Using multiple table expressions

A single WITH clause may define more than one common table expression. These definitions must be separated by commas. The following example lists the department that has the smallest payroll and the department that has the largest number of employees.

WITH
  CountEmployees( DepartmentID, n ) AS
    ( SELECT DepartmentID, COUNT( * ) AS n
      FROM Employees GROUP BY DepartmentID ),
  DeptPayroll( DepartmentID, amt ) AS
     ( SELECT DepartmentID, SUM( Salary ) AS amt
       FROM Employees GROUP BY DepartmentID )
SELECT count.DepartmentID, count.n, pay.amt
FROM CountEmployees AS count JOIN DeptPayroll AS pay
ON count.DepartmentID = pay.DepartmentID
WHERE count.n = ( SELECT MAX( n ) FROM CountEmployees )
   OR pay.amt = ( SELECT MIN( amt ) FROM DeptPayroll );

Using multiple table expressions

See also