How to generate a random session variable in php

Question

i want to generate a random session variable and insert the variable in a mysql record to use later to validate an account set up.
person fills out form to create account and submits; inserts form information in mysql record.
i want the random variable to be inserted from a hidden field and the page sends an email with a link to click on to compare the variable to validate the user.
Not sure how to generate a random session variable and get that to the hidden field value to be inserted with the other form information.
thanks for your help,
Jim Balthrop

Answer 1

To insert the key I would personally do something like...
$key = md5($username . $password . $salt);
Insert that into your MySQL database, then send them a email with it, my next code shows how to activate it.
This is to activate the account.
<?php
$key;
$errors = array();
if(isset($_GET['key']){
     $key = $_GET['key'];
     $sql = 'SELECT * FROM users WHERE key = \'' . $key '\' LIMIT 1';
     $result = mysql_query($sql) or die(mysql_error());
     if(mysql_num_rows($result)){
          $sql2 = 'UPDATE users SET active = 1 WHERE key = \'' . $key '\' LIMIT 1';
          $result2 = mysql_query($sql2) or die(mysql_error());
          if($result2){
               //successfully activated account
          else{
               //Something Went Wrong!
     else{
          $errors[] = 'Invaild Key, Please try again!';
else{
     $errors[] = 'Invaild Key, Please try again!';
?>