How do i fix this error in a PHP script?

[Brice]

Ok im trying to make a group page for this game and i keep getting an error. This is the error:
Unable to jump to row 0 on MySQL result index 20 on line 420

This is the line :
$result = mysql_result($query,$row,$column);

This is the whole code :
}
function result($query,$row=0,$column=0){
$result = mysql_result($query,$row,$column);
if(defined('DEBUG')){ if($result == true){ echo mysql_error($this->connection) . "<br />Query that errored: ".$this->lastquery; } }
return $result;
}