Use TableContinuationToken as bookmark

Question

This query taken from here is quite straight forward:

TableContinuationToken token = null;
List<Footwear> shoes = new List<Footwear>();

do
{
  TableQuerySegment<Footwear> queryResult = query.ExecuteSegmented(token);
  token = queryResult.ContinuationToken;
  shoes.AddRange(queryResult.Results);
} while (token != null);

Once null is returned the while loop finishes. Is it possible to store the last TableContinuationToken and then check after a while if there is more Footwear entered after the last TableContinuationToken. To create 'order' I use this approach.

PS:

I hope the following provides a bit more context. I currently store instances of this class:

public class SomeClass : TableEntity
{
    public long Ticks { get; set; }
    public SomeClass(){}

    public SomeClass(string partitionKey)
    {
        PartitionKey = partitionKey;
        Ticks = DateTime.UtcNow.Ticks - DateTime.MinValue.Ticks;
        // rowkey + partition = guid/pk
        // used to order events at the other end - very important  
        RowKey = (DateTime.UtcNow.Ticks - DateTime.MinValue.Ticks).ToString();
    }
}

in Azure table storage. To create a rowkey like this allows me to sort entities like so:

var query =
(from s in _table.CreateQuery<SomeClass>()
where
s.PartitionKey == _partitionKey &&
string.Compare(s.RowKey, rowKeyToUse, StringComparison.Ordinal) > 0 
select s).AsTableQuery(); 

from time to time I want to check if there are new entities. I do not think I can use the rowkey for this (see also here). So currently I store the latest Ticks of the last entity in the process that consumes the table storage. I can use this query to pull for new entities:

 var query =
  (from s in _table.CreateQuery<SomeClass>()
   where
   storedEvent.PartitionKey == _partitionKey &&
   storedEvent.Ticks > _ticks && // only above last threshold
   string.Compare(s.RowKey, rowKeyToUse, StringComparison.Ordinal) > 0 
   select s).AsTableQuery();

So in a nutshell - this is what I want to achieve:

(1) Page over all entities until token = null. (2) 'Pull' the table storage. If there are new entities loop until token = null. (3) Repeat (2)

I am after the simplest and most robust approach. Currently I am using the Ticks approach described above. However, this feels wrong as the same information is already stored in the rowkey as string. I hope this makes sense.

Answer 1

If you store the partition key and row key of the final entity returned, you can execute a TableQuery in the future to check this. The filter should be partition key = to that entity's partition key (like you already have) and row key > that entity's row key. Then you can use the exact same code you already have.