loops mixed up with MySQL

Question

I'm writing a simple message board where you can reply to any thread and then reply to any reply and so on.... everything works well but is there a simple method to loop the query as this could potentiality go on and on and on

    $rsql = "SELECT * FROM rotd_mb WHERE reply='N' ORDER BY dateTime DESC";
$result = runSQL($rsql);
while ($row = mysql_fetch_array($result)) {
echo "".$row[title]."";
    $rsql2 = "SELECT * FROM rotd_mb WHERE reply='Y' AND replyID='$row[messageID]' ORDER BY dateTime DESC";
    $result2 = runSQL($rsql2);
    while ($row2 = mysql_fetch_array($result2)) {
    echo "".$row2[title]."";
        $rsql3 = "SELECT * FROM rotd_mb WHERE reply='Y' AND replyID='$row2[messageID]' ORDER BY dateTime DESC";
        $result3 = runSQL($rsql2);
        while ($row3 = mysql_fetch_array($result3)) {
        echo "".$row3[title]."";
        }
        mysql_free_result($result3);    
    }
    mysql_free_result($result2);    
}
mysql_free_result($result);

Answer 1

You could try UNION, probably not the best solution but it will work

$sql = "SELECT * FROM rotd_mb WHERE reply='N' ORDER BY dateTime DESC
        UNION
        SELECT * FROM rotd_mb WHERE reply='Y' AND replyID='$row[messageID] ORDER BY dateTime DESC
        UNION
        SELECT * FROM rotd_mb WHERE reply='Y' AND replyID='$row2[messageID]' ORDER BY dateTime DESC";

A better idea would be to re-design your database table structure.