SQL: UNION Operator














The UNION operator combines two or more SELECT statements into one result set. The SELECT list must be the same in all queries, same columns, expressions, functions, and data types. All UNION queries can be replaced with a join query. The query below combines the Customers select statement with with the Employees statement

SELECT City,Address
FROM Customers
UNION
SELECT City,Address
FROM Employees

Here is the result:



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