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databasedatabase-designnormalization3nfthird-normal-form

Are my DB tables normalised to 3NF?

I need to make sure my schema is in 3NF, but am not too sure about my "StudentHomework Table" can someone help?

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Solution

  • The main concern I have with your approach is the lack of relation between Teacher and Subject.

    The way I see it, a HomeworkTask should have a SubjectId, and the Subject should be taught by a Teacher.

    So, I would do this. A new Table, Subject:

    Table Subject:
Id (PK)
TeacherId (FK)
Name
Description
... any other fields necessary

    Then, refactor HomeworkTask:

    Table HomeworkTask:
Id (PK)
SubjectId (FK)
HomeworkTitle
SetDate
DueDate

    Apart from this, you have clear Primary keys, all non prime attributes depend on the PKs and nothing but the PKs, so you should be home free for the 3rd normalization form.

    Hope this helps. Cheers!