• 2022-05-29
    有如下的SQL语句: Ⅰ.SELECT sname FROM s, sc WHERE grade<60 Ⅱ.SELECT sname FROM s WHERE sno IN(SELECT sno FROM sc WHERE grade<60) Ⅲ.SELECT sname FROM s, sc WHERE s.sno=sc.sno AND grade<60 若要查找分数(grade)不及格的学生姓名(sname),则以上正确的有哪些?( )
    A: Ⅰ和Ⅱ

    B: Ⅰ和Ⅲ

    C: Ⅱ和Ⅲ

    D: Ⅰ、Ⅱ和Ⅲ
  • 举一反三