CREATE TABLE CLASS (crs_code VARCHAR(255)); CREATE TABLE course (dept_code VARCHAR(255), crs_credit INTEGER, crs_code VARCHAR(255))
Find the total credits of all classes offered by each department.
    
SQL: SELECT SUM(T1.crs_credit), T1.dept_code FROM course AS T1 JOIN CLASS AS T2 ON T1.crs_code = T2.crs_code GROUP BY T1.dept_code