title: Fatal error: Call to a member function query() on null in
body: <p>Hello i just want write own function to get option value from mysql. My index.php file looks in this way: </p>
  
  <pre><code>&lt;?
  include ('config.php'); // here i have database connection details
  include ('global-functions.php');
  include ('minifier.php');
  include ('cache-start.php');
  ?&gt;
  &lt;!DOCTYPE html&gt;
  &lt;html lang="jezyk strony z bazy danych"&gt;
  USTAWIC META! sekcje head&lt;br&gt;
  Sprawdzić czy dodac przekierowanie w php z www na bez www !!
  &lt;head&gt;
  
      &lt;meta charset="utf-8"&gt;
      &lt;meta http-equiv="X-UA-Compatible" content="IE=edge"&gt;
      &lt;meta name="viewport" content="width=device-width, initial-scale=1"&gt;
  
  
  (...) rest of the file
  </code></pre>
  
  <p>config.php file looks: </p>
  
  <pre><code>&lt;?php
  
  $host = "localhost";
  $dbname = "xxxx";
  $username = "xxx";
  $password = "xxxx";
  
  // Create connection
  $conn = new mysqli($host, $username, $password, $dbname);
  
  ?&gt;
  </code></pre>
  
  <p>Now i try to do function to take specified option, i put this function in global-functions.php: </p>
  
  <pre><code>&lt;?php
  
  
  // Get option
  
  function get_option( $option_name ) {
  
      $sql = "SELECT opcja_value FROM opcje WHERE opcja_name='" . $option_name . "'";
      $result = mysqli_fetch_array($conn-&gt;query($sql));
  
      return $result[$option_name];
  
  }
  
  ?&gt;
  </code></pre>
  
  <p>Now i going to call function to get value of my option. So:</p>
  
  <pre><code>echo get_option('cache');
  </code></pre>
  
  <p>or doing simple if :</p>
  
  <pre><code>if ( get_option('cache') == '1' ) {
   // do stuff
  } else {
   echo 'option disabled, sorry :(';
  }
  </code></pre>
  
  <p>After call function i get Fatal error: </p>
  
  <blockquote>
    <p>Fatal error:  Call to a member function query() on null in
    /framework/includes/global-functions.php on line 10</p>
  </blockquote>