Tableau Prep outputs values with incorrect number format to external Oracle database

Published: 22 Jul 2021
Last Modified Date: 08 Jul 2022


After Tableau Prep's output of Excel data file to Oracle database, the new database table shows negative and false numbers unlike in Tableau Prep.

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  • Tableau Prep 2021.2.1
  • Windows 10
  • Oracle


Instead of using Oracle OCI driver, follow these steps below to use Oracle JDBC driver (ojdbc8.jar)

1: Go to Control Panel -> Uninstall a Program

2: Search for "oracle" and uninstall anything like "Tableau202x. ... Oracle Driver"

3: Download the Oracle JDBC driver (ojdbc8.jar) from

4: Copy the .jar file to this folder: C:\Program Files\Tableau\Drivers


Beginning with version 2020.2, Tableau recommends that you use the JDBC driver with this connector. The newer JDBC driver resolves some limitations found with the OCI driver.
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