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Advocate I
Advocate I

Conversion from number to string failed due to undersized character buffer

Starting yesterday afternoon, several of our datasets have failed to refresh with the below error. What is the reason for this error? Our datasets imports data from Databricks Spark Delta tables using the Spark connector into our Premium P1 capacity. I have restarted the Databricks cluster once after this error started occurring, but it did not help.


There was an error when processing the data in the dataset.
Please try again later or contact support. If you contact support, please provide these details.
Data source error: ERROR [HY000] [Microsoft][Support] (50130) Conversion from number to string failed due to undersized character buffer.. The exception was raised by the IDataReader interface. Please review the error message and provider documentation for further information and corrective action. Table: MyTable.
Cluster URI:

We were facing same issue.

you can set configuration “spark.thriftserver.arrowBasedRowSet.enabled false” under Advanced options -> Spark tab in any Databricks and restart cluster.

This fixed the issue for us

Helper I
Helper I

I'm not an admin on my Databricks implementation, so I don't want to mess around with configurations under advanced options for my cluster if I can avoid it. But this update was just provided on the support page (, so I think I'll just hold and wait for this:


"Engineers are working on a fix and expect it to be deployed by end-of-day 07/01/2020."

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