Subqueries with NOT EXISTS
NOT EXISTS works like EXISTS, except the WHERE clause in which it is used is satisfied if no rows are returned by the subquery.
For example, to find the names of products that are not in the wheels subcategory:
USE AdventureWorks;
GO
SELECT Name
FROM Production.Product
WHERE NOT EXISTS
(SELECT *
FROM Production.ProductSubcategory
WHERE ProductSubcategoryID =
Production.Product.ProductSubcategoryID
AND Name = 'Wheels')
See Also
Other Resources
EXISTS (Transact-SQL)
NOT (Transact-SQL)