Find the names and number of works of the three artists who have produced the most songs.
SELECT T1.artist_name ,  count(*) FROM artist AS T1 JOIN song AS T2 ON T1.artist_name  =  T2.artist_name GROUP BY T2.artist_name ORDER BY count(*) DESC LIMIT 3
names of artists = artist_name; number of works = COUNT(*); produced the most songs = MAX(COUNT(song)); three artists = LIMIT 3;