Reply To: Associative Classes and Referential Attributes

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#5438
Lee Riemenschneider
Participant

After perusing the aforementioned forums, the miUML discussions, and my own metamodel musings, the only conclusion is that there is no concensus. The xtUML pundentry is split about 50/50 on this topic, so I’ll just have to address John’s question and explain myself.

I have always found a usefulness to addressing referential attributes and their placement when doing analysis of a problem space. I mused in the Yahoo! forum that maturity in modeling might obviate the usefulness of this, but I can’t say I found this to be true. The same goes for contrived identifiers. I can clearly state that I will always put them in my models.

Given the above, I have a real hard time assigning an attribute to a class that is only an attribute sometimes. This would be an incomplete model in my mind. I could probably back this up with some words of wisdom from C.J. Date ala. relational, but … This is the crux of my no NULLs rule; it applies only to me, and I’m not proposing otherwise.

Maybe once I finish my metamodel analysis, I’ll have a stronger argument, but for right now, it’s just a preference.