Error when trying to load a dataset after integrating Unity Catalog metadata with Power BI

Increase the byte limit in your ODBC settings and use the native query option in Power BI.

Written by guruprasad.bn

Last published at: March 12th, 2025

Problem

When integrating Unity Catalog metadata with Power BI and attempting to load a dataset, you encounter the following error message. 

One or more errors occurred. ODBC: ERROR [HY000] [Microsoft][DSI] (20039) Cannot store ""."".""."REMARKS" value in temporary table without truncation. (Column metadata implied a maximum of 512 bytes, while provided value is xxx bytes).

 

Cause

The comment metadata in the dataset is too large to be handled by Power BI’s ODBC driver. By default, Power BI expects metadata to not exceed 512 bytes. 

 

Solution

First, update the ODBC connection string to increase the byte limit in the .ini file. Add the parameter MaxCommentLen=2048 to the ODBC string. This change increases the comment length limit to 2048 bytes, allowing Power BI to store longer metadata without truncation. 

 

Note

It is good practice to keep column comments within 512 characters when possible.

 

 

Then, use Power BI’s native query option in the UI to query the table directly. This bypasses some of the limitations in Power BI's regular data connectivity mode, ensuring that metadata issues are handled more gracefully. The following shows an example query in the native query field of Power BI’s UI.