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edits
Changes
→First normal form
* Identify each set of related data with a primary key
Examples:<br>
https://www.quora.com/What-is-the-difference-between-NF-2NF-and-3NF<br>
# Atomic means the column only stores one thing. A column called, FullName, which stores the customer’s first & last name is not atomic. You should have 2 atomic columns, one for FirstName, and another for LastName. Columns storing comma-separated values are also non-atomic.
# If you’ve ever seen Phone1, Phone2, and Phone3 in your Customers table (each phone column more sparse than the prior), then this table contains a Repeating Group, and your junior data architect should have his DDL permissions revoked. But chances are, you don’t have a data architect, and the table was created as an afterthought by your application code developers (who think you’d be better off using MongoDB anyway). Congratulations, your Customers table doesn’t even meet first normal form.
===Second normal form===