ALTER VIEW

语法说明

ALTER VIEW 用于更改已存在的视图。

如果语法参数列表中命名的任何视图都不存在，语句报错，无法更改哪些不存在的视图。

语法结构

1. > ALTER VIEW view_name [(column_list)]
2. AS select_statement
3. [WITH [CASCADED | LOCAL] CHECK OPTION]

示例

1. drop table if exists t1;
2. create table t1 (a int);
3. insert into t1 values(1),(2),(3),(4);
4. create view v5 as select * from t1;

6. mysql> select * from v5;
7. +------+
8. | a    |
9. +------+
10. |    1 |
11. |    2 |
12. |    3 |
13. |    4 |
14. +------+
15. 4 rows in set (0.01 sec)

17. alter view v5 as select * from t1 where a=1;

19. mysql> select * from v5;
20. +------+
21. | a    |
22. +------+
23. |    1 |
24. +------+
25. 1 row in set (0.01 sec)

27. alter view v5 as select * from t1 where a > 2;

29. mysql> select * from v5;
30. +------+
31. | a    |
32. +------+
33. |    3 |
34. |    4 |
35. +------+
36. 2 rows in set (0.00 sec)