Partial Dependency(Databases)

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时光说笑
时光说笑 2020-11-29 01:19

I need closure on this. I fabricated a definition that partial dependency is when fields are indirectly dependent on the primary key or partially dependent but are also dep

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  •  隐瞒了意图╮
    2020-11-29 01:58

    Partial Dependency is one kind of functional dependency that occur when primary key must be candidate key and non prime attribute are depends on the subset/part of candidates key (more than one primary key).

    Try to understand partial dependency relate through example :

    Seller(Id, Product, Price)

    Candidate Key : Id, Product
    Non prime attribute : Price

    Price attribute only depends on only Product attribute which is a subset of candidate key, Not the whole candidate key(Id, Product) key . It is called partial dependency.

    So we can say that Product->Price is partial dependency.

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