How to use SQL UNION

UNION is use for join multiple SELECT query in one result

Note :

1. Each column match with Each select query column

2. Each column datatype match with Each select query column

3. Each column order match with each select query

UNION Syntax

SELECT YourColumnName FROM YourTableName
UNION
SELECT YourColumnName FROM YourTableName

Example

SELECT CityName FROM Employee
UNION
SELECT CityName FROM Manager
ORDER BY CityName