Check record exists db - error show

Question

How do I check if username or email exists and then put a error message in my error array. Right now i have:

$sql = \"SELECT username, email FROM users WHERE use         


        

Answer 1

Sounds like you're trying to let users know whether a username or email already exists at registration time. Here's what you can do:

 0){

   //----------------------------------------
   // Username already exists
   $error[] = 'Username already exists';

   //----------------------------------------
   // Return error to user and stop execution
   // of additional queries/code
} else {

  //----------------------------------------
  // Check if email exists

  //----------------------------------------
  // Create query
  $emailQuery = 'SELECT email FROM users WHERE email="'.mysql_real_escape_string($email).'"';

  //----------------------------------------
  // Query the db
  $emailResult = mysql_query($emailQuery);

  //----------------------------------------
  // Check if the result is empty
  if(mysql_num_rows($emailResult) > 0){

     //----------------------------------------
     // Email already exists
     $error[] = 'Email already exists';

     //----------------------------------------
     // Return error to user and stop execution
     // of additional queries/code
  } else {

     //----------------------------------------
     // Continue with registration...
  }
}
?>

Please note that you should always escape your values before executing the actual query.

Additional Resources:
http://us.php.net/manual/en/function.mysql-real-escape-string.php http://us.php.net/manual/en/function.mysql-escape-string.php