import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: SizedBox(
          width: 200,
          // A `PaginatedDataTable` cannot be wrapped by a
          // `SingleChildScrollView`, because it provides its child
          // with an unbounded width.
          child: SingleChildScrollView(
            scrollDirection: Axis.horizontal,
            child: PaginatedDataTable(
              columns: <DataColumn>[
                DataColumn(
                  label: Text("1"),
                ),
                DataColumn(
                  label: Text("2"),
                ),
              ],
              source: CustomDataSource(),
            ),
          ),
        ),
      ),
    );
  }
}

class CustomDataSource extends DataTableSource {
  @override
  bool get isRowCountApproximate => false;

  @override
  int get rowCount => 1;

  @override
  int get selectedRowCount => 0;

  @override
  DataRow? getRow(int index) {
    return DataRow(

      cells: <DataCell>[
        DataCell(
          Text(
            "Some very long cell that is wider than 200 logical pixels, the size available to the table",
          ),
        ),
        DataCell(
          Text(
            "Same as the first cell, again some very long cell definetly forcing the table to be wider than 200 logical pixels",
          ),
        ),
      ],
    );
  }
}