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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  •  孤独总比滥情好
    2020-11-29 01:46

    • consider a table={cid,sid,location}
    • candidate key: cidsid (uniquely identify the row)
    • prime attributes: cid and sid (attributes which are used in making of candidate key)
    • non-prime attribute: location(attribute other than candidate key)

    if candidate key determine non-prime attribute:

    i.e cidsid--->location (---->=determining) 
       then, it is fully functional dependent
    

    if proper subset of candidate key determining non-prime attribute:

     i.e sid--->location (proper subset are sid and cid)
             then it is term as partial dependency
    

    to remove partial dependency we divide the table accordingly .

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