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1、视图 视图就是对select语句的封装 视图可以理解为一张只读的表,针对视图只能用select,不能用delete和update 创建一个视图,查询所有男生信息CREATE VIEW stu_nan as SELECT * from students where sex = '男';使用视图SELECT * from stu_nan INNER JOIN scores on stu_nan.studentNo = scores.studentNo;删除视图dro