Unable To Change Data Type Of Multiple Fields In Bulk

Published: 12 Dec 2019
Last Modified Date: 08 Jul 2022


Tableau Prep Builder automatically assigns certain data type of fields when connecting to a text file and unable to change them in bulk.


  • Tableau Prep Builder
  • Text Files


Possible workaround:
Option 1: Open the text file by Tableau Desktop with schema.ini, then extract data.
  1. Create schema.ini to define data types of columns in a text file.
    For more details about schema.ini, see Create a schema.ini File.
  2. Open the text file by Tableau Desktop.
  3. Extract data and saved as a hyper file.
  4. Open the hyper file by Tableau Prep Builder.
Option 2: Use a database which allows to define data type of columns at the data source side instead of the text file.


The ability to change data type of multiple fields is not built in a product currently.
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