写一段常用sql语句存储起来相当于多表的查询连接->形成的“新表”但视图不占存储空间，不存储数据
新建视图TeacherAndStudent之后可以select * from TeacherAndStudent也可以与其他表、视图再连接
SQL CREATE VIEW 语法
CREATE VIEW view_name AS
SELECT column_name(s) FROM table_name WHERE condition
转载于:https://www.cnblogs.com/Lulus/p/7874396.html
