关系SC(Sno，Cno，Grade)表示学号、课程号、成绩。现要查询最高分在91分以上的学生的学号和平均成绩，正确的语句是______。
A: SELECT Sno，MAX(Grade)
FROM SC
WHERE MAX(Grade)≥91
GROUP BY Sno
B: SELECT Sno，MAX(Grade)
FROM SC
GROUP BY Sno
HAVING MAX(Grade)≥91
C: SELECT Sno，MAX(Grade)
FROM SC
WHERE MAX(Grade)≥91
ORDER BY Sno
D: SELECT Sno，MAX(Grade)
FROM SC
GROUP BY Cno
HAVING MAX(Grade)≥91
A: SELECT Sno，MAX(Grade)
FROM SC
WHERE MAX(Grade)≥91
GROUP BY Sno
B: SELECT Sno，MAX(Grade)
FROM SC
GROUP BY Sno
HAVING MAX(Grade)≥91
C: SELECT Sno，MAX(Grade)
FROM SC
WHERE MAX(Grade)≥91
ORDER BY Sno
D: SELECT Sno，MAX(Grade)
FROM SC
GROUP BY Cno
HAVING MAX(Grade)≥91
举一反三
- 关系SC(Sno，Cno，Grade)表示学号，课程号，成绩。现要查询最高分在91分以上的学生的学号和平均成绩，正确的语句是______。 A: SELECT Sno，MAX(Grade) FROM SC WHERE MAX(Grade)＞=91 GROUP BY Sno B: SELECT Sno，MAX(Grade) FROM SC GROUP RY Sno HAVING MAX(Grade)＞=91 C: SELECT Sno，MAX(Grade) FROM SC WHERE MAX(Grade)＞=91 ORDER BY Sno D: SELECT Sno，MAX(Grade) FROM SC GROUP BY Cno HAVING MAX(Grade)＞=91
- 针对表SC（sno, cno, grade），其中sno为学号，cno为课程号，grade为成绩。以下哪个操作（ ）统计出每位学生所选课程的最高分和最低分。 A: select sno,max(grade), min(grade) from sc B: select sno,max(grade), min(grade) from sc order by sno C: select sno,max(grade), min(grade) from sc group by sno D: select sno,avg(grade), sum(grade) from sc group by sno
- 表sc中存放了多个学生的多门课程的成绩，sno为学号，cno为课程号，grade为成绩。要查询平均分最高的学生学号和平均分，下列（）语句可以实现。 A: SELECT top 1 sno,avg(grade) FROM sc group by sno order by avg(grade) desc B: SELECT sno,max(avg(grade)) FROM sc group by sno C: SELECT sno,max(grade), avg(grade) FROM sc group by sno D: SELECT sno,max(grade) FROM sc group by sno
- 已知关系模式：sc(sno,sname,grade)，各属性含义依次为学号、课程名、分数。要查找“数据库”课分数最高的学生的学号，正确的SQL语句是 A: SELECT sno FROM sc WHERE sname = "数据库" AND grade = MAX(grade) B: SELECT sno FROM sc FOR sname = "数据库" OR grade＞=MAX(grade) C: SELECT sno FROM sc WHERE sname = "数据库" AND grade = (SELECT MAX(grade) FROM sc) D: SELECT sno FROM sc FOR sname = "数据库" OR grade = (SELECT MAX(grade) FROM sc)
- 已知关系模式：SC(sno,sname,grade)，各属性含义依次为学号、课程名、分数。要查找“数据库”课分数最高的学生的学号，正确的SQL语句是( )。 A: SELECT sno FROM sc WHERE sname="数据库"AND grade=MAX(grade) B: SELECT sno FROM sc FOR sname="数据库"OR grade＞=MAX(grade) C: SELECT sno FROM sc WHERE sname="数据库"AND grade=(SELECT MAX(grade)FROM sc) D: SELECT sno FROM sc FOR sname="数据库"OR grade=(SELECT MAX(grade)FROM s