SELECT b.cname, COUNT(*) AS [cnt] FROM student AS a JOIN course AS b ON a.cid=b.cid GROUP BY b.cname ORDER BY COUNT(*) DESC;
SELECT b.cname,COUNT(a.cid) 次数 FROM 学生表 a,课程表 b ON a.cid=b.cid GROUP BY b.cname ORDER BY COUNT(a.cid) DESC;
先聚合再连表,获取较高性能。 select a.* from course a inner join (select count(*) cnt,cid from student group by cid) b on a.cid=b.cid order by cnt desc
select a.cname from course a left join student b on b.cid=a.cid group by a.cname order by count(*) desc
select a.cname , count(*) cnt from 课程表 a, 学生表 b where a.cid = b.cid group by a.cname order by cnt desc
学生表 student sid,cid 课程表 course cname,cid select cname from ( select cid,count(*) selNum from student group by cid ) a join course b on a.cid=b.cid order by a.selNum desc
select cname from course order by (select count(*) from student where cid=course.cid) desc
select b.cname,count(b.cname)as num from student a,course b where a.cid=b.cid group by cname order by num
没看到是降序~~ select b.cname,count(b.cname)as num from student a,course b where a.cid=b.cid group by cname order by num desc
SELECT b.cname, COUNT(*) AS [cnt] FROM student AS a JOIN course AS b ON a.cid=b.cid GROUP BY b.cname ORDER BY COUNT(*) DESC;
select cname from course c join student s on c.cid=s.cid group by c.cname order by count(1) desc
select a.cname , count(*) cnt from student a join course b on a.cid = b.cid group by a.cname order by cnt desc
b.cname,
COUNT(*) AS [cnt]
FROM student AS a
JOIN course AS b
ON a.cid=b.cid
GROUP BY b.cname
ORDER BY COUNT(*) DESC;
SELECT
b.cname,COUNT(a.cid) 次数 FROM 学生表 a,课程表 b ON a.cid=b.cid
GROUP BY b.cname
ORDER BY COUNT(a.cid) DESC;
select a.* from course a
inner join
(select count(*) cnt,cid from student group by cid) b
on a.cid=b.cid
order by cnt desc
select a.cname from course a
left join student b on b.cid=a.cid
group by a.cname
order by count(*) desc
select a.cname , count(*) cnt from 课程表 a, 学生表 b where a.cid = b.cid group by a.cname order by cnt desc
课程表 course cname,cid select cname from (
select cid,count(*) selNum from student
group by cid
) a join course b on a.cid=b.cid
order by a.selNum desc
select b.cname,count(b.cname)as num
from student a,course b
where a.cid=b.cid
group by cname
order by num
没看到是降序~~
select b.cname,count(b.cname)as num
from student a,course b
where a.cid=b.cid
group by cname
order by num desc
SELECT
b.cname,
COUNT(*) AS [cnt]
FROM student AS a
JOIN course AS b
ON a.cid=b.cid
GROUP BY b.cname
ORDER BY COUNT(*) DESC;
from course c
join student s
on c.cid=s.cid
group by c.cname
order by count(1) desc
on a.cid = b.cid group by a.cname order by cnt desc