select(...columnNames) {
        return this.__newInstance__(
            Object.assign(
                {},
                ...columnNames.map(column => {
                    return { [column]: this.get(column) };
                })
            ),
            columnNames
        );
    }
Select columns into the Row.
@param {...String} columnNames The columns to select.
@returns {Row} A new Row containing only the selected columns.
@example
row.select('column1', 'column2')