Difference between UNION and UNION ALL in SQL.

In Today's article, we shall be talking about the UNION operator, and the UNION_ALL operator, how to use them, the difference between the Union operator and the Union all Operator, and Lastly which one is better to use.

What is the UNION  operator and how does it work? 

Union operator allows us to combine two or more results from multiple SELECT queries into a single unified result set. It has a default feature to remove the duplicate rows from the tables. By using the UNION operator it means you are selecting a particular column of two different tables. So it returns the result.