Mysql 开启Federated引擎的方法

YES支持并开启

DEFAULT支持并开启, 并且为默认引擎

NO不支持

DISABLED支持,但未开启

参考一下在windows下的解决办法，在my.cnf中增加一行

复制代码 代码如下:

federated

1. 查看当前支持的存储引擎

SQL>show engines;

复制代码 代码如下:

+------------+---------+------------------------------------------------------------+--------------+------+------------+
| Engine| Support | Comment| Transactions | XA | Savepoints |
+------------+---------+------------------------------------------------------------+--------------+------+------------+
| CSV| YES| CSV storage engine| NO| NO | NO|
| MRG_MYISAM | YES| Collection of identical MyISAM tables| NO| NO | NO|
| MEMORY| YES| Hash based, stored in memory, useful for temporary tables | NO| NO | NO|
| InnoDB| DEFAULT | Supports transactions, row-level locking, and foreign keys | YES| YES | YES|
| MyISAM| YES| Default engine as of MySQL 3.23 with great performance| NO| NO | NO|
+------------+---------+------------------------------------------------------------+--------------+------+------------+
5 rows in set (0.00 sec)

2. 安装federated存储引擎

由于编译时没有选择federated，所以打算通过INSTALL PLUGIN的方式安装，正常情况下，federated是支持动态安装的：
=== Federated Storage Engine ===
Plugin Name:federated
Description:Connects to tables on remote MySQL servers
Supports build: static and dynamic
Configurations: max, max-no-ndb

可是执行以下命令时报错：

SQL>install plugin federated soname 'ha_federated.so';
ERROR 1126 (HY000): Can't open shared library '/usr/local/mysql/lib/mysql/plugin/ha_federated.so' (errno: 2 undefined symbol: dynstr_append_mem)
搜了一下，发现是个老问题，竟然到现在都没解决，可见MySQL团队的效率和管理的混乱。?id=40942
没有办法了，只有重新编译MySQL源码了, 加上--with-plugins=federated。从5.1.26开始，默认MySQL不启用federated存储引擎，所以需要在my.cnf中加入federated选项或是在命令行用--federated选项启动mysqld。编译后的结果如下：

SQL>show engines;

复制代码 代码如下:

+------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
| Engine| Support | Comment| Transactions | XA | Savepoints |
+------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
| CSV| YES| CSV storage engine| NO| NO | NO|
| MRG_MYISAM | YES| Collection of identical MyISAM tables| NO| NO | NO|
| FEDERATED | YES| Federated MySQL storage engine| NO| NO | NO|
| MyISAM| YES| Default engine as of MySQL 3.23 with great performance| NO| NO | NO|
| InnoDB| DEFAULT | Percona-XtraDB, 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|
+------------+---------+----------------------------------------------------------------------------+--------------+------+------------+
6 rows in set (0.00 sec)