1 Reply Latest reply on Oct 18, 2016 10:31 AM by lenaic.ridinger

    Data blending with source priority

    Clay McNeff

      Hello all. I'm new to Tableau and the online community. I have a question that I'm hoping is quick to resolve. I'm hoping it's a minor data blending issue, but when a calculated field is added to the mix, I'm struggling to fix it. See the data below:

       

      Table A:

      Table A.JPG

      Table B:

      Table B.JPG

       

      I would like to group by release. However, there is a substantial amount of data that I would like to capture that has no release information given. In those cases, I've created a second data source (Table B) to assign a release based on the employee name. I want to blend these 2 release fields together into one.

       

      Normally in Excel, I'd created a calculated field that would, if not null, report the release from Table A, and if null, perform a VLOOKUP to report the release from Table B. But when in Tableau, when trying to use an if calculation to do the same thing, I'm running into issues with aggregate vs. non-aggregate data. I'm willing to bet it's a simple data blending issue, but I do not know how to resolve.

       

      There is a potential wrinkle because certain names can theoretically be associated with different releases. For example, I want Table A's relationship between release and name to trump Table B's, so that John Smith's work in release 1.1 and 3.1 can still be funneled into the groups 'Release 1" and "Release 3" respectively, and only his work without an identified release be tagged with "Release 1 (not identified)" and therefore funneled into the "Release 1" group.