[question] Paging

[victor-nerdunited]

If my query results return over 200 documents, I get a 405 error (No open transaction). I noticed if I use the console in AWS the call to ExecuteStatement returns a response that has a NextPageToken field. I assume this is what would be used for paing (like Google BigQuery or Azure Cosmos DB). Is this something that is on the roadmap to be implemented in the driver?

[trstephen-amazon]

Hi @victor-nerdunited , thanks for letting us know (and apologies for the delay!)

I tried to reproduce the behavior with an integration test

[TestMethod]
public void Execute_ManyDocuments_NoFetchError()
{
    Logger.Info($"Seeding documents in {Constants.TableName}");

    var insertQuery = $"INSERT INTO {Constants.TableName} ?";
    Enumerable.Range(1, 250).ToList().ForEach(i =>
    {
        var ionStruct = ValueFactory.NewEmptyStruct();
        ionStruct.SetField(Constants.ColumnName, ValueFactory.NewInt(i));

        qldbDriver.Execute(txn => txn.Execute(insertQuery, ionStruct));
    });

    Logger.Info($"Finished seeding {Constants.TableName}");

    var selectQuery = $"SELECT * FROM {Constants.TableName}";
    int docCount = qldbDriver.Execute(txn => txn.Execute(selectQuery).ToList().Count);

    Assert.AreEqual(250, docCount);
}

This passed without issue. I added some extra logging (and sniffed around on the backend) to verify that FetchPage [code, docs] was used. As expected, I see a single FetchPage call for the additional 50 results.

Are you able to share code that can reproduce the error?

edit: I wrote a similar test for the async driver. Again, couldn't reproduce the failure