Task: Text to Code
Input (English): Step 1: For each row in appellations table, find the corresponding rows in wine table.
Step 2: find the average Price in the results of step 1 whose appellations's State equals Sonoma
Output (English): SELECT Avg ( T2.Price ) FROM appellations AS T1 JOIN wine AS T2 ON T1.Appelation = T2.Appelation WHERE T1.State = "Sonoma"