (indicated by that someone else having a lock on that row while
> in the process of updating it). The TPC-C rules on this subject are very
> well thought out.

So what's all that "serialisation" rubbish for?

-- 
Cheers
Nuno Souto
in sunny Sydney, Australia
wizofoz2k_at_yahoo.com.au.nospam