Unable to Update Datasource in Published Dashboard After Upgrading Database

Published: 28 Mar 2017
Last Modified Date: 29 Mar 2017


When connected live to Oracle and concatenating 11 strings or more with at least one string being a date part converted into a string, the following error might occur:

Oracle database error 28: ORA-00028: your session has been killed ORA-00028: your session has been killed


  • Tableau Desktop
  • Oracle


Option 1

  1. Extract the data connection
  2. Create the calculated field
  3. Wrap the desired calculation in an aggregation, such as MAX()

Option 2 

Use a different method to create the same string.
For example, if the original calculation was created to put a strictly formatted date into a title, then the date can be added to the title without converting it into a string. Dates in titles, legends and filters can be formatted by changing the default date format for the field.


Due to the way Oracle handles string values, the query that Tableau Desktop sends to the Oracle data source is necessarily complex.
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