假定学生关系是S(S#,SN,SEX,AGE),课程关系是C(C#,CN),学生选课关系是SC(S#,C#,GRADE)。其中:S#为,SN为姓名,SEX为性别,AGE为年龄,C#为课程号,CN为课程名,GRADE为成绩。下列(1)~(3)题均基于该关系模式。(1)检索所有比“”年龄大的学生姓名、年龄和性别。正确的SELECT语句是( )。
A.
SELECT SN,AGE,SEX FROM S WHERE AGE>(SELECT AGE FROM S WHERE SN='');
B.
SELECT SN,AGE,SEX FROM S WHERE SN=“';
C.
SELECT SN,AGE,SEX FROM S WHERE AGE>(SELECT AGE WHERE SN='');
D.
SELECT SN,AGE,SEX FROM S WHERE AGE>.AGE;