有表song(id,song_name,album,play_count,fav_count)分别表示歌曲的主键id、歌曲名、专辑名、播放次数和收藏次数。要求查询超过两首歌的专辑与其歌曲数，并且按专辑名排序；有同学给出如下sql语句： select id,count(*) from song order by albumgroup[br][/br]by album having count(*)>2 ; 这个sql错误的地方是：
A: order by 后面跟group by语句
B: album没有出现在select语句中
C: 在having条件中使用了count(*)
D: 这个sql语句没有错误
A: order by 后面跟group by语句
B: album没有出现在select语句中
C: 在having条件中使用了count(*)
D: 这个sql语句没有错误
举一反三
- 有表song(id,song_name,album,play_count,fav_count)分别表示歌曲的主键id、歌曲名、专辑名、播放次数和收藏次数，以下与order by相关的sql错误的是： A: select * from song order by play_count asc; B: select * from song order by (play_count + fav_count) asc; C: select * from song order by fav_count desc where play_count > 5; D: select * from song order by id,play_count asc,fav_count desc;
- 统计每个部门中人数的语句是？ A: select count(id) from emp order by deptno; B: select sum(id) from emp order by deptno; C: select count(id) from emp group by deptno; D: select sum(id) from emp group by deptno;
- 统计每个部门中的人数的语句是【】。 A: SELECT SUM(ID) FROM examp GROUP BY DE_NUM B: SELECT COUNT(ID) FROM examp ORDER BY DE_NUM C: SELECT COUNT(ID) FROM examp GROUP BY DE_NUM D: SELECT SUM(ID) FROM examp ORDER BY DE_NUM
- 若要求“查询选修了3门以上课程的学生的学号”,正确的SQL语句是( ) A: SELECT sNo FROM SC GROUP BY sNo WHERE COUNT(*)> 3 B: SELECT sNo FROM SC GROUP BY sNo HAVING COUNT(*)> 3 C: SELECT sNo FROM SC ORDER BY sNo WHERE COUNT(*)> 3 D: SELECT sNo FROM SC ORDER BY sNo HAVING COUNT(*)> 3
- 统计各系男生人数,最准确的SQL语句是(<br/>)。 A: SELECT<br/>COUNT(*) FROM stduents GROUP BY d_no WHERE sex='男' B: SELECT<br/>COUNT(*) FROM students WHERE sex='男'<br/>GROUP BY d_no C: SELECT<br/>COUNT(*) FROM students WHERE sex='男'<br/>ORDER BY d_no D: SELECT<br/>COUNT(*) FROM students HAVING sex='男'<br/>GROUP BY d_no