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u |
Why
Be Normal?
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Easy
applications from well-designed data,
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poorly
designed data makes for tough apps
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u |
Primary Key (PK) uniquely defines record (1st)
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All parts of PK required to identify record (2nd)
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No other fields needed for uniqueness (3rd
)
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When
a record wants to refer to another, it
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stores
the PK of that record. That field is a
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foreign
key (FK)
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