三个表学生表S、课程表C 和学生选课表SC,它们的结构如下S(S#,SN,SEX,AGE,DEPT) C(C#,CN) SC(S#,C#,GRADE) 其中:S#为学号,SN 为姓名,SEX 为性别,AGE 为年龄,DEPT 为系别,C#为课程号,CN 为课程名,GRADE 为成绩。 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 语句是
A: ELECT S# FORM SC WHERE C#=’C2’ AND GRAD>=(SELECT GRADE FORM SC WHERE C#=’C2’)
B: SELECT S# FORM SC WHERE C#=’C2’ AND GRADE IN (SELECT GRADE FORM SC WHERE C#=’C2’)
C: SELECT S# FORM SC WHERE C#=’C2’ AND GRADE NOT IN (SELECT GRADE FORM SC WHERE C#=’C2’)
D: SELECT S# FORM SC WHERE C#=’C2’ AND GRADE>=ALL (SELECT GRADE FORM SC WHERE C#=’C2’)
A: ELECT S# FORM SC WHERE C#=’C2’ AND GRAD>=(SELECT GRADE FORM SC WHERE C#=’C2’)
B: SELECT S# FORM SC WHERE C#=’C2’ AND GRADE IN (SELECT GRADE FORM SC WHERE C#=’C2’)
C: SELECT S# FORM SC WHERE C#=’C2’ AND GRADE NOT IN (SELECT GRADE FORM SC WHERE C#=’C2’)
D: SELECT S# FORM SC WHERE C#=’C2’ AND GRADE>=ALL (SELECT GRADE FORM SC WHERE C#=’C2’)
举一反三
- 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语句是______。 A: SELECT S# FORM SC WHERE C#="C2"AND GRADE>=(SELECT GRADE FORM SC WHERE C#="C2") B: SELECT S# FORM SC WHERE C#="C2"AND GRADE IN(SELECT GRADE FORM SC) WHERE C#="C2" C: SELECT S# FORM SC WHERE C#="C2"AND GRADE NOT IN(SELECT GRADE FORM SC WHERE C#="C2") D: SELECT S# FORM SC WHERE C#="C2"AND GRADE>=ALL(SELECT GRADE FORM SC WHERE C#="C2")
- 有学生表S(S#,SN,SEX,AGE,DEPT),课程表C(C#,CN),学生选课表SC(S#,C#,GRADE),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语句是_________。 A: SELECT S# FROM SCWHERE C#="C2" AND GRADE>=(SELECT GRADE FROM SC WHERE C#="C2") B: SELECT S# FROM SCWHERE C#="C2" AND GRADE IN(SELECT GRADE FROM SC WHERE C#="C2") C: SELECT S# FROM SCWHERE C#="C2" AND GRADE NOT IN(SELECT GRADE FROM SC WHERE C#="C2") D: SELECT S# FROM SCWHERE C#="C2" AND GRADE>=ALL
- 题中假定学生关系是S(S#,SN.,SEX,AGE),课程关系是C(C#,CNAME,TEACH-ER),学生选课关系是SC(S#,C#,GRADE)。 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语句是______。 A: SELECT S# FORM SCWHERE C#="C2"AND GRADE>=(SELECT GRADE FORM SCWHERE C#="C2") B: SELECT S# FORM SCWHERE C#="C2"AND GRADE IN(SELECT GRADE FORM SC.WHERE C#="C2" C: SELECT S# FORM SCWHERE C#="C2"AND GRADE NOT IN(SELECT GRADE FORM SCWHERE C#="C2") D: SELECT S# FORM SCWHERE C#="C2"AND GRADE>=ALL(SELECT GRADE FORM SCWHERE C#="C2")
- 假设有三个基本表:学生表S、课程表C、学生选课表SC,它们的结构如下:S(S#,SN,SEX,AGE,DEPT) C(C#,CN) SC(S#,C#,GRADE)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 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”)
- 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语句是( )。 A: SELECT S B: FORM SC WHERE C C: ='C2' AND GRAD>=<br>(SELECT GRADE FORM SC<br>WHERE C D: ='C2') E: SELECT S F: FORM SC<br>WHERE C G: ='C2' AND GRADE IN<br>(SELECT GRADE FORM SC<br>WHERE C H: ='C2') I: SELECT S J: FORM SC<br>WHERE C K: ='C2' AND GRADE NOT IN<br>(SELECT GRADE FORM SC<br>WHERE C L: ='C2') M: SELECT S N: FORM SC<br>WHERE C O: ='C2' AND GRADE>=ALL<br>(SELECT GRADE FORM SC<br>WHERE C P: ='C2')