若查询考试成绩不为空的学生的学号,下列语句哪个是正确的?( )
A: SELECT Sno FROM SC WHERE Grade >= 0;
B: SELECT Sno FROM SC WHERE Grade != 0;
C: SELECT Sno FROM SC WHERE Grade IS NOT NULL;
D: SELECT Sno FROM SC WHERE Grade NOT IS NULL;
A: SELECT Sno FROM SC WHERE Grade >= 0;
B: SELECT Sno FROM SC WHERE Grade != 0;
C: SELECT Sno FROM SC WHERE Grade IS NOT NULL;
D: SELECT Sno FROM SC WHERE Grade NOT IS NULL;
举一反三
- 若查询考试成绩不为空的学生的学号,下列语句哪个是正确的? A: SELECT Sno FROM SC WHERE Grade >= 0; B: SELECT Sno FROM SC WHERE Grade!= 0; C: SELECT Sno FROM SC WHERE Grade NOT IS NULL; D: SELECT Sno FROM SC WHERE Grade IS NOT NULL;
- 查询所有有成绩的学生学号和课程号。正确的SELECT语句是()。 A: Select sno , cno from sc where grade < > null B: Select sno as 学号, cno as 课程号 from sc where grade is not null C: Select sno , cno from sc where grade !=‘ ’ D: Select sno , cno from sc where grade is not null
- 下列SQL语句中,________可以在“学生-课程”数据库中实现“查询所有有成绩的学生学号和课程号”。 A: SELECT Sno,Cno FROM SC WHERE Grade <> NULL B: SELECT Sno,Cno FROM SC WHERE Grade NOT NULL C: SELECT Sno,Cno FROM SC WHERE Grade >0 D: SELECT Sno,Cno FROM SC WHERE Grade IS NOT NULL
- “查询没有学习成绩的学生的学号和课程号”的SQL语 句是( ) (2.0) A: SELECT sno,cno FROM SC WHERE grade = NULL B: SELECT sno,cno FROM SC WHERE grade IS ' ' C: SELECT sno,cno FROM SC WHERE grade IS NULL D: SELECT sno,cno FROM SC WHERE grade = ' '
- 检索选修了课程”C1”的学生中成绩最高的学生的学号,正确的SELECT语句为( ) A: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE >=ALL (SELECT Grade FROM SC WHERE Cno=’C1’); B: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE IN (SELECT Grade FROM SC WHERE Cno=’C1’); C: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE > ANY (SELECT Grade FROM SC WHERE Cno=’C1’); D: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE >= (SELECT Grade FROM SC WHERE Cno=’C1’);