单项选择题
A.两个关系的交 B.两个关系的并 C.两个关系的积 D.两个关系的差
A.属于第一范式 B.属于第二范式 C.具有函数依赖关系 D.具有非函数依赖关系
A.SELECT TOP 4 WITH TIES * FROM Student ORDER BY Sage ASC B.SELECT TOP 4 WITH TIES * FROM Student GROUP BY Sage ASC C.SELECT TOP 4 WITH TIES * FROM Student ORDER BY Sage DESC D.SELECT TOP 4 WITH TIES * FROM Student GROUP BY Sage DESC