String Fields with More Than 255 Characters Are Truncated When Connecting to Databricks in Tableau Desktop

Publish Date: Dec 26, 2025

Description

When connecting to Databricks from Tableau Desktop, if a String field has more than 255 characters, the string will be truncated to 255 characters.

Cause

The truncation of the 'string' field to 255 characters is caused by a default String Column Length within SparkSQL ODBC driver.

Resolution

Option 1 (recommended)

Use a TDC file to increase the String Column Length:

<?xml version='1.0' encoding='utf-8' ?>
<connection-customization class='databricks' enabled='true' version='10.4'>
<vendor name='databricks'/>
<driver name='databricks'/>
<customizations>
<customization name='odbc-connect-string-extras' value='DefaultStringColumnLength=500' />
</customizations>
</connection-customization>

Option 2

Change the default value from DSN setup and then use Other Databases (ODBC) connector:

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