title: PHP Warning: mysqli_stmt::bind_param(): Number of variables doesn't match number of parameters in prepared statement
body: <p>Not sure why I'm getting this PHP warning message.  It appears there are four parameters in the prepared statement, and also four variables in bind_param().  Thanks for any help! </p>
  
  <pre><code>  if($stmt = $mysqli -&gt; prepare("SELECT url, month, year, cover_image FROM back_issues ORDER BY year DESC, month DESC")) {
     $stmt -&gt; bind_param("ssis", $url, $month, $year, $cover_image);
  
     $stmt -&gt; execute();
  
     $stmt -&gt; bind_result($url, $month, $year, $cover_image);
  
     $stmt -&gt; fetch();
  
     while ($stmt-&gt;fetch()) {
       echo "&lt;li class='item'&gt;&lt;a href='$url'&gt;&lt;img src='$cover_image' alt='$cover_image' width='' height='' /&gt;&lt;/a&gt;&lt;br /&gt;&lt;span class='monthIssue'&gt;$month $year&lt;/span&gt;&lt;/li&gt;";
     }
  
     $stmt -&gt; close();
     $mysqli -&gt; close();
  
   }
  </code></pre>