public function select($columns = "*") : QueryBuilder
    {
        $this->_query[] = "SELECT";

        //Parse column(s)
        if(is_array($columns)) {
            $select_columns = "";

            $size = sizeof($columns);
            for($i = 0; $i < $size; $i++) {
                if($i > 0) {
                    $select_columns .= ', ';
                }

                $select_columns .= '`'. $this->sanitize((string)$columns[$i]) .'`';
            }

            $this->_query[] = $select_columns;

            return $this;
        }

        $select_columns = "*";
        if(
            !empty($columns) &&
            $columns !== "*"
        ) {
            $select_columns = '`'. $this->sanitize((string)$columns) .'`';
        }

        $this->_query[] = $select_columns;

        return $this;
    }