PHP uses mysql database to store session_PHP tutorial

Most people who use PHP will use cookies once they are applied to sessions.
Although cookies are good, they can also bring us some hidden dangers.
Hidden danger 1: If the cookie of the client machine becomes invalid due to a virus, then the session is equivalent to being gone.
Hidden danger 2: The session is saved in a temporary folder in the form of a file by default in PHP. For a small system, this is perfectly fine,
But for a large and frequently accessed system, this is not a good solution. Suppose this website is visited by 1,000 people a day. After one month, the temporary folder of the session will have 30,000 temporary files. Imagine how long it takes for the computer to find a session_sid from 30000!
So in order to improve efficiency.
The transaction uses a database to save the session. The specific method is as follows:
1. Change the php.ini file.
Since the default way of saving sessions in PHP is files, we need to change it. That is: find "session.save_handler = files" and change "files" to "User".
Change the session mode to user-defined.
2. Create a database:
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;
Database shows: db_session
Column name: sesskey, expiry, value Where: sesskey is the primary key.
Value stores the value in the session.
3. Create the session_mysql.php file. This file is used to construct a method to save the session. Just modify the parameters and use it directly.
session_mysql.php

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PHP code:

​​​​ $gb_DBname="db_myBBS";//Database name
         $gb_DBuser="root";//Database user name
​​​ $gb_DBpass="23928484";//Database password
         $gb_DBHOSTname="localhost";//The name or IP address of the host
                         
        $SESS_DBH="";
​​ ​ $SESS_LIFE=get_cfg_var("session.gc_maxlifetime");//Get the maximum validity period of the session.
                         
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();
    &n

http://www.bkjia.com/PHPjc/508429.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/508429.htmlTechArticle大部分使用php的人一旦应用到session都会使用cookie。 cookie虽好可是它也会给我们带来一些隐患的。 隐患一：如果客户端机器的cookie一旦因病...