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First 3 Rules of Data Normalization for Newbies - Part 2
In yesterday's blog, I discussed 1NF. Today, as promised, is the blog about 2NF.
The 2NF Rule states: "An attribute must depend upon its entity's entire UID". This basically means that every one of the attributes is functionally dependent on the whole key. Also, implicit to this rule is the fact that the entitiy is in its 1NF. So, if you have forgotten what 1NF is all about, review yesterday's blog. 
Consider the following example:
The attribute Warehouse_Location is not functionally dependent on Emp_ID. To make this Entity Relationship Diagram in 2NF, move the attribute Warehouse_Location to the entity Warehouse. To be compliant with the 1NF, Warehouse_Location is put in its basic form as Warehouse_Address1, Warehouse_City, Warehouse_State, Warehouse_ZIPCode.
This will result in:
Tomorrow's blog is the last installment of this series on the First 3 Rules of Normalization.
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