Task: Text to Code
Input (English): Step 1: For each row in airlines table, find the corresponding rows in airports table.
Step 2: find the number of rows in the results of step 1 whose airports's Country equals United Airlines and Airline equals AHD
Output (English): SELECT Count ( * ) FROM airlines AS T1 JOIN airports AS T2 WHERE T2.Country = "United Airlines" AND T1.Airline = "AHD"