现要查找缺少成绩(Grade)的学生学号(Snum),相应的SQL语句是( )A.SELECT Snum FROM SC WHERE Grade IS NULLB.SELECT Snum FROM SC WHERE Grade
现要查找缺少成绩(Grade)的学生学号(Snum),相应的SQL语句是( )
A、SELECT Snum FROM SC WHERE Grade IS NULL
B、SELECT Snum FROM SC WHERE Grade
发布时间：2024-10-17 19:33:08
