A: SELECT S
B: , SNAME FROM SC GROUP BY S
C: SELECT S
D: FROM SC GROUP BY S
E: HAVING COUNT(*)>3
F: SELECT S
G: ,Cname FROM SC GROUP BY S
H: WHERE COUNT(*)>3
I: SELECT S
J: FROM SC WHERE COUNT(*)>3 GROUP BY S
举一反三
- 下列查询语句中，错误的是（）。 A: SELECT Sno， COUNT（*） FROM SC GROUP BY Sno B: SELECT Sno FROM SC GROUP BY Sno WHERE COUNT（*）> 3 C: SELECT Sno FROM SC GROUP BY Sno HAVING COUNT（*）> 3 D: SELECT Sno FROM SC GROUP BY Sno
- 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
- 查询选修了2门课程以上的学生学号（） A: select sid,count(*) from sc group by sid having count(*)>=2 B: select sid,count(*) from sc group by sid where count(*)>=2 C: select sid,count(*) from sc where count(*)>=2 group by sid D: select sid,count(*) from sc group by cid having count(*)>=2
- 查询选修了课程号为‘C2’的学生号和姓名,若用下列SQL的SELECT语句表达时, 是错误的? A: SELECT S.S B: ,SNAME FROM S WHERE S C: = (SELECT SS D: FROM SC WHERE C E: =‘C2’) F: SELECT S.S G: ,SNAME FROM S,SC WHERE S H: = SS I: AND C J: =‘C2’ K: SELECT S.S L: ,SNAME FROM S,SC WHERE S M: = SS N: AND C O: =‘C2' ORDER BY S P: Q: SELECT S.S R: ,SNAME FROM S WHERE S S: IN(SELECT SS T: FROM SC WHERE C U: =‘C2' )
- 查询选修了课程号为“C1”的学生的姓名和年龄，若用下列SQL的SELECT语句表达时，错误的是( )。 A: SELECT SNAME，AGE FROM S WHERE B: S#=(SELECT S C: S#FROM SC WHERE D: C#='C1') E: SELECT SNAME，AGE FROM S，SC WHERE F: S#=S G: S# AND S H: C#='C1' I: SELECT SNAME，AGE FROM S，SC WHERE J: S#=S K: S# AND S L: C#='C1' ORDERBY M: S# N: SELECT SNAME，AGE FROM S WHERE O: S#=(SELECT S P: S# FROM SC WHERE S Q: C#='C1')
内容
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检索选修课程‘C2’的学生中成绩最高的学生的学号。正确的select语句为（ ）。 A: select S B: from sc where C C: =‘C2’and grade>= (select grade from sc where C D: =‘C2’) E: select S F: from sc where C G: =‘C2’and grade in (select grade from sc where C H: =‘C2’) I: select S J: from sc where C K: =‘C2’and grade not in (select grade from sc where C L: =‘C2’) M: select S N: from sc where C O: =‘C2’and grade>=all (select grade from sc where C P: =‘C2’)
- 1
设有关系S(S#,SNAME,AGE,SEX)、C(C#,CNAME,TEACHER)和SC(S#,C#,GRADE)，请将实现以下功能的SQL语句填写完整：[br][/br] （4）检索全部学生都选修的课程的课程号(C#)和课程名(CNAME)。 [br][/br] 方法1： SELECT C#,CNAME FROM C WHERE (SELECT * FROM S WHERE (SELECT * FROM SC WHERE C.C#=SC.C# AND S.S#=SC.S#)) 方法2： select c#,cname from c where c# in( select c# from sc group by having count(distinct s#)=(select count(*) from ))
- 2
有关系S(S#，SNAME，SAGE)，C(C#，CNAME)，SC(S#，C#，GRADE)。若要查找分数(grade)不及格的学生姓名(sname)，则以上正确的有？（ ） A: SELECT sname FROM s, sc WHERE grade<60 B: SELECT sname FROM s WHERE sno IN(SELECT Cno FROM sc WHERE grade<60) C: SELECT sname FROM s, sc WHERE s.sno=sc.sno AND grade<60 D: SELECT sname FROM s, sc WHERE s.sno=sc.sno OR grade<60
- 3
有关系S(S#，SNAME，SAGE)，C(C#，CNAME)，SC(S#，C#，GRADE)。若要查找分数(grade)不及格的学生姓名(sname)，则以上正确的有？（ ） A: SELECT sname FROM s, sc WHERE grade<60 B: SELECT sname FROM s WHERE sno IN(SELECT Cno FROM sc WHERE grade<60) C: SELECT sname FROM s, sc WHERE s.sno=sc.sno AND grade<60 D: SELECT sname FROM s, sc WHERE s.sno=sc.sno OR grade<60
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检索选修“C2”课程的学生中成绩最高的学生的学号。正确的SELECT语句是（ ）。 A: SELECT s B: FROM sc WHERE c C: =’C2’ AND grade＞＝(SELECT grade FROM sc WHERE c D: =’C2’); E: SELECT s F: FROM sc WHERE c G: =’C2’ AND grade IN(SELECT grade FROM sc WHERE c H: =’C2’); I: SELECT s J: FROM sc WHERE c K: =’C2’ AND grade NOT IN(SELECT grade FORM sc WHERE c L: =’C2’); M: SELECT s N: FROM sc WHERE c O: =’C2’ AND grade＞＝(SELECT max(grade) FROM sc WHERE c P: =’C2’);