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To summarize, we're going to do relational design by decomposition.
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We're going to start by specifying mega
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relations that contain all the
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information that we want to capture,
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as well as specifying properties of
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the data usually reflecting the real world in some fashion.
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The system can automatically decompose
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the mega-relations into smaller relations
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based on the properties we specify,
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and guarantee that the final
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set of relations have certain
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good properties captured in a normal form.
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They will have no anomalies, and they'll be guaranteed not to lose information.
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We'll start by specifying properties as
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functional dependencies and from
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there the system will guarantee Boyce-Codd
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Normal Form and then we'll
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add to that properties specified as
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multi-value dependencies, and from
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there the system will guarantee fourth
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normal form, which is even
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stronger than Boyce-Codd Normal Form and
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is generally thought to be good relational design.