Updated to use directories, encoders, retry loops, ...

FoundationDbDemo1.cs

private static async Task Demo()
{
	var cancellationTokenSource = new CancellationTokenSource();
	using (var db = await Fdb.OpenAsync())
	{
		// open the "my_app/my_data" folder (created if missing)
		var folder = await db.Directory.CreateOrOpenAsync(new [] { "my_app", "my_data" }, cancellationTokenSource.Token);

		var firstId = Guid.NewGuid();
		var firstSequence = new[] { "foo", "bar", "baz" };

		// create a composite key encoder and merge it with the subspace
		// => encodes keys and append the correct prefix in a single step!
		var location = new FdbEncoderSubspace<Guid, int>(
			folder,
			KeyValueEncoders.Tuples.CompositeKey<Guid, int>()
		); 

		// create a value encoder that encodes UTF-8 strings
		// => could use any encoding scheme, including json or tuples, doesn't really matter.
		var encoder = KeyValueEncoders.Values.StringEncoder;

		// writing the data:
		await db.WriteAsync((trans) =>
		{
			var version = 0;
			foreach (var item in firstSequence)
			{
				trans.Set(
					location.EncodeKey(firstId, ++version),
					encoder.EncodeValue(item)
				);
			}
		}, cancellationTokenSource.Token);

		// get all items for a sequence:
		var items = await db.QueryAsync( 
			(trans) => trans
				.GetRange(FdbKeyRange.StartsWith(location.Partial.EncodeKey(firstId)))
				.Select(kv => encoder.DecodeValue(kv.Value)),
			cancellationTokenSource.Token
		);
		foreach(var item in items) Console.WriteLine(item);
		// output: foo, bar, baz

		// get all items starting with the third:
		items = await db.QueryAsync( 
			(trans) => trans
				.GetRange(FdbKeyRange.StartsWith(location.Partial.EncodeKey(firstId)))
				.Skip(2) // ok with small offsets !
				.Select(kv => encoder.DecodeValue(kv.Value)),
			cancellationTokenSource.Token
		);
		foreach (var item in items) Console.WriteLine(item);
		// output: baz

	}
}