var_dump("UPDATE".$this->topString($this->limit,$this->offset)." $this->table SET ".implode(", ",$values).$this->whereString(),$parameters);
die;
var_dump('----a-----');
// joins in UPDATE are supported only in MySQL
$return=$this->query("UPDATE".$this->topString($this->limit,$this->offset)." $this->table SET ".implode(", ",$values).$this->whereString(),$parameters);