MYSQL 链接远程的FEDERATED引擎链接表(类似ORACLE的DBLINK)

MYSQL 链接远程的链接表(类似ORACLE的DBLINK)关于链接表

远程表：CREATE TABLE IF NOTEXISTS `category` ( `id` int(11) NOTNULLAUTO_INCREMENT, `category_id`int(11) NOTNULL, `name`varchar(20) NOTNULL, PRIMARYKEY(`id`)
)ENGINE=MYSAIMDEFAULTCHARSET=utf8;

本地建立链接表（映射10.10.10.133 app库的category表）的时候：

CREATE TABLE IF NOT EXISTS `remotecategory` (

`id` int(11) NOT NULL AUTO_INCREMENT,

`category_id` int(11) NOT NULL,

`name` varchar(20) NOT NULL,

PRIMARY KEY (`id`)

)ENGINE=FEDERATED DEFAULT CHARSET=utf8

CONNECTION='mysql://user:passwod@10.10.10.133:3306/app/category'; 注：表的结构一模一样，就是引擎不同，看红字FEDERATED

需要在 my.ini 的 [mysqld] 下面 加上federated
来激活FEDERATED （mysql 5.0.5以上的版本）

show engines

查看是否安装FEDERATED引擎，没有的重新编译一下

cmake . -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DINSTALL_DATADIR=/opt/mnt/mydata -DDEFAULT_CHARSET=utf8

-DDEFAULT_COLLATION=utf8_general_ci -DEXTRA_CHARSETS=all -DWIT

H_SSL=system -DWITH_EMBEDDED_SERVER=1 -DENABLED_LOCAL_INFILE=1 -DWITH_MYISAM_STORAGE_ENGINE=1

-DWITH_PERFSCHEMA_STORAGE_ENGINE=1

---------------------------------------------------------------------------------------------------------------

mysql> show engines;

+--------------------+---------+------------------------------------------------------------+--------------+------+------------+

| Engine | Support | Comment | Transactions | XA | Savepoints |

+--------------------+---------+------------------------------------------------------------+--------------+------+------------+

| PERFORMANCE_SCHEMA | YES | Performance Schema | NO | NO | NO |

| FEDERATED | NO | Federated MySQL storage engine | NULL | NULL | NULL |

| CSV | YES | CSV storage engine | NO | NO | NO |

| MRG_MYISAM | YES | Collection of identical MyISAM tables | NO | NO | NO |

| MyISAM | YES | MyISAM storage engine | NO | NO | NO |

| InnoDB | DEFAULT | Supports transactions, row-level locking, and foreign keys | YES | YES | YES |

| MEMORY | YES | Hash based, stored in memory, useful for temporary tables | NO | NO | NO |

+--------------------+---------+------------------------------------------------------------+--------------+------+------------+

7 rows in set (0.00 sec)

mysql> show plugins;

+-----------------------+----------+--------------------+--------------------+---------+

| Name | Status | Type | Library | License |

+-----------------------+----------+--------------------+--------------------+---------+

| binlog | ACTIVE | STORAGE ENGINE | NULL | GPL |

| mysql_native_password | ACTIVE | AUTHENTICATION | NULL | GPL |

| mysql_old_password | ACTIVE | AUTHENTICATION | NULL | GPL |

| MEMORY | ACTIVE | STORAGE ENGINE | NULL | GPL |

| CSV | ACTIVE | STORAGE ENGINE | NULL | GPL |

| MRG_MYISAM | ACTIVE | STORAGE ENGINE | NULL | GPL |

| MyISAM | ACTIVE | STORAGE ENGINE | NULL | GPL |

| PERFORMANCE_SCHEMA | ACTIVE | STORAGE ENGINE | NULL | GPL |

| InnoDB | ACTIVE | STORAGE ENGINE | NULL | GPL |

| INNODB_TRX | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| INNODB_LOCKS | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| INNODB_LOCK_WAITS | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| INNODB_CMP | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| INNODB_CMP_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| INNODB_CMPMEM | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| INNODB_CMPMEM_RESET | ACTIVE | INFORMATION SCHEMA | NULL | GPL |

| FEDERATED | DISABLED | STORAGE ENGINE | NULL | GPL |

| partition | ACTIVE | STORAGE ENGINE | NULL | GPL |

| rpl_semi_sync_master | ACTIVE | REPLICATION | semisync_master.so | GPL |

| rpl_semi_sync_slave | ACTIVE | REPLICATION | semisync_slave.so | GPL |

+-----------------------+----------+--------------------+--------------------+---------+

20 rows in set (0.01 sec)

vim /etc/my.cnf

添加一行

federated

既可

------------------------------------------------------------------------------------------------------

federated远程连接表对主从有影响

主：

mysql> select * from lijiwei_48;

Empty set (0.00 sec)

mysql>

从：

mysql> select * from lijiwei_48;

Empty set (0.00 sec)

mysql>

主：

mysql> insert into lijiwei_48 values(1);

Query OK, 1 row affected (0.01 sec)

mysql> select * from lijiwei_48;

+------+

| id |

+------+

| 1 |

| 1 |

+------+

2 rows in set (0.00 sec)

从：

mysql> select * from lijiwei_48;

+------+

| id |

+------+

| 1 |

| 1 |

+------+

2 rows in set (0.00 sec)

主从两台mysql各自插入一条数据，导致同步数据出错

同步dblink类似数据库要格外小心，同样当心触发器

使用FEDERATED建表语句如下：

CREATE TABLE (......) ENGINE =FEDERATED CONNECTION='mysql://[name]:[pass]@[location]:[port]/[db-name]/[table-name]'

创建成功后就可直接在本地查询相应的远程表了。

需要注意的几点：

1. 本地的表结构必须与远程的完全一样。

2.远程数据库目前仅限MySQL

3.不支持事务

4.不支持表结构修改