php使用mysql資料庫儲存session的例子

CREATE TABLE `db_session` (
`sesskey` char(32) NOT NULL,
`expiry` int(11) unsigned NOT NULL,
`value` text NOT NULL,
PRIMARY KEY (`sesskey`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

数据库表明：db_session 列名：sesskey，expiry，value　其中：sesskey为主键。 Value里面存放着session里面的值。

3.建立session_mysql.php文件。这个文件是用来构造保存session的方法的。修改一下参数直接使用就可以了。 session_mysql.php php代码:

$gb_DBname="db_myBBS";//数据库名称
$gb_DBuser="root";//数据库用户名称
$gb_DBpass="23928484";//数据库密码
$gb_DBHOSTname="localhost";//主机的名称或是IP地址
$SESS_DBH="";
$SESS_LIFE=get_cfg_var("session.gc_maxlifetime");//得到session的最大有效期。
function sess_open($save_path,$session_name){
global $gb_DBHOSTname,$gb_DBname,$gb_DBuser,$gb_DBpass,$SESS_DBH;
if(!$SESS_DBH=mysql_pconnect($gb_DBHOSTname,$gb_DBuser,$gb_DBpass)){
echo "
MySql Error:".mysql_error()."
";
die();
}
if(!mysql_select_db($gb_DBname,$SESS_DBH)){
echo "
MySql Error:".mysql_error()."
";
die();
}
return true;
}
function sess_close(){
return true;
}
function sess_read($key){
global $SESS_DBH,$SESS_LIFE;
$qry="select value from db_session where sesskey = '$key' and expiry > ".time();
$qid=mysql_query($qry,$SESS_DBH);
if(list($value)=mysql_fetch_row($qid)){
return $value;
}
return false;
}
function sess_write($key,$val){
global $SESS_DBH,$SESS_LIFE;
$expiry=time()+$SESS_LIFE;
$value=$val;
$qry="insert into db_session values('$key',$expiry,'$value')";
$qid=mysql_query($qry,$SESS_DBH);
if(!$qid){
$qry="update db_session set expiry=$expiry, value='$value' where sesskey='$key' and expiry >".time();
$qid=mysql_query($qry,$SESS_DBH);
}
return $qid;
}
function sess_destroy($key){
global $SESS_DBH;
$qry="delete from db_session where sesskey = '$key'";
$qid=mysql_query($qry,$SESS_DBH);
return $qid;
}
function sess_gc($maxlifetime){
global $SESS_DBH;
$qry="delete from db_session where expiry < ".time();
$qid=mysql_query($qry,$SESS_DBH);
return mysql_affected_rows($SESS_DBH);
}
session_module_name();
session_set_save_handler("sess_open","sess_close","sess_read","sess_write","sess_destroy","sess_gc");
?>

4.建立测试文件。 在使用之前必须引用刚刚建立的session_mysql.php文件。 文件：session_test.php

include ("session_mysql.php");
session_start();
$_SESSION['abc']= "A: I will be back!";
$_SESSION['meto']= "B: Me too ";
$_SESSION['name']= "louis ";
echo "click me";
?>

文件：get_session_test.php

include ("session_mysql.php");
session_start();
echo $_SESSION['abc'];
echo "";
echo $_SESSION['meto'];
echo "";
echo $_SESSION['name'];
$_SESSION['wq']="12e";
echo "click again";
?>

文件：get_session_test2.php

include ("session_mysql.php");
session_start();
echo $_SESSION['abc'];
echo "";
echo $_SESSION['meto'];
echo "";
echo $_SESSION['name'];
echo "";
echo $_SESSION['wq'];
//session_destroy();//用来销毁所有session的函数。
?>