查询student表中的所有非空email信息，以下语句正确的是（）。A、Select email from student where email !=nullB、Select email from student where email not is nullC、Select email from student where email <> nullD、Select email from student where email is not null

更多“查询student表中的所有非空email信息，以下语句正确的是（）。A、Select email from student where email !=nullB、Select email from student where email not is nullC、Select email from student where email nullD、Select email from student where email is not null”相关问题