用mysql触发器自动更新memcache

 

mysql 5.1支持触发器以及自定义函数接口(UDF)的特性，如果配合libmemcache以及Memcached Functions for MySQL，就能够实现memcache的自动更新。简单记录一下安装测试步骤。

安装步骤

• 安装memcached,这个步骤很简单，随处可见
• 安装mysql server 5.1RC，安装办法也很大众，不废话了
• 编译libmemcached，解压后安装即可./configure; make; make install
• 编译Memcached Functions for MySQL，在http://download.tangent.org/找一个最新的版本下载就是，./configure --with-mysql=/usr/local/mysql/bin/mysql_config --libdir=/usr/local/mysql/lib/mysql/
make
make install
• 接下来有两个办法让Memcached Functions for MySQL在mysql中生效
  • 在mysql的shell中执行memcached_functions_mysql源码目录下的sql/install_functions.sql，这会把memcache function作为UDF加入mysql
  • 运行memcached_functions_mysql源码目录下的utils/install.pl，这是一个perl脚本，作用同上一条

测试memcache function

以下测试脚本摘自memcached_functions_mysql的源码目录，有兴趣可以试试

PLAIN TEXT

CODE:

1. drop table if exists urls;
2. create table urls (
3.   id int ( 3 ) not null,
4.   url varchar ( 64 ) not null default '',
5.   primary key (id )
6.   );
7.  
8. select memc_servers_set ( 'localhost:11211' );
9. select memc_set ( 'urls:sequence', 0 );
10.  
11. DELIMITER |
12.  
13. DROP TRIGGER IF EXISTS url_mem_insert;
14. CREATE TRIGGER url_mem_insert
15. BEFORE INSERT ON urls
16. FOR EACH ROW BEGIN
17.     SET NEW. id= memc_increment ( 'urls:sequence' );
18.     SET @mm= memc_set (concat ( 'urls:',NEW. id ), NEW. url );
19. END |
20.  
21. DELIMITER ;
22.  
23. insert into urls (url ) values ( 'http://google.com' );
24. insert into urls (url ) values ( 'http://www.ooso.net/index.php' );
25. insert into urls (url ) values ( 'http://www.ooso.net/' );
26. insert into urls (url ) values ( 'http://slashdot.org' );
27. insert into urls (url ) values ( 'http://mysql.com' );
28. select * from urls;
29.  
30. select memc_get ( 'urls:1' );
31. select memc_get ( 'urls:2' );
32. select memc_get ( 'urls:3' );
33. select memc_get ( 'urls:4' );
34. select memc_get ( 'urls:5' );