มีร้านค้ากี่แห่งที่มีสำนักงานใหญ่ในแต่ละเมือง ลงจุดเป็นแผนภูมิแท่ง ไม่จำเป็นต้องใช้ตารางทั้งหมด
How many stores are headquarted in each city. Plot them as bar chart.It is not neccessary to use all the tables.
 district:  District_ID [ int]  District_name [ text]  Headquartered_City [ text]  City_Population [ real]  City_Area [ real] 
SELECT Headquartered_City, COUNT(*) FROM store AS t1 JOIN store_district AS t2 ON t1.Store_ID = t2.Store_ID JOIN district AS t3 ON t2.District_ID = t3.District_ID GROUP BY t3.Headquartered_City