public async Task <IChunk> ReadSingleBackwardAsync(string partitionId, long fromUpperIndexInclusive, CancellationToken cancellationToken)
{
using (var connection = Connect())
{
await connection.OpenAsync(cancellationToken).ConfigureAwait(false);
using (var command = new SqlCommand(_options.GetLastChunkScript(), connection))
{
command.Parameters.AddWithValue("@PartitionId", partitionId);
command.Parameters.AddWithValue("@toUpperIndexInclusive", fromUpperIndexInclusive);
using (var reader = await command.ExecuteReaderAsync(cancellationToken).ConfigureAwait(false))
{
if (!reader.HasRows)
{
return(null);
}
await reader.ReadAsync(cancellationToken).ConfigureAwait(false);
var chunk = new MsSqlChunk
{
Position = reader.GetInt64(0),
PartitionId = reader.GetString(1),
Index = reader.GetInt64(2),
Payload = _options.Serializer.Deserialize(reader.GetString(3)),
OperationId = reader.GetString(4),
Deleted = reader.GetBoolean(5)
};
return(chunk);
}
}
}
}
public async Task <IChunk> ReadSingleBackwardAsync(string partitionId, long fromUpperIndexInclusive, CancellationToken cancellationToken)
{
using (var connection = Connect())
{
await connection.OpenAsync(cancellationToken).ConfigureAwait(false);
using (var command = new SqlCommand(_options.GetLastChunkScript(), connection))
{
command.Parameters.AddWithValue("@PartitionId", partitionId);
command.Parameters.AddWithValue("@toUpperIndexInclusive", fromUpperIndexInclusive);
return(await ReadSingleChunk(command, cancellationToken).ConfigureAwait(false));
}
}
}