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ERD and normalization 3FD

is this relationship is true in 3FD normalization? and what can i do with the (phone number), it is Determines all rows? please any one help me to convert this relationship to 3FD and in Correct relationship.

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Solution

  • Phone number will not be a good determinant for PATIENTS if this is a real world example. Some patients will share phone numbers, some patients will have multiple phone numbers, and some patients (young children, homeless people) might not have a phone number at all.

    Your model is nominally in 3NF already. Every non-key attribute of each of the tables is fully functionally dependent on every candidate key (and nothing else). This is trivial in your case because you've declared surrogate keys for your primary key and you haven't declared unique constraints for any alternative candidate keys.