Re: "Transactions are bad, real bad" - discuss
Date: Wed, 30 Apr 2003 10:03:11 +0200
Message-ID: <3eaf833f$0$42612$edfadb0f_at_dread11.news.tele.dk>
"Paul Vernon" <paul.vernon_at_ukk.ibmm.comm> skrev i en meddelelse
news:b8ljgd$383i$3_at_gazette.almaden.ibm.com...
> "Jonathan Leffler" <jleffler_at_earthlink.net> wrote in message
> news:3EAE16E6.2070803_at_earthlink.net...
> > In an article under the thread "Do Data Models Need to [be] built on a
> > Mathematical Concept?", Paul Vernon commented:
> > >>transactions
> > >
> > > Dead wrong. Transactions are bad, real bad. In short they are not
> > > compatible with the 'arrow of time'. They let you freeze time and
> > > that is not a good model of reality. Start a new thread if you want
> > > to discuss the details, I've a draft paper on the subject and a
> > > could do with some intelligent challenges to sharpen up my
> > > argument.
> >
> > Herewith, a new thread - unless someone else got there first.
>
> Thanks for starting the thread Jonathan (and Marshall also).
>
[snip]
>
> Imagine the business rule:
> 'all bids must be made within 1 hour of the auction opening'
>
> With transactions, this rule is compromised. A user could simply open a
> transaction before the end of the 1 hour deadline, make a bid at then only
> decide to commit (or rollback) the bid at his leisure after the end of the
> deadline.
>
> With transactions you cannot get 'strong application independence' - the
> database cannot stand alone and be used by just any old application or
> interfere.
> >
> The argument above is probably the most cutting against transactions, but
I
> have many others... I think I'll leave them to later...
Hi Paul
I remember this being brought up before and will remind you that your model
does not prevent malicious users from getting the effect mentioned above. As
a simple example, the malicious user could issue the statement
MAKE_A_BID,
SIT_IDLE_FOR_48_HOURS;
SIT_IDLE_FOR_48_HOURS would not necessarily have to be an idle loop, of
course. It could just as well be some other time-consuming DBMS-action such
Kind regards
Peter
Received on Wed Apr 30 2003 - 10:03:11 CEST