Save session in database How to save session in database-PHP Tutorial-php.cn

Save session in database How to save session in database

WBOY

Release： 2016-07-29 08:34:41

Original

1000 people have browsed it

PHP's session is saved as a file on the server side by default, and cookies are used to save variables on the client side. This will cause a problem. When a user turns off the browser's cookies due to some security reasons, the session-related operations in the program will not be executed. Therefore, if session data can be saved in a database, it will not be restricted by client settings, and there will be a leap in performance and scalability. The key function used in the program is session_set_save_handler, and session.save_handler = files in php.ini must be changed to user. The environment we are discussing here is linux(freesd)+apache+mysql+php.
Data table structure: [sessions]
CREATE TABLE sessions (
sesskey char(32) not null,
expiry int(11) unsigned not null,
value text not null,
PRIMARY KEY (sesskey)
);
Program code ：[session_inc.php]
$SESS_DBHOST = "yourhost"; /* database server hostname */
$SESS_DBNAME = "yourdb"; /* database name */
$SESS_DBUSER = "youruser"; /* database user */
$SESS_DBPASS = "yourpassword"; /* database password */
$SESS_DBH = "";
$SESS_LIFE = get_cfg_var("session.gc_maxlifetime");
function sess_open($save_path, $session_name) {
global $SESS_DBHOST, $SESS_DBNAME, $SESS_DBUSER, $SESS_DBPASS, $SESS_DBH;
if (! $SESS_DBH = mysql_pconnect($SESS_DBHOST, $SESS_DBUSER, $SESS_DBPASS)) {
echo "

Can't connect to $ SESS_DBHOST As $ sess_dbuser ";
echo" & lt; li & gt; mysql error: "." mysql_error ();
die;
}

((! MySQL_SELECT_DB ($ sess_dbname, $ sess_dbh)) & Echo "& lt; li & gt; unable to select database $SESS_DBNAME";
return true; ESS_LIFE;
$qry = "SELECT value FROM session_tbl WHERE sesskey = '$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; //Expiration time
$value = addslashes($val);
$qry = "INSERT INTO session_tbl VALUES ('$key', $expiry, '$value')";
$qid = mysql_query($qry, $SESS_DBH);
if (! $qid ) {
$qry = "UPDATE session_tbl 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;
$qry = "DELETE FROM session_tbl WHERE sesskey = '$key'";
$qid = mysql_que ry($qry, $ SESS_DBH);
return $qid;
}
function sess_gc($maxlifetime) {
global $SESS_DBH;
$qry = "DELETE FROM session_tbl WHERE expiry < " . time();
$qid = mysql_query ($qry, $SESS_DBH);
return mysql_affected_rows($SESS_DBH);
}
session_set_save_handler(
"sess_open",
"sess_close",
"sess_read",
"sess_write",
"sess_destroy",
"sess_gc");
session_start ();
?>
After completing the above steps, use require("session_inc.php") instead of session_start() in the program. Other session functions should still be called in the same way as before.
【The copyright of this article is jointly owned by the author and Aosuo.com. If you need to reprint, please indicate the author and source】

The above introduces the method of saving session in database and using database to save session, including the content of saving session in database. I hope it will be helpful to friends who are interested in PHP tutorials.