แสดงภาพแผนภูมิวงกลมว่ามีกี่ชั้นเรียนในแต่ละแผนก?ไม่จำเป็นต้องใช้ตารางทั้งหมด
Visualize a pie chart with how many classes are held in each department?It is not neccessary to use all the tables.
 CLASS:  CLASS_CODE [ varchar(5)]  CRS_CODE [ varchar(10)]  CLASS_SECTION [ varchar(2)]  CLASS_TIME [ varchar(20)]  CLASS_ROOM [ varchar(8)]  PROF_NUM [ int] 
SELECT DEPT_CODE, COUNT(*) FROM CLASS AS T1 JOIN COURSE AS T2 ON T1.CRS_CODE = T2.CRS_CODE GROUP BY DEPT_CODE