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
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)<br> FROM SC<br> WHERE MAX(Grade)≥91<br> GROUP BY Sno B: SELECT Sno，MAX(Grade)<br> FROM SC<br> GROUP BY Sno<br> HAVING MAX(Grade)≥91 C: SELECT Sno，MAX(Grade)<br> FROM SC<br> WHERE MAX(Grade)≥91<br> ORDER BY Sno D: SELECT Sno，MAX(Grade)<br> FROM SC<br> GROUP BY Cno<br> 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
内容
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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)>=60; B: SELECT Sno FROM SC WHERE Grade>=60 GROUP BY Sno; C: SELECT Sno, Grade FROM SC GROUP BY Sno HAVING AVG(Grade)>=60; D: SELECT Sno FROM SC GROUP BY Sno HAVING Grade >=60;
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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(grad B: SELECT sno FROM sc FOR sname="数据库"OR grade＞=MAX(grad C: SELECT sno FROM sc WHERE sname="数据库"AND grade=(SELECT MAX(grad FROM s D: SELECT sno FROM sc FOR sname="数据库"OR grade=(SELECT MAX(grad FROM s
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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) > 85 GROUP BY Sno; B: SELECT Sno, AVG(Grade) FROM SC GROUP BY Sno HAVING MIN(Grade) > 85; C: SELECT Sno, AVG(Grade) FROM SC WHERE MIN(Grade) > 85 GROUP BY Sno; D: SELECT Sno, AVG(Grade) FROM SC GROUP BY Sno WHERE MIN(Grade) > 85;
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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 shame="数据库"AND. grade=(SELECT MAX(grade)FROM sc) D: SELECT son FROM SC. FOR sname="数据库"OR grade=(SELECT MAX(grade. FROM sc)
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查询所有有成绩的学生学号和课程号。正确的SELECT语句是（）。 A: Select sno , cno from sc where grade < > null B: Select sno as 学号, cno as 课程号 from sc where grade is not null C: Select sno , cno from sc where grade !=‘ ’ D: Select sno , cno from sc where grade is not null