Mysql查询视图:ERROR 1449 (HY000)解决办法
问题重现
前几天因为有人删除了数据库中的记录,今天关闭了数据库的远程访问功能,今天接到开发报告,说出现 The user specified as a definer (‘air’@'%’) does not exist错误,他们定位是一张视图不能访问。利用实验重现了他们的情况
原因分析
因为创建视图使用的是xff@%用户(目前已经不存在),然后登录用户使用的是xff@localhost用户,导致mysql认为现在的用户无权限访问该视图,解决方法就是在当前用户下重建该视图
我使用的代码
代码如下 |
复制代码 |
[root@ECP-UC-DB1 ~]# mysql -uxff -pxifenfei
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 8846
Server version: 5.5.14-log MySQL Community Server (GPL)
Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
mysql> select user,host from mysql.user;
+------+---------------+
| user | host |
+------+---------------+
| xff | % |
| root | 127.0.0.1 |
| repl | 192.168.11.10 |
| root | ::1 |
| | ECP-UC-DB1 |
| root | ECP-UC-DB1 |
| root | localhost |
+------+---------------+
7 rows in set (0.08 sec)
mysql> use xifenfei;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> create view v_users as select * from wp_users;
Query OK, 0 rows affected (0.14 sec)
mysql> select count(*) from xifenfei.v_users;
+----------+
| count(*) |
+----------+
| 2 |
+----------+
1 row in set (0.03 sec)
mysql> update mysql.user set host='localhost' where user='xff' and host='%';
Query OK, 1 row affected (0.05 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.12 sec)
mysql> exit
Bye
[root@ECP-UC-DB1 ~]# mysql -uxff -pxifenfei
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 8847
Server version: 5.5.14-log MySQL Community Server (GPL)
Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
mysql> use xff;
ERROR 1049 (42000): Unknown database 'xff'
mysql> use xifenfei;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from v_users ;
ERROR 1449 (HY000): The user specified as a definer ('xff'@'%') does not exist
|
2、解决方法
代码如下 |
复制代码 |
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
| xifenfei |
+--------------------+
5 rows in set (0.00 sec)
mysql> use information_schema;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> desc VIEWS;
+----------------------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG | varchar(512) | NO | | | |
| TABLE_SCHEMA | varchar(64) | NO | | | |
| TABLE_NAME | varchar(64) | NO | | | |
| VIEW_DEFINITION | longtext | NO | | NULL | |
| CHECK_OPTION | varchar(8) | NO | | | |
| IS_UPDATABLE | varchar(3) | NO | | | |
| DEFINER | varchar(77) | NO | | | |
| SECURITY_TYPE | varchar(7) | NO | | | |
| CHARACTER_SET_CLIENT | varchar(32) | NO | | | |
| COLLATION_CONNECTION | varchar(32) | NO | | | |
+----------------------+--------------+------+-----+---------+-------+
10 rows in set (0.02 sec)
mysql> select TABLE_SCHEMA,TABLE_NAME,DEFINER from views;
+--------------+------------+---------+
| TABLE_SCHEMA | TABLE_NAME | DEFINER |
+--------------+------------+---------+
| xifenfei | v_users | xff@% |
+--------------+------------+---------+
1 row in set (0.16 sec)
mysql> create or replace view v_users as select * from wp_users;
ERROR 1044 (42000): Access denied for user 'xff'@'localhost' to database 'information_schema'
mysql> create or replace view xifenfei.v_users as select * from xifenfei.wp_users;
Query OK, 0 rows affected (0.02 sec)
mysql> select TABLE_SCHEMA,TABLE_NAME,DEFINER from views;
+--------------+------------+---------------+
| TABLE_SCHEMA | TABLE_NAME | DEFINER |
+--------------+------------+---------------+
| xifenfei | v_users | xff@localhost |
+--------------+------------+---------------+
1 row in set (0.01 sec)
mysql> select count(*) from xifenfei.v_users;
+----------+
| count(*) |
+----------+
| 2 |
+----------+
1 row in set (0.03 sec)
|
1.注意事项
创建视图存在如下注意事项:
(1) 运行创建视图的语句需要用户具有创建视图(CRATE VIEW)的权限,若加了[OR REPLACE]时,还需要用户具有删除视图(DROP VIEW)的权限;
(2) SELECT语句不能包含FROM子句中的子查询;
(3) SELECT语句不能引用系统或用户变量;
(4) SELECT语句不能引用预处理语句参数;
(5) 在存储子程序内,定义不能引用子程序参数或局部变量;
(6) 在定义中引用的表或视图必须存在。但是,创建了视图后,能够舍弃定义引用的表或视图。要想检查视图定义是否存在这类问题,可使用CHECK TABLE语句;
(7) 在定义中不能引用TEMPORARY表,不能创建TEMPORARY视图;
(8) 在视图定义中命名的表必须已存在;
(9) 不能将触发程序与视图关联在一起;
(10) 在视图定义中允许使用ORDER BY,但是,如果从特定视图进行了选择,而该视图使用了具有自己ORDER BY的语句,它将被忽略。
补充一下mysql视图基本知识
创建视图——CREATE VIEW
1.语法
代码如下 |
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CREATE [OR REPLACE] [ALGORITHM = {UNDEFINED | MERGE | TEMPTABLE}] VIEW [db_name.]view_name [(column_list)] AS select_statement [WITH [CASCADED | LOCAL] CHECK OPTION] |
通过该语句可以创建视图,若给定了[OR REPLACE],则表示当已具有同名的视图时,将覆盖原视图。select_statement是一个查询语句,这个查询语句可从表或其它的视图中查询。视图属于数据库,因此需要指定数据库的名称,若未指定时,表示在当前的数据库创建新视图。
表和数据库共享数据库中相同的名称空间,因此,数据库不能包含相同名称的表和视图,并且,视图的列名也不能重复。
1.使用举例
Eg. 本例创建一个产品表(product)和一个购买记录表(purchase),再通过视图purchase_detail查询出购买的详细信息。
代码如下 |
复制代码 |
CREATE TABLE product
(
product_id INT NOT NULL,
name VARCHAR(50) NOT NULL,
price DOUBLE NOT NULL
);
INSERT INTO product VALUES(1, 'apple ', 5.5);
CREATE TABLE purchase
(
id INT NOT NULL,
product_id INT NOT NULL,
qty INT NOT NULL DEFAULT 0,
gen_time DATETIME NOT NULL
);
INSERT INTO purchase VALUES(1, 1, 10, NOW());
CREATE VIEW purchase_detail AS SELECT product.name as name, product .price as price, purchase.qty as qty, product .price * purchase.qty as total_value from product, purchase where product.product_id = purchase.product_id; |
创建成功后,输入:SELECT * FROM purchase_detail;
运行效果如下:
代码如下 |
复制代码 |
+-------+-------+-----+-------------+
| name | price | qty | total_value |
+-------+-------+-----+-------------+
| apple | 5.5 | 10 | 55 |
+-------+-------+-----+-------------+
1 row in set (0.01 sec)
|
补充:数据库,mysql教程