ERwin vs Designer/2000

Robert Miller wrote:
>
> David Ng wrote:
> >
> > Jim Russell wrote:
> > >
> > > Robert Miller wrote:
> > > > From what I've seen of Erwin's Oracle schema generator, I was not
> > > > impressed. Perhaps it was due to cockpit trouble on the part of the [Quoted]
> > > > designer. (sorry, modeler...)
> > > >
> > > > Instead of generating declarative referential integrity constraints when
> > > > foreign keys are specified, the thing create a trigger for every foreign
> > > > key.
> > >
> > > I've seen that same output from ER/Win, and I wonder if I'm just failing
> > > to understand it -- the thing generated bunches of triggers rather than
> > > defining constraints. I also played once with S/Designer and was
> > > underwhelmed -- When I tried to reverse engineer a DB I had set up by
> > > hand, the damn thing ignored existing trigger definitions, and replaced
> > > the constraints defined with a slew of triggers. Can someone explain
> > > the reasoning behind that??
> > > (With ER/Win, my target db's were SQL Anywhere and Oracle 7; in
> > > S/Designer I was using just Oracle 7.)
> > > --
> > > /Jim Russell (temp alt: russelj0_at_hoffman.army.mil)
> > > Entity: an object with no class that doesn't know how to behave.
> >
> > I consider that is one of major strength of ERWin. ERwin can generate
> > same triggers for different target databases. Further, it can generate
> > some triggers that is not easy to program in the target database. For
> > example, to ensure casecade update between master and detail table in
> > Oracle database, it take a quite a lot of effort to do so. ERWin can
> > generate trigger for that on the fly and save you a lot of effort.
> >
> > David Ng
>
> David,
>
> First, you do not need triggers for on delete cascade. Declaritive
> referential integrity specifies this when the table is created. The
> statement is ON DELETE CASCADE. No trigger required.
>
> This is not a strength but a pox. Declaritive referential integrity is
> the industry proven way to go. I'm probably wrong, but I always thought
> it was part of ANSI92 entry level. (I hope Joe Celko isn't reading
> this). TRIGGERS ARE SLOW (at least they were at the time I saw
> product displayed). In Oracle, they started life as interpretive. In
> 7.3 they are now compiled. Also databases have a limit (usually or
> initially) that can be applied to any one table. I suspect this
> technique is there for one reason. This "feature" is the least common
> demoninator a CASE tool generator can use and CLAIM it supports another
> vendors RDBMS.
>
> I was appalled, and I would not allow purporting to build a database
> like this for me or my customer. This same modeler, might then claim
> "Oracle is Slow" when the application is placed into service.

Guys,

        Not sure that I want ot get into this, but I've used ERwin on Solaris and Des2K on NT for some time, and I guess I come away with mixed emotions. Your responses seem to focus on triggers, but both packages contain more than that.

        For my bucks, each has its strengths, though ERwin is like Des2K "Lite" (maybe VERY lite). ERwin is faster to use to go from an ERD to a generated schema, and the point and click referential integrity isn't that bad. You can do limited reverse engineering in ERwin as long as you know that you have to tweak the results, and also tweak the results during initial schema generation, i.e., look at the SQL and see if it's what you wanted, specifically. I can make changes to existing schema in ERwin very quickly. The package is OK for what it does, and it handles the major engines.

        Des2K is many programs glued together to provide a fairly complete package, but it's not trivial to learn (or even use, cause you rarely use all the pieces for each developmental effort). Des2K gives you a lot more choices: even if you set the defaults, you'll be changign them for a new development result. It has a ERD "chain" and a process modeller (hierarchical modeller) chain as well as some fairly good code generators. The more time spent learning it, the better the results.

        In my mind, they're too dissimilar to really compare. ERwin was made to go fromt he ERD to the schema generation with a couple of bells and half a whistle, while DES2K was designed as an ERD generator, process modeller, code generator, PLUS giving you a vanilla Forms and Report generator.

                        Tom Rudy Received on Mon Apr 14 1997 - 00:00:00 CEST