Boolean value in Output hyper file is different from the preview view in Tableau Prep when using data from Tableau Server

Published: 13 May 2022
Last Modified Date: 08 Jun 2022


When creating a Boolean Calculation field using the same filed name in Tableau Prep, the results are not correct. the TRUE turned to FALSE.
This issue does not happen to a local file, only for published data.
This issue does not happen to INT or STRING field, only to the Boolean field.

For example, creating a Boolean calculation like the below image. The field name is used in the calculation.
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The data in the preview view in Tableau Prep looks good:
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However, in the hyper file output of running the flow, all the values in the [Replace] field are changed to False.

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  • Tableau Prep Builder
  • Tableau Server 
  • Tableau Cloud


Please use the below workarounds to avoid this issue.

Option 1
Use INT or STRING field instead of Boolean.

Option 2
Create a new Boolean calculation field (like [Replace 2])in Tableau Prep.
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This issue is still under investigation by Tableau development.
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