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Old November 24th, 2011, 12:00 PM
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Rod Stephens Rod Stephens is offline
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Hi frdata,

The book focuses on design rather than implementation so I didn't build all of the example databases in a particular database. Partly I didn't want to assume that you use a specific database because the details about how you do things like create foreign key constraints is different in different database systems. Chapters 15 and 16 were the exceptions.

For this particular example, I would probably also continue to 3NF and implement the structure shown in Figure 14-5.

As to your question about Employees/Person being many-to-one, I think that must have been a typo. Person is a detail table that provides extra detail about someone. I can't think of a reason why one Person might correspond to multiple Employees. (Unless an employee is schizophrenic.) I suspect that error got into the model in Chapter 13 and then just got carried along into the later versions.

We are looking at the possibility of making a new edition to this book. I'll see what the editor thinks about providing database implementations, although I think we still want to keep the book as database-neutral as possible.

Thanks for the ideas and for pointing out the error in the design.
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Rod Stephens, Microsoft MVP

Essential Algorithms: A Practical Approach to Computer Algorithms

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