Sunday, November 6, 2011

Database Normalization: What to test for Second Normal Form?

In the last post, Database Normalization: What to test for First Normal Form?, I explained database normalization briefly. You also saw the tests that should be executed to check the first normal form (1NF). In this post, let us understand the second normal form (2NF) and the tests that need to be executed for checking it. View my video on Second Normal Form with examples or read on...
A table that is in 2NF is already in 1NF. Additionally, each column that is not part of any candidate key depends on the entire candidate key (and not a part of it). Now, let us see the examples of some tables that are not in 2NF and how to convert them to 2NF.