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Thread: Normalization

  1. #1
    Join Date
    Sep 2006
    Posts
    20

    Question Dependency violated

    I've got this functional dependency, Department -> HOD(Head-Of-Department). But what do I do in case of change in the HOD of a department? Should I consider this dependency at all since for the same dept. in 2 tuples, diff. values of HOD would exist? Or is it better that the old HOD is overwritten by the new HOD? Same goes for class teacher. But this method reduces the usability of the software since we can't view which HOD a particular batch was under.
    If we don't consider the dependency, a very large no. of tuples would contain same value of HOD. I may be wrong. If you think I'm confused, do help me out.
    In OODBMS, we could create something like a linked list but still we cannot store which HOD was there for which batch? In RDBMS even this is not possible as far as I know. Or is it? If yes, how? Else, what do I do?
    Last edited by trss; 09-28-06 at 12:15.

  2. #2
    Join Date
    Jun 2003
    Location
    Ohio
    Posts
    12,592
    Huh?

    Table structure, please.
    If it's not practically useful, then it's practically useless.

    blindman
    www.chess.com: "sqlblindman"
    www.LobsterShot.blogspot.com

  3. #3
    Join Date
    Feb 2004
    Location
    One Flump in One Place
    Posts
    14,912
    Just an FYI Blindman. A little duplicate posting:
    http://www.dbforums.com/showthread.php?t=1608968

    The PM I refer to was mainly questioning what on earth I meant by "you have answered this yourself".
    Testimonial:
    pootle flump
    ur codings are working excelent.

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