public function delete($table, $data, $conjunction = 'AND'){
        $keys = array_keys($data);
        $pairs = Array();
        foreach($keys as $key){
            $pairs[] = "{$key}=:{$key}";
        }//foreach
        $pairs = implode(" {$conjunction} ", $pairs);
        return $this->query($this->set("DELETE FROM {$table} WHERE {$pairs}",$data));
    }