Hi Francesco,
Thank you for prompt reply.
- I'm using MySQL db.
- Yes, The query dataset used as cached in cockpit.
It's string type for that columns.

I've unticked the use cache and it's working. But when i apply to another dataset and prompt error as below:

Do i need to raise a new question for this issue? and Knowage log file no record this error.
Thank you.
Regards,
Herman.