mapbuilder markers

I am trying to load markers from a mysql db using mysqli functions. I use the following code:

while ($row = mysqli_fetch_assoc($schoolResult)){
$map->addMarker($row['latitude'], $row['longitude'], array(
'title' => $row['schoolName']
));
}

If I attempt to create the markers the map does not display. If I don't create the markers the map does display. Do you know why this is happening?

Thanks.

Hello, I need to see your full code to give you an advice.

I think I have it figured out. It looks like a memory issue - too many markers were being created - I am talking to our admin about it. Thanks. Very nice class by the way!