How to use database methods to save sessions
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 closes the browser's cookie for some security reason, the program Session related operations will not be performed. Therefore, if session data can be saved in the 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 $SESS_DBUSER";echo " MySQL Error: " . mysql_error();die;}
if (! mysql_select_db($SESS_DBNAME, $SESS_DBH)) {echo " Unable to select database $SESS_DBNAME";die;}return true;}
function sess_close() { return true; } function sess_read($key) { global $SESS_DBH, $SESS_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; //过期时间 $value = addslashes($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'"; $qid = mysql_query($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 it in the program require("session_inc.php") can be used instead of session_start(), and other session functions are still called in the same way as before.
This article describes how to save sessions through the database. For more related content, please pay attention to the PHP Chinese website.
Related recommendations:
Five ways to prevent SQL injection
##About the high availability of MySQL: Keepalived dual master Hot backup
#Use PHP to write several common sorting algorithm programs
The above is the detailed content of How to use database methods to save sessions. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

MySQL is an open source relational database management system. 1) Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2) Basic operations: INSERT, UPDATE, DELETE and SELECT. 3) Advanced operations: JOIN, subquery and transaction processing. 4) Debugging skills: Check syntax, data type and permissions. 5) Optimization suggestions: Use indexes, avoid SELECT* and use transactions.

In PHP, you can effectively prevent CSRF attacks by using unpredictable tokens. Specific methods include: 1. Generate and embed CSRF tokens in the form; 2. Verify the validity of the token when processing the request.
