Re: Is ORM still live ???

> what i mean is:
> 1)
> There are a lot of books on UML and ER but only one on ORM.
> 2)
> There are a lot of tools for building UML and ER models but only two
> for ORM
> 3)
> ORM is "sponsored by Microsoft" and a lot of people don't like MS

I'm not sure I'd let popularity decide how I engineer systems. Tools are largely irrelevant in my opinion. Good engineers can make good designs and express them by chiseling them on rocks or interpretive dance. It is how you think about the problem and how you communicate with the business users that matters.

I've argued for a long time that to be successful at ER modeling, you really have to think in ORM even if you draw rectangles later. The whole is-it-an-attribute-or-an-entity decision that happens essentially looks at whether or not the role between the two things is functional or not. In ORM, those two things are objects and their relationship determines if it becomes an entity or attribute. Good ER modelers just think about that before they commit pen to paper; in ORM it is part of the process.

I'm not sure about dates, but I think most ORM research predates the existence of Microsoft so number 3 is specious. At the risk of being cynical and with tongue planted in cheek, the fact that a lot of people do one particular thing is usually a good reason to do the opposite.

Ultimately, tools are picked for a myriad of reasons that seldom have anything to do with superiority of one method over another. Use what works or what you have to use because otherwise you end up in hours of meetings with the standards groups at your company. You know the ones, they get really, really mad that you because abbreviated "description" as "desc" even though the standard -- coined when the database platform of choice only allowed 16-character names -- is "dsc". They also tend to have heart palpitations that you prefer to use a tool other than ER Win or that your crows feet don't have the right line thickness.

Just think about it the right way. Why not learn all the methods? It will only make you a better designer.

Hope that helps,
Scot.

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Orthogonal Software
www.orthogonalsoftware.com

ORM Blog: www.objectrolemodeling.com Received on Fri Nov 21 2003 - 18:47:57 CET