Re: Just one more anecdote
Date: Tue, 26 Jul 2005 10:01:02 -0700
Message-ID: <22rce19csijp11c2haiaktuo6rmt1bqfv2_at_4ax.com>
On 25 Jul 2005 19:24:48 -0700, "dawn" <dawnwolthuis_at_gmail.com> wrote:
>I'm sure there are numerous factors playing into the fact that the
>system touted in this MS Word document
^^^^^^^^^^^^^^^^
I suggest a general one below.
>http://www.microsoft.com/resources/casestudies/ShowFile.asp?FileResourceID=1611
>
>has been discontinued and written off to the tune of $67 million in s/w
>development as seen at
>http://biz.yahoo.com/prnews/050721/clth018.html?.v=16
>
>This is yet another instance where a legacy system written with a PICK
>(in this case), MUMPS, IMS, or other pre-relational database product
>didn't successfully make the jump to a SQL-RDBMS.
Probably irrelevant.
>It is very likely that the conceptual data model and surely the
>subsequent logical data model from which the original system was
>developed would not play to the strengths of the SQL-DBMS. As much as
>we might want to think otherwise, even the design of a conceptual data
>model is influenced by the designer's knowledge of the target dbms. A
>redesign of the data model for a SQL-DBMS is likely to both bump
>features and increase complexity -- a harsh one-two punch.
Brook's Second System Effect
(<http://catb.org/~esr/jargon/html/S/second-system-effect.html>) seems
a likely culprit.
>My conjecture is that downgrading, I mean moving, from a graph data
>model to a relational data model and from a PICK dbms to the SQL-DBMS
>were significant factors in this project failure. I could be wrong, of
>course.
I think you are wrong or missing the biggest point, but not because of the PICK-SQL argument. Here is my take:
How many software projects fail? I think we agree that the percentage is all too high.
Original System was around for a while. It had made it over the
hump. It was a successful system. That made it one of the elite. It
may have been flawed, limited, whatever. No matter. It was a
success, enough of a success to be used for some time.
New System had not yet run the gantlet. It still had the
opportunity to fail. (With the Second System Effect, it had an even
bigger opportunity to fail.) It failed.
You are comparing a successful system to a failed system. Apples
and oranges.
I think that this hurdle would apply to any new system replacing an old one. I believe Machiavelli had something to say about new systems replacing old ones vs. a new system when there is no old system. In the first case, you have a conflict with those who like the old system that you do not have in the second case. (An example of this is the Pick vs. RM argument.)
Sincerely,
Gene Wirchenko Received on Tue Jul 26 2005 - 19:01:02 CEST