จงหาจำนวนสุนัขที่นักเรียนหญิงเลี้ยงไว้ (เพศ F) ไม่จำเป็นต้องใช้โต๊ะทั้งหมด
Find the number of dog pets that are raised by female students (with sex F).It is not neccessary to use all the tables.
 has_pet:  (stuid [ VARCHAR ] petid [ VARCHAR) ]
SELECT COUNT(*) FROM student AS T1 JOIN has_pet AS T2 ON T1.stuid = T2.stuid JOIN pets AS T3 ON T2.petid = T3.petid WHERE T1.sex = 'F' AND T3.pettype = 'dog'