教你使用MySQL觸發器自動更新memcache

mysql 5.1支持觸發器以及自定義函數接口(UDF)的特性，如果配合libmemcache以及Memcached Functions for MySQL，就能夠實現memcache的自動更新。簡單記錄一下安裝測試步驟。


安裝步驟

安裝memcached,這個步驟很簡單，隨處可見

安裝mysql server 5.1RC，安裝辦法也很大眾，不廢話了

編譯libmemcached，解壓后安裝即可./configure; make; make install

編譯Memcached Functions for MySQL，在http://download.tangent.org/找一個最新的版本下載就是，./configure --with-mysql=/usr/local/mysql/bin/mysql_config --libdir=/usr/local/mysql/lib/mysql/

make

make install

接下來有兩個辦法讓Memcached Functions for MySQL在mysql中生效

在mysql的shell中執行memcached_functions_mysql源碼目錄下的sql/install_functions.sql，這會把memcache function作為UDF加入mysql

運行memcached_functions_mysql源碼目錄下的utils/install.pl，這是一個perl腳本，作用同上一條

測試memcache function

以下測試腳本摘自memcached_functions_mysql的源碼目錄，有興趣可以試試


PLAIN TEXTCODE: drop table if exists urls;

create table urls (

id int(3) not null,

url varchar(64) not null default '',

primary key (id)

);


select memc_servers_set('localhost:11211');

select memc_set('urls:sequence', 0);


DELIMITER |


DROP TRIGGER IF EXISTS url_mem_insert;

CREATE TRIGGER url_mem_insert

BEFORE INSERT ON urls

FOR EACH ROW BEGIN

SET NEW.id= memc_increment('urls:sequence');

SET @mm= memc_set(concat('urls:',NEW.id), NEW.url);

END |


DELIMITER ;


insert into urls (url) values ('http://google.com');

insert into urls (url) values ('http://www.ooso.net/index.php');

insert into urls (url) values ('http://www.ooso.net/');

insert into urls (url) values ('http://slashdot.org');

insert into urls (url) values ('http://mysql.com');

select * from urls;


select memc_get('urls:1');

select memc_get('urls:2');

select memc_get('urls:3');

select memc_get('urls:4');

select memc_get('urls:5');