在“成绩”表中,检索选修4门以上课程的男生的姓名和平均成绩。“成绩”表中包含学号、姓名、课
SELECT姓名,AVG(成绩)AS平均成绩FROM成绩;
WHERE性别=”男”:
GROUPBY学号:
__________COUNT(﹡)>=4。
SELECT姓名,AVG(成绩)AS平均成绩FROM成绩;
WHERE性别=”男”:
GROUPBY学号:
__________COUNT(﹡)>=4。
检索选修4门以上课程的学生总成绩(不统计不及格的课程),并要求按总成绩的降序排列出来。正确的SELECT语句是
设有如下四个基本表S,C,SC,T,结构如图所示。((1)用SQL的DDL语言创建S表,S#为主码,SN不能为空。 (2)创建计算机系学生的视图,该视图的属性列由学号、姓名、课程号和任课教师号组成。 (3)检索计算机系年龄在20岁以上的学生学号。 (4)检索姓王的教师所讲课程的课程号及课程名称。 (5)检索张三同学所学课程的成绩,列出SN、C#和GR。 (6)检索选修总收入超过1000元的教师所讲课程的学生姓名、课程号和成绩。 (7)检索没有选修C1课程且选修课程数为两门的学生的姓名和平均成绩,并按平均成绩降序排列。 (8)检索选修和张三同学所选课程中任意一门相同的学生姓名、课程名。 (9)S1同学选修了C3,将此信息插入SC表中。 (10)删除S表中没有选修任何课程的学生记录。
A、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade DESC;
B、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 and COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC;
C、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade;
D、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 HAVING COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC;
A、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 and COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC
B、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 HAVING COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC
C、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade
D、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade DESC
A、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade DESC
B、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade
C、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 HAVING COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC
D、SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 and COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC
示专业列,过滤掉重复行。 2 )统计有学生选修的课程门数。 3 )求选修 C004 课程的学生的平均年龄。 4 )求学分为 3 的每门课程的学生平均成绩。 5 )统计每门课程的学生选修人数,超过 3 人的课程才统计。要求输出课程号和选修人数,查询结果按人数降序排列,若人数相同,按课程号升序排列。 6 )检索姓王的学生的姓名和年龄。 7 )在选课表中检索成绩为空值的学生学号和课程号。 8 )查询没有学生选修的课的课程号和课程名。 9 )求年龄大于女同学平均年龄的男学生姓名和年龄。 10 )求年龄大于所有女同学年龄的男学生姓名和年龄。 11 )查询所有与王华同年级、同专业,但比王华年龄大的学生的姓名、年龄和性别。 12 )检索选修课程 C002 的学生中成绩最高的学生的学号。 13 )检索学生姓名及其所选修课程的课程号和成绩。 14 )检索选修 4 门以上课程的学生总成绩 ()
已知选课关系SC(S# char(8), C# char(8), GRADE integer),S#学号,C#课程号,GRADE成绩。检索选修4门以上课程的学生总成绩(不统计不及格的课程),并要求按总成绩的降序排列出来。正确的SELECT语句是_________。 A.SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade B.SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 HAVING COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC C.SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 and COUNT(*)>=4 GROUP BY S# ORDER BY Sgrade DESC D.SELECT S#,SUM(GRADE) as Sgrade FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT(*)>=4 ORDER BY Sgrade DESC
A.SELECTS.学号,姓名,平均成绩FROMS,SCWHERES.学号=SC.学号GROUPBYS.学号HAVINGCOUNT(*)>=5ORDERBY平均成绩DESC
B.SELECT学号,姓名,AVG(成绩)FROMS.SCWHERES.学号=SC.学号ANDCOUNT(*)>=5GROUPBY学号ORDERBY3DESC
C.SELECTS.学号,姓名,AVG(成绩)AS平均成绩FROMS,SCWHERES.学号=SC.学号ANDCOUNT(*)>=5GROUPBYS.学号ORDERBY平均成绩DESC
D.SELECTS.学号,姓名,AVG(成绩)平均成绩FROMS,SCWHERES.学号=SC.学号;GROUPBYS.学号HAVINGCOUNT(*)>=50RDERBY3DESC
A.检索开课在3门以上的开课系名、课程名称和选修人数
B.检索选修了3门课程以上的学生记录,显示结果包括课程名称、开课系名和选修人数
C.检索每门课程中,有3人以上选修该课程的记录,显示结果包括课程名称、开课系名和选修人数
D.检索选修人数最多的3门课程的记录,显示结果包括课程名称、开课系名和选修人数
请将下面的SQL语句补充完整。
SELECT学号,SUM(成绩)FROM【 】;
WHERE成绩>=60;
GROUP BY学号;
【 】COUNT(*)>=3
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