SELECT COUNT(*), T3.dorm_name FROM student AS T1 JOIN lives_in AS T2 ON T1.stuid = T2.stuid JOIN dorm AS T3 ON T3.dormid = T2.dormid WHERE T1.age > 20 GROUP BY T3.dorm_name
Temukan jumlah siswa yang lebih tua dari 20 di setiap asrama.
CREATE TABLE dorm (dorm_name VARCHAR, dormid VARCHAR); CREATE TABLE lives_in (stuid VARCHAR, dormid VARCHAR); CREATE TABLE student (stuid VARCHAR, age INTEGER)