You can use below mentioned code
//database read adapter
$read = Mage::getSingleton('core/resource')->getConnection('core_read');
$results = $read->fetchAll("select * from your_tablename");
foreach($results as $r$row)
{
var_dump($r);echo "<i><b>Author Name:</b></i>";
echo $row["name"];
echo "<br /><i><b> Comment: </i></b>";
echo $row["comment_txt"];
echo "<br /><i><b>Date: </i></b>";
echo $row["comment_date"];
echo "<br><br>";
}