Re: how to build a database from scratch

NENASHI, Tegiri a écrit :

> Sampo Syreeni <decoy_at_iki.fi> wrote in
> news:Pine.SOL.4.62.0612080913040.17498_at_kruuna.helsinki.fi:
>
> >
> > 2PL does make life easy, but you can't use it unless you know precisely
> > what data is going to be touched by a transaction when it begins.
>
> It is very strange what you say. Microsoft SQL Server utilizes 2PL and I
> think DB2 also. But one does not "know precisely what data is going to be
> touched". Then how it is possible that many of people use these databases
> ?
>
> --
> Tegi

SQL and DB2 have been implementing ORACLE Read Consistency since the SQL2005 and UDB 8.2. It essentially insures that in any context, the last COMMITTED version of the data is ALWAYS available independently from the transactional context that affects the tables. Received on Fri Dec 08 2006 - 15:05:35 CET