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Chapter 1. Entities > Existence

Existence

In a record processing system, records are created and destroyed, and we can decide with some certainty whether or not a given record exists at any moment in time. But what can we say about the existence of whatever entities may be represented by such a record?

HOW REAL?

It is often said that a data model models some portion of the real world. I've said so in this book.


  

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