设有关系模式:student (sno,sname,age,dept),现利用命令:CREATE VIEW stu AS SELECT*FROM studen
设有关系模式:student (sno,sname,age,dept),现利用命令: CREATE VIEW stu AS SELECT*FROM student WHERE dept="cs"WITH CHECK OPTION 创建了一个视图。则以下SQL命令中能正确执行的是()。
A.UPDATE stu SET dept="maths"
B.UPDATE stu SET dept="maths" WHERE age>=20
C.INSERT INTO stu VALUES("2004001","John",30,"cs")
D.INSERT INTO stu VALUES("2004001","John",50,"maths")