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"ERROR: non-NULL value required" when running a flow containing filter and left join or right join


Published: 13 Sep 2019
Last Modified Date: 26 Feb 2020

Issue

When running a flow containing a string filter in the right hand side table of a left join, the following error occurs:

Failure evaluating to database: ERROR: non-NULL value required

Environment

  • Tableau Prep Builder

Resolution

Upgrade to Tableau Prep Builder 2020.1.1 or later.

Cause

This behavior is related to known issue ID 976395.
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