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SCRUMble ! - New Book about SCRUM

 SCRUMble ! Hello Blog Readers! Thank you for all your support and encouragement. I have something exciting for you all. I have recently written and published a new book called 'SCRUMble !'. It is currently available on pothi store. It will be soon available on Amazon and Flipkart as well. Please get your copy and do let me know your reviews. -Abhishek Sathe SCRUMble ! Written and Published by: Abhishek Sathe                                                                              Distributed by: pothi.com Order your copy now:  https://store.pothi.com/book/abhishek-sathe-scrumble/ Coming soon on Amazon and Flipkart About the book: Scrum is a framework for solving complex problems largely adapted by Software Development field. There are multiple ag...
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Database Normalization 101

Database Normalization was developed by IBM researcher E.F. Codd In the 1970s and is a process of increasing clarity in database schema by dividing larger relations (or tables) into smaller relations in order to lower duplication and reduce dependency of data. 

 Normal Forms are a set of rules to achieve database normalization.

 First Normal Form (1NF):

 Consider following table.
To convert a table in 1NF, each record needs to be unique and each cell should contain single value.
After converting above table in 1NF, it looks like:


Second Normal Form (2NF):

 To convert a table in 2NF, it should be in 1NF and should have a one column as primary key.

 .After converting above table in 2NF, we get:

Third Normal Form (3NF):
To convert a table in 3NF, it should be in 2NF and should have a no transitive functional dependencies.

 A transitive functional dependency exists in a table when a change in one non-primary key column may cause a change in other column. For example, if Madhuri Bose gets married then her name will change. This change in Name column will cause a change in her salutation from Ms to Mrs. Thus, it has transitive functional dependency.

 After converting above table in 2NF, we get:
Now all above tables are normalized and cannot be decomposed further.
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