MySQL EXISTS

The MySQL EXISTS Operator

The EXISTS operator in MySQL is used to check for the existence of any record in a subquery.

It returns TRUE if the subquery returns one or more records.

SELECT column_name(s)
FROM table_name
WHERE EXISTS
(SELECT column_name FROM table_name WHERE condition);

Here is a portion of the “Products” table in the Northwind sample database:

Here is a portion of the “Suppliers” table:

The following SQL statement returns TRUE and lists the suppliers who have products priced less than 20:

SELECT SupplierName
FROM Suppliers
WHERE EXISTS (SELECT ProductName FROM Products WHERE Products.SupplierID = Suppliers.supplierID AND Price < 20);

The following SQL statement returns TRUE and lists the suppliers who have products priced exactly at 22:

SELECT SupplierName
FROM Suppliers
WHERE EXISTS (SELECT ProductName FROM Products WHERE Products.SupplierID = Suppliers.supplierID AND Price = 22);