MySQL UNION Operator
MySQL UNION Operator
The UNION operator is used to combine the result-set of two or more SELECT statements.
- Each SELECT statement within UNION must have the same number of columns
- The columns must also have similar data types
- The columns in each SELECT statement must also be in the same order
Example:
Basic Query:
SELECT column_name(s) FROM table1 UNION SELECT column_name(s) FROM table2;
Query Example 1:
SELECT City FROM Customers UNION SELECT City FROM Suppliers ORDER BY City;
Query Example 2:
SELECT City, Country FROM Customers
WHERE Country=‘Germany’
UNION
SELECT City, Country FROM Suppliers
WHERE Country=‘Germany’
ORDER BY City;
