For in the above example city1 and city2 are repeating.In order that this table to be in First normal form you have to modify the table structure as follows.Also not that the Customer Name is now broken down to first name and last name (First normal form data should be broken down to smallest unit).
Second Normal form The second normal form states that each field in a multiple field primary keytable must be directly related to the entire primary key. Or in other words, each non-key field should be a fact about all the fields in the primary key. In the above table of customer, city is not linked to any primary field.
That takes our database to a second normal form. Third normal form A non-key field should not depend on other Non-key field. The field "Total" is dependent on "Unit price" and "qty". So now the "Total" field is removed and is multiplication of Unit price * Qty.
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