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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  •  佛祖请我去吃肉
    2020-11-29 01:41

    Partial Functional Dependency occurs only in relation with composite keys. Partial functional dependency occurs when one or more non key attribute are depending on a part of the primary key.

    Example:

    Table: Stud_id, Course_id, Stud_name, Course_Name

    Where: Primary Key = Stud_id + Course_id

    Then: To determine name of student we use only Stud_id, which is part of primary key.

    {Stud_id} -> {Stud_Name}

    Hence,Stud_name is partially dependent on Stud_id. This is called partial dependency.

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