Warning: mysql_fetch_assoc() expects parameter 1 to be resource, null given : <p>I got this really weird problem that </p>

<pre><code>Warning: mysql_fetch_row() expects parameter 1 to be resource, null given ...
</code></pre>

<p>however, I checked mysql_num_rows($result), and it is not 0.</p>

<pre><code>    echo '&lt;h3&gt;Comments&lt;/h3&gt;';
    $comment_query = "select * from comments where post_id='$post_id' order by comment_timestamp desc";
    $comment_result = mysql_query($comment_query) or die(mysql_error());
    if (mysql_num_rows($comment_result) != 0) {
      while ($crow = mysql_fetch_assoc($commment_result)) {
        $comment_username = $crow['username'];
        $comment_text = $crow['comment_text'];
        $comment_time = $crow['comment_timestamp'];
        echo "&lt;b&gt;$comment_username &lt;/b&gt;&lt;b&gt;$comment_timestamp: &lt;/b&gt; &lt;br /&gt;".$comment_text."&lt;hr /&gt;&lt;br&gt;";
      }
    } else { echo "No comments yet!"; }
</code></pre>

<p>Any ideas on that? I have been stuck with it for a while, really thanks for your help!</p>
