设有关系模式:student(sno,sname,age,dept),现利用命令:CREATE VIEW stu AS SELECT*FROM student
设有关系模式:student(sno,sname,age,dept),现利用命令:
CREATE VIEW stu AS SELECT*FROM studentWHERE dept=cs
WITH CHECK OPTION
创建一个视图。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”)