题目
A.SC.成绩>=’B’
B.SC.成绩<=’B’
C.SC.成绩≤’B’
D.SC.成绩!<’B’
第1题
A.课号,成绩
B.学号,成绩
C.学号,课号
D.学号,姓名,成绩
第2题
第3题
第4题
A.SELECT S# FROM SC WHERE C#='C2' AND GRADE >= ALL(SELECT GRADE FROM SC WHERE C#='C2')
B.SELECT S# FROM SC WHERE C#='C2' AND GRADE >=(SELECT GRADE FROM SC WHERE C#='C2')
C.SELECT S# FROM SC WHERE C#='C2' AND GRADE IN (SELECT GRADE FROM SC WHERE C#='C2')
D.SELECT S# FROM SC WHERE C#='C2' AND GRADE NOT IN(SELECT GRADE FROM SC WHERE C#='C2')
第5题
A.SELECT S# FROM SC WHERE C#=C2 AND GRADE>=(SELECT GRADE FROM SC WHERE C#=C2)
B.SELECT S# FROM SC WHERE C#=C2 AND GRADE IN(SELECT GRADE FROM SC WHERE C#=C2)
C.SELECT S# FROM SC WHERE C#=C2 AND GRADE NOT IN (SELECT GRADE GORM SC WHERE C#=C2)
D.SELECT S# FROM SC WHERE C#=C2 AND GRADE>=ALL(SELECT GRADE FROM SC WHERE C#=C2)
第6题
A.SELECT S# FROM SC WHERE C#='C2' AND GRADE >= ALL(SELECT GRADE FROM SC WHERE C#='C2')
B.SELECT S# FROM SC WHERE C#='C2' AND GRADE >=(SELECT GRADE FROM SC WHERE C#='C2')
C.SELECT S# FROM SC WHERE C#='C2' AND GRADE IN (SELECT GRADE FROM SC WHERE C#='C2')
D.SELECT S# FROM SC WHERE C#='C2' AND GRADE NOT IN(SELECT GRADE FROM SC WHERE C#='C2')
第7题
A.π学号,成绩(σ课程号='C02'∨课程号='C04'(选课))
B.π学号,成绩(σ课程号='C02'(选课))∪π学号,成绩(σ课程号='C04'(选课))
C.π学号,成绩((σ课程号='C02'(选课))∪(σ课程号='C04'(选课)))
D.π学号,成绩(σ课程号='C02'∨'C04'(选课))
第8题
A.π学号,成绩(σ课程号='C02'∨课程号='C04'(选课))
B.π学号,成绩(σ课程号='C02'(选课))∪π学号,成绩(σ课程号='C04'(选课))
C.π学号,成绩((σ课程号='C02'(选课))∪(σ课程号='C04'(选课)))
D.π学号,成绩(σ课程号='C02'∨'C04'(选课))
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