title: Call to undefined function mysql_query() with Login
body: <p>When i execute my <strong>PHP</strong> code below i get a <strong>Fatal error</strong> and i'm not sure how to resolve it.</p>
  
  <p>Thank you for your help</p>
  
  <p><strong>The Error</strong></p>
  
  <blockquote>
    <p>PHP Fatal error:  Uncaught Error: Call to undefined function mysql_query() in /Applications/MAMP/htdocs/lprapp/config.php:23
    Stack trace:#0 {main}
      thrown in /Applications/MAMP/htdocs/lprapp/config.php on line 23   </p>
  </blockquote>
  
  <p><strong>Code</strong></p>
  
  <pre><code>    &lt;?php
  
      $user = 'root';
      $password = 'root';
      $db = 'inventory';
      $host = 'localhost';
      $port = 8888;
  
      $link = mysqli_init();
      $success = mysqli_real_connect(
         $link,
         $host,
         $user,
         $password,
         $db,
         $port
      );
  
      ?&gt;
      &lt;?php
      $username = $_POST['username'];
      $password = $_POST['password'];
      $sql = mysql_query("SELECT * FROM login WHERE username = '".$_POST['username']."' and password = '".md5($_POST['password'])."'");
      $row = mysql_num_rows($sql);
      if($rom &gt; 0 )
      {
        session_start();
        $_SESSION['username'] = $_POST['username'];
        $_SESSION['password'] = $_POST['password'];
        echo "login done";
      }else {
        echo "fail login ";
      }
  
      ?&gt;
  </code></pre>