static function makeUpdateQueryFromQueryManager(UpdateQueryManager $queryManager){
$i = 1;
foreach ($queryManager -> getUpdatedVars() as $field => $var){
$placeholders['set'] .= $field.' = ?';
if (count($queryManager -> getUpdatedVars()) != $i){
$placeholders['set'] .= ', ';
}
$i++;
}
$query = 'UPDATE '.$queryManager -> getModel() -> getTable().' SET '.$placeholders['set'].''.$placeholders['comparision'].';';
return $query;
}