以下语句错误的是() A: LECT rank, AVG(salary) FROM people HAVING AVG(salary) > 1000 GROUP BY rank; B: SELECT rank, AVG(salary) FROM people GROUP BY rank HAVING AVG(salary) > 1000 C: SELECT rank, AVG(salary) FROM people HAVING AVG(salary) > 1000 GROUP BY rank; D: SELECT AVG(salary) FROM people GROUP BY rank HAVING AVG(salary) > 1000; E: SELECT rank, AVG(salary) FROM people GROUP BY rank WHERE AVG(salary) > 1000;

下列SQL语句中，正确的是（ ）。 A: SELECT S B: , SNAME FROM SC GROUP BY S C: D: SELECT S E: FROM SC GROUP BY S F: HAVING COUNT(*)>3 G: SELECT S H: ,Cname FROM SC GROUP BY S I: WHERE COUNT(*)>3 J: SELECT S K: FROM SC WHERE COUNT(*)>3 GROUP BY S L:

下面哪个语句关于GROUP BY 和HAVING语句的使用是正确的是?() A: SELECT<br/>JOB_ID, DEPARTMENT_ID, AVG(SALARY) FROM EMPLOYEES GROUP BY JOB_ID<br/>HAVING AVG(SALARY) &gt; 3000; B: SELECT<br/>JOB_ID, DEPARTMENT_ID, AVG(SALARY) FROM EMPLOYEES GROUP BY JOB_ID,<br/>DEPARTMENT_ID HAVING AVG(SALARY) &gt; 3000; C: SELECT<br/>JOB_ID, DEPARTMENT_ID, AVG(SALARY) FROM EMPLOYEES GROUP BY<br/>AVG(SALARY) HAVING AVG(SALARY) &gt; 3000; D: FROM<br/>EMPLOYEES GROUP BY JOB_ID, DEPARTMENT_ID HAVING SALARY &gt; 3000;

在学生选课数据库中，查询平均成绩大于等于60分的同学，SQL语句为（ ） A: SELECT Sno, AVG(Grade) FROM SC GROUP BY Sno HAVING AVG(Grade)&gt;=60; B: SELECT Sno FROM SC WHERE Grade&gt;=60 GROUP BY Sno; C: SELECT Sno, Grade FROM SC GROUP BY Sno HAVING AVG(Grade)&gt;=60; D: SELECT Sno FROM SC GROUP BY Sno HAVING Grade &gt;=60;

查询最少选修了3门课程的学生学号和姓名，正确的SQL语句是（）。 A: SELECT 学号,姓名,COUNT(*) FROM 选课成绩 WHERE COUNT(*)&gt;=3 GROUP BY 学号 B: SELECT 学号,姓名,COUNT(*) FROM选课成绩 WHERE COUNT(*)&gt;=3 GROUP BY学号,姓名 C: SELECT 学号,姓名,COUNT(*) FROM 选课成绩 GROUP BY学号HAVING COUNT(*)&gt;=3 D: SELECT 学号,姓名,COUNT(*) FROM 选课成绩 GROUP BY学号,姓名 HAVING COUNT(*)&gt;=3

查询最低成绩大于85分的学生学号和平均成绩,可以使用的查询语句是:　 。 A: SELECT Sno, AVG(Grade) FROM SC HAVING MIN(Grade) &gt; 85 GROUP BY Sno; B: SELECT Sno, AVG(Grade) FROM SC GROUP BY Sno HAVING MIN(Grade) &gt; 85; C: SELECT Sno, AVG(Grade) FROM SC WHERE MIN(Grade) &gt; 85 GROUP BY Sno; D: SELECT Sno, AVG(Grade) FROM SC GROUP BY Sno WHERE MIN(Grade) &gt; 85;

针对学生选课表sc（sno, cno, grade），其中sno为学号，cno为课程号，grade为成绩。以下（ ）语句可查询选修了两门以上成绩在90分以上课程的学生学号。 A: select sno from sc where grade&gt;90 group by sno having count(cno)&gt;2; B: select sno from sc where grade&gt;90 group by sno having count(*)&gt;2; C: select sno from sc where grade&gt;90 and count(*)&gt;2 group by sno; D: select sno from sc where grade&gt;90 group by sno having count(sno)&gt;2;

有一个“成绩”表，包含学号、课程号、成绩三个字段。要求查询2科以上不及格(包括2科）学生信息。显示学号、不及格课程数。对应的SQL语句为（ ） A: select 学号,count(*) as 不及格课程数 from 学生 having 成绩&lt;60 group by 学号 where count(*)&gt;=2 B: select 学号,count(*) as 不及格课程数 from 学生 where 成绩&lt;60 group by 学号 where count(*)&gt;=2 C: select 学号,count(*) as 不及格课程数 from 学生 where 成绩&lt;60 group by 学号 having 不及格课程数&gt;=2 D: select 学号,count(*) as 不及格课程数 from 学生 where 成绩&lt;60 group by 学号 having count(*)&gt;=2

在 HTML5 中，哪个元素用于组合标题元素( ) ？ A: &lt;group&gt; B: &lt; header&gt; C: &lt;headings&gt; D: &lt;hgroup&gt;

订单表tb_order包含用户信息uid和产品信息pid等属性列,以下语句能够返回至少被订购过三次的pid是()。 A: SELECT<br/>pid FROM tb_order WHERE count(pid)&gt;3; B: SELECT<br/>pid FROM tb_order WHERE max(pid)&gt;=3; C: SELECT<br/>pid FROM tb_order GROUP BY pid HAVING COUNT(pid)&gt;3; D: SELECT<br/>pid FROM tb_order GROUP BY pid HAVING COUNT(pid)&gt;=3;