So What’s the Problem?

Unit Company Product

Unit Company

Unit Product

Galaga99 UW Galaga99 databases

NullValue UW NullValue databases

No problem so far. All local FD’s are satisfied.

Let’s put all the data back into a single table again:

Galaga99 UW databases

NullValue UW databases

Violates the dependency: company, product -> unit!

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