How many actors have appeared in each musical?
SELECT T2.Name ,  COUNT(*) FROM actor AS T1 JOIN musical AS T2 ON T1.Musical_ID  =  T2.Musical_ID GROUP BY T1.Musical_ID
SELECT T2.Name ,  COUNT(*) FROM actor AS T1 JOIN musical AS T2 ON T1.Musical_ID  =  T2.Musical_ID GROUP BY T1.Musical_ID
[{'Name': 'The Phantom of the Opera', 'COUNT(*)': 2}, {'Name': 'Les Misérables', 'COUNT(*)': 2}, {'Name': 'West Side Story', 'COUNT(*)': 1}, {'Name': 'The Book of Mormon', 'COUNT(*)': 4}]