Federated MySQL storage engine

8. Engine

mysql> show engines;
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
| Engine             | Support | Comment                                                        | Transactions | XA   | Savepoints |
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
| FEDERATED          | NO      | Federated MySQL storage engine                                 | NULL         | NULL | NULL       |
| MRG_MYISAM         | YES     | Collection of identical MyISAM tables                          | NO           | NO   | NO         |
| MyISAM             | YES     | MyISAM storage engine                                          | NO           | NO   | NO         |
| BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears) | NO           | NO   | NO         |
| MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables      | NO           | NO   | NO         |
| CSV                | YES     | CSV storage engine                                             | NO           | NO   | NO         |
| ARCHIVE            | YES     | Archive storage engine                                         | NO           | NO   | NO         |
| PERFORMANCE_SCHEMA | YES     | Performance Schema                                             | NO           | NO   | NO         |
| InnoDB             | DEFAULT | Supports transactions, row-level locking, and foreign keys     | YES          | YES  | YES        |
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
9 rows in set (0.00 sec)

8.1. FEDERATED

启用 FEDERATED 引擎, 服务器环境 Ubuntu 13.04

$ sudo vim /etc/mysql/conf.d/federated.cnf
[mysqld]
federated

$ sudo service mysql restart
		

mysql> show engines;
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
| Engine             | Support | Comment                                                        | Transactions | XA   | Savepoints |
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
| FEDERATED          | YES     | Federated MySQL storage engine                                 | NO           | NO   | NO         |
| MRG_MYISAM         | YES     | Collection of identical MyISAM tables                          | NO           | NO   | NO         |
| MyISAM             | YES     | MyISAM storage engine                                          | NO           | NO   | NO         |
| BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears) | NO           | NO   | NO         |
| MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables      | NO           | NO   | NO         |
| CSV                | YES     | CSV storage engine                                             | NO           | NO   | NO         |
| ARCHIVE            | YES     | Archive storage engine                                         | NO           | NO   | NO         |
| PERFORMANCE_SCHEMA | YES     | Performance Schema                                             | NO           | NO   | NO         |
| InnoDB             | DEFAULT | Supports transactions, row-level locking, and foreign keys     | YES          | YES  | YES        |
+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+
9 rows in set (0.00 sec)

A 服务器

CREATE TABLE `t1` (
	`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
	`name` VARCHAR(50) NOT NULL,
	`sex` ENUM('Y','N') NULL DEFAULT 'Y',
	`passwd` VARCHAR(50) NULL DEFAULT NULL,
	`ctime` TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
	`mtime` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
	PRIMARY KEY (`id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB
AUTO_INCREMENT=4;
		

B 服务器

DROP TABLE `users`;

CREATE TABLE `users` (
	`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
	`name` VARCHAR(50) NOT NULL,
	`sex` ENUM('Y','N') NULL DEFAULT 'Y',
	`ctime` TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
	`mtime` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
	PRIMARY KEY (`id`)
) ENGINE=FEDERATED connection = 'mysql://www:qwer123@192.168.2.1:3306/test/t1';
		

上面字段描述是你需要的字段，并非所有字段。这里屏蔽了passwd字段

提示

connection = 'MySQL://用户名:密码@主机:端口/数据库/表名'

mysql> DROP TABLE `users`;
Query OK, 0 rows affected (0.00 sec)

mysql> CREATE TABLE `users` (
    -> `id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
    -> `name` VARCHAR(50) NOT NULL,
    -> `sex` ENUM('Y','N') NULL DEFAULT 'Y',
    -> `ctime` TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
    -> `mtime` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    -> PRIMARY KEY (`id`)
    -> ) ENGINE=FEDERATED connection = 'mysql://www:qwer123@192.168.2.1:3306/test/t1';
Query OK, 0 rows affected (0.06 sec)

mysql>
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| users          |
+----------------+
1 row in set (0.00 sec)

mysql> desc users;
+-------+------------------+------+-----+---------------------+-----------------------------+
| Field | Type             | Null | Key | Default             | Extra                       |
+-------+------------------+------+-----+---------------------+-----------------------------+
| id    | int(10) unsigned | NO   | PRI | NULL                | auto_increment              |
| name  | varchar(50)      | NO   |     | NULL                |                             |
| sex   | enum('Y','N')    | YES  |     | Y                   |                             |
| ctime | timestamp        | NO   |     | 0000-00-00 00:00:00 |                             |
| mtime | timestamp        | NO   |     | CURRENT_TIMESTAMP   | on update CURRENT_TIMESTAMP |
+-------+------------------+------+-----+---------------------+-----------------------------+
5 rows in set (0.00 sec)

mysql> select * from users;
+----+------+------+---------------------+---------------------+
| id | name | sex  | ctime               | mtime               |
+----+------+------+---------------------+---------------------+
|  1 | neo  | Y    | 0000-00-00 00:00:00 | 2013-05-17 18:05:09 |
|  2 | zen  | Y    | 0000-00-00 00:00:00 | 2013-05-17 18:05:11 |
|  3 | lily | N    | 0000-00-00 00:00:00 | 2013-05-17 18:05:22 |
+----+------+------+---------------------+---------------------+
3 rows in set (0.01 sec)