EXL Service Interview Question
1) What is the difference between a primary key and a unique key? 2) How do you use 'join' in SQL?
Interview Answer
Anonymous
Jun 30, 2021
1) A primary key and a unique key are the same only that a unique key can include Null/NaN values. 2) For example, if you have two datasets you can join them based on a related column they have. In other words you map the tables to a new table where you consolidate the information from the two tables.
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