What is union in SQL?

Question

Can anyone explain the union operator in SQL?

Answer 1

In SQL, the Union operator is used to combining the output from multiple SELECT statements. The result-sets of SELECT statements should be the same number of columns, similar data types of columns, and columns should be in the same order.

Here is the syntax for using the UNION operator in SQL:

SELECT column_list from TableA

UNION

SELECT column_list from TableB;

You can check out his SQL tutorial to learn more about the union operator.