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Old March 25th, 2008, 10:01 PM
dparsons dparsons is offline
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Yes I would say tblSongs is in 3NF since both SongTitle and ArtistID don't rely on one another to be related to SongID.

Now if you were to add a forth column in there, say albumnTitle, this would break 3NF because albumnTitle would become dependant on SongID but only because it is related to an artist which is then in turn related to a SongID.

First I would say no, your customer table is not in 3NF because the value of City relies on who the person is which in turn relates the value to CustID so your assumption is correct, you would need to break out a table for city. I can't speak for an academic but normally what I do is break a "Person" table out into at least 3 tables:

Personal Information (Name, SSN, DOB)
AddressInformation(Shipping Information & Billing Information) <--Each address would be 1 row within the table
ContactInformation(PhoneNumbers, Email, etc)

Also I will normally have ancilliary lookup tables for States, Gender, etc.

Make sense?

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