mysql视图

mysql视图

1. 视图可以叫sql语句更简单

2. 保护数据给不同的人看不同的数据

create view view_table  as select *from table_name;

creaate view stu asselect a.name,a.age,a.email,a.phone,b.phpc,b.javac,b.oraclec from student a,score b where a.id=b.sid;

create [or replace] [algorithm={merge|temptable|undefined}]

view view_name [(column_list)]

as select_statement

[with [cascaded|local] check option]

视图有三种类型

Merge:会将引用视图的语句的文本与视图定义结合起来，使用得视图定义的某一部分取代语句对应部分

Temptable

undefined 没有指定默认 merge

algorithm=merge

with local check option   with[local]只要满足本视图的条件就可以更新

with cascaded check option  with [cascaded]必须满足所有针对视图的条件，才可以跟新

操作视图

alter view student_view as select *from student

drop view stu..,视图

show table status like 'stu2'/G'

show create view stu/G