Qlik Data Gateway ODBC (via direct gateway) Rocket U2 Universe - parsing error

[tens]

Hello,

I hope you're well. We're migrating Qlik Data Transfer to Qlik Data Gateway. We encountered some issues when we want to extract some datetime field from table store in Rocket U2 Universe.

We are using a custom ODBC connector (via Direct Access Gateway). We successfully setup the custom syntax, we can extract data from our table.

But when we want to extract a date field with some empty values, an parsing error is throwing by the connector.
We saw that in the new version, we can overload some type in a custom_mapping_type.json file. We've made the upgrade to the version 1.7.1 to test this feature. But we're lost about the identifier to use.
Is it possible to make it with the custom ODBC connector ? If yes how can I retrieve the identifier I need to use please ?

The bug seems to be an parser error when the request returns null value (blank value) in the date field.

Here's the bug when we try to parse the field:

2025-02-25 17:44:15,761 [ 79] [ERROR] DAG - RequestId=2ddbc183-8825-449a-bbe2-8d690c0a3190 ClientSessionId= ReloadId=b07ca406-cbdd-4327-99e9-accf8832246d AppId=fe06ed31-e963-4026-929b-3db67cf249d7 Message=agent-data-chunk-read-error: Status: Internal, Message: Failed to read data at {1:21}
Grpc.Core.RpcException: Status(StatusCode="Internal", Detail="Failed to read data at {1:21}")
at Grpc.Net.Client.Internal.HttpContentClientStreamReader`2.MoveNextCore(CancellationToken cancellationToken)

A workaround we tried to test is to use a function to cast the date field into string. Unfortunately, we didn't succeed at the moment because the Rocker U2 Universe drive doesn't authorize to use any function in the SQL part.

We already tried with multiple version of Rocker U2 Universe (version 5.1,5.2,5.3,5.4).

Some of you did already use successfully  Rocket U2 Universe driver with ODBC connector in Qlik Datagateway with a date field type ? 

Thanks a lot

[NadiaB · Accepted solution]

Hi @tens, unfortunately you will have to upgrade to a newer version, challenges to get the correct value to set in the identifier were reported in 1.7.2, I can't recall in which version but new logging was added to allow customers to find this value in the logs, I can confirm that in 1.7.5 the odbc-connector logs show now the "identifier", something like this:

2025-06-04 14:09:11,379 [ReadSourceData thread: <>] [INFO ] mysql ProcessId=11796 RequestId=NA ClientSessionId= ReloadId=NA Message=Going to retrieve custom type mappings of identifier 'MySQLODBC_sb64.dll'.