Intro to Database Systems Week 3

1. Someone described normalization rule as "a non-key column depends on the key, the whole key, and nothing but the key, so help me Codd." Key refers a primary or other candidate key of a table. If the key has multiple columns, then "whole key" means all columns together and not just some part of the key. Explain in your words what 3rd normal form is and why it is important.

    Third normal form is when a candidate key in a table depends on all other columns in the table to be unique. Third normal form is important because it helps reduce the duplication of data in a table.


2. What is an SQL view. How is it similar to a table? In what ways is it different?

    An SQL view is a table that's associated with a SELECT query. Views are similar to tables in that they can be queried in SELECT statements using FROM. They are different because a view doesn't store table data, it is a saved query statement that references data from other tables. 

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