笔试-822-aqy

第一题

sql题，查找选课女生最多的三个课程的名字及对应选课的女生数量

SELECT subinfo.name,COUNT(*) AS girl_count
        FROM Student_Info s JOIN Subject_Register sub
        ON s.id=sub.student_id
        JOIN Subject_Info subinfo
        ON sub.subject_id=subinfo.id
        WHERE s.gender=2
        GROUP BY sub.subject_id
        ORDER BY girl_count DESC
        LIMIT 3

第二题

leetcode1116

第三题

leetcode51