public function quoteColumnName($column) 
    {
        if(strpos($column, '.') === false) {
            return $this->quoteBacktick($column);
        } else {
            $tokens = explode('.', $column);
            $numberOfTokens = count($tokens);
            if($numberOfTokens == 2) {
                return $this->quoteBacktick($tokens[0]) .'.'. $this->quoteBacktick($tokens[1]);
            } else {
                throw new \Exception("Columns name $column is not valid.");
            }
        }
    }