Task: Text to Code
Input (English): Step 1: find the SupportRepId of Customer table for which Customer's LastName greater than 20.
Step 2: find the Employee's LastName of Employee table whose Employee's LastName not one of the results of step 1
Output (English): SELECT T1.LastName FROM Employee AS T1 WHERE T1.LastName NOT IN ( SELECT T2.SupportRepId FROM Customer AS T2 WHERE T2.LastName > 20 )