Unnormalized Relation
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Order no. Order date Item lines
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Item code Quantity Price/Unit
1 1/1/2001 100 1 100
200 2 50
Item code Quantity Price/Unit
2 2/1/2001 100 5 100
First Normal Form(1NF) [Flat File] - there is no composite attributes, and every attribute is single & describes 1 property.
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Order no. Order date Item code Quantity Price/Unit
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1 1/1/2001 100 1 100
1 1/1/2001 200 2 50
2 2/1/2001 100 5 100
2NF:if it is in 1NF and non-key attributes are functionally dependant on the key attribute(s).
Orders: Order Details:
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Order no. Order date
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Order Details:
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Order no. Item code Quantity
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Prices:
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Item code Price/Unit
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3NF:where all attributes in a relation are not functionally dependent only on the key. If 2 non-key attributes
are functionally dependent.
2NF:
Stud_id Name Department Year Hostel name
1 A Physics 1 xyz
2 B Math 3 abc
Converting 2NF: to 3NF:
Stud_id Name Department Year
1 A Physics 1
2 B Math 3
Year Hostel name
1 xyz
2 def
3 abc
Reference book:Analysis & Design of Information Systems By:V.RAJARAMAN
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