MySQL中使用FREDATED引擎實現(xiàn)跨數(shù)據庫服務器、跨實例訪問

更新時間：2014年10月31日 09:54:58 作者：Leshami

這篇文章主要介紹了MySQL中使用FREDATED引擎實現(xiàn)跨數(shù)據庫服務器、跨實例訪問,本文講解了FEDERATED存儲引擎的描述、安裝與啟用FEDERATED存儲引擎、準備遠程服務器環(huán)境等內容,需要的朋友可以參考下

跨數(shù)據庫服務器，跨實例訪問是比較常見的一種訪問方式，在Oracle中可以通過DB LINK的方式來實現(xiàn)。對于MySQL而言，有一個FEDERATED存儲引擎與之相對應。同樣也是通過創(chuàng)建一個鏈接方式的形式來訪問遠程服務器上的數(shù)據。本文簡要描述了FEDERATED存儲引擎，以及演示了基于FEDERATED存儲引擎跨實例訪問的示例。

1、FEDERATED存儲引擎的描述

FEDERATED存儲引擎允許在不使用復制或集群技術的情況下實現(xiàn)遠程訪問數(shù)據庫
創(chuàng)建基于FEDERATED存儲引擎表的時候，服務器在數(shù)據庫目錄僅創(chuàng)建一個表定義文件，即以表名開頭的.frm文件。

FEDERATED存儲引擎表無任何數(shù)據存儲到本地，即沒有.myd文件
對于遠程服務器上表的操作與本地表操作一樣，僅僅是數(shù)據位于遠程服務器
基本流程如下：

2、安裝與啟用FEDERATED存儲引擎

源碼安裝MySQL時使用DWITH_FEDERATED_STORAGE_ENGINE來配置
rpm安裝方式缺省情況下已安裝，只需要啟用該功能即可

3、準備遠程服務器環(huán)境

復制代碼代碼如下:

-- 此演示中遠程服務器與本地服務器為同一服務器上的多版本多實例  

-- 假定遠程服務為：5.6.12(實例3406)  

-- 假定本地服務器：5.6.21(實例3306)     

-- 基于實例3306創(chuàng)建FEDERATED存儲引擎表test.federated_engine以到達訪問實例3406數(shù)據庫tempdb.tb_engine的目的  

[root@rhel64a ~]# cat /etc/issue  

Red Hat Enterprise Linux Server release 6.4 (Santiago)   

--啟動3406的實例  

[root@rhel64a ~]# /u01/app/mysql/bin/mysqld_multi start 3406  

[root@rhel64a ~]# mysql -uroot -pxxx -P3406 --protocol=tcp  

root@localhost[(none)]> show variables like 'server_id';  

+---------------+-------+  

| Variable_name | Value |  

+---------------+-------+  

| server_id     | 3406  |  

+---------------+-------+  

--實例3406的版本號  

root@localhost[tempdb]> show variables like 'version';  

+---------------+------------+  

| Variable_name | Value      |  

+---------------+------------+  

| version       | 5.6.12-log |  

+---------------+------------+  

--創(chuàng)建數(shù)據庫  

root@localhost[(none)]> create database tempdb;  

Query OK, 1 row affected (0.00 sec)  

-- Author : Leshami  

-- Blog   ：http://blog.csdn.net/leshami  

root@localhost[(none)]> use tempdb  

Database changed  

--創(chuàng)建用于訪問的表  

root@localhost[tempdb]> create table tb_engine as   

    -> select engine,support,comment from information_schema.engines;  

Query OK, 9 rows affected (0.10 sec)  

Records: 9  Duplicates: 0  Warnings: 0  

--提取表的SQL語句用于創(chuàng)建為FEDERATED存儲引擎表  

root@localhost[tempdb]> show create table tb_engine \G  

*************************** 1. row ***************************  

       Table: tb_engine  

Create Table: CREATE TABLE `tb_engine` (  

  `engine` varchar(64) NOT NULL DEFAULT '',  

  `support` varchar(8) NOT NULL DEFAULT '',  

  `comment` varchar(80) NOT NULL DEFAULT ''  

) ENGINE=InnoDB DEFAULT CHARSET=utf8  

--創(chuàng)建用于遠程訪問的賬戶  

root@localhost[tempdb]> grant all privileges on tempdb.* to 'remote_user'@'192.168.1.131' identified by 'xxx';  

Query OK, 0 rows affected (0.00 sec)  

root@localhost[tempdb]> flush privileges;  

Query OK, 0 rows affected (0.00 sec)

4、演示FEDERATED存儲引擎跨實例訪問

復制代碼代碼如下:

[root@rhel64a ~]# mysql -uroot -pxxx  

root@localhost[(none)]> show variables like 'version';  

+---------------+--------+  

| Variable_name | Value  |  

+---------------+--------+  

| version       | 5.6.21 |  

+---------------+--------+  

#查看是否支持FEDERATED引擎  

root@localhost[(none)]> select * from information_schema.engines where engine='federated';  

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

| ENGINE    | SUPPORT | COMMENT                        | TRANSACTIONS | XA   | SAVEPOINTS |  

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

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

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

root@localhost[(none)]> exit  

[root@rhel64a ~]# service mysql stop  

Shutting down MySQL..[  OK  ]  

#配置啟用FEDERATED引擎  

[root@rhel64a ~]# vi /etc/my.cnf  

[root@rhel64a ~]# tail -7 /etc/my.cnf  

[mysqld]  

socket = /tmp/mysql3306.sock  

port = 3306  

pid-file = /var/lib/mysql/my3306.pid  

user = mysql  

server-id=3306/  

federated         #添加該選項  

[root@rhel64a ~]# service mysql start  

Starting MySQL.[  OK  ]  

[root@rhel64a ~]# mysql -uroot -pxxx  

root@localhost[(none)]> select * from information_schema.engines where engine='federated';  

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

| ENGINE    | SUPPORT | COMMENT                        | TRANSACTIONS | XA   | SAVEPOINTS |  

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

| FEDERATED | YES     | Federated MySQL storage engine | NO           | NO   | NO         |  

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

root@localhost[(none)]> use test  

-- 創(chuàng)建基于FEDERATED引擎的表federated_engine  

root@localhost[test]> CREATE TABLE `federated_engine` (  

    ->   `engine` varchar(64) NOT NULL DEFAULT '',  

    ->   `support` varchar(8) NOT NULL DEFAULT '',  

    ->   `comment` varchar(80) NOT NULL DEFAULT ''  

    -> ) ENGINE=FEDERATED DEFAULT CHARSET=utf8  

    -> CONNECTION='mysql://remote_user:xxx@192.168.1.131:3406/tempdb/tb_engine';  

Query OK, 0 rows affected (0.00 sec)  

-- 下面是創(chuàng)建后表格式文件  

root@localhost[test]> system ls -hltr /var/lib/mysql/test  

total 12K  

-rw-rw---- 1 mysql mysql 8.5K Oct 24 08:22 federated_engine.frm  

--查詢表federated_engine  

root@localhost[test]> select * from federated_engine limit 2;  

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

| engine     | support | comment                               |  

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

| MRG_MYISAM | YES     | Collection of identical MyISAM tables |  

| CSV        | YES     | CSV storage engine                    |  

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

--更新表federated_engine  

root@localhost[test]> update federated_engine set support='NO' where engine='CSV';  

Query OK, 1 row affected (0.03 sec)  

Rows matched: 1  Changed: 1  Warnings: 0  

--查看更新后的結果  

root@localhost[test]> select * from federated_engine where engine='CSV';  

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

| engine | support | comment            |  

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

| CSV    | NO      | CSV storage engine |  

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

5、創(chuàng)建FEDERATED引擎表的鏈接方式

復制代碼代碼如下:

scheme://user_name[:password]@host_name[:port_num]/db_name/tbl_name

    scheme: A recognized connection protocol. Only mysql is supported as the scheme value at this point.

    user_name: The user name for the connection. This user must have been created on the remote server, and must have suitable privileges to perform the required actions (SELECT, INSERT,UPDATE, and so forth) on the remote table.

    password: (Optional) The corresponding password for user_name.

    host_name: The host name or IP address of the remote server.

    port_num: (Optional) The port number for the remote server. The default is 3306.

    db_name: The name of the database holding the remote table.

    tbl_name: The name of the remote table. The name of the local and the remote table do not have to match.

鏈接示例樣本:

    CONNECTION='mysql://username:password@hostname:port/database/tablename'

    CONNECTION='mysql://username@hostname/database/tablename'

    CONNECTION='mysql://username:password@hostname/database/tablename'