8 Replies Latest reply on Jun 8, 2016 2:32 PM by Erin Gehn

    Extracting a Datablended Workbook

    Erin Gehn

      I've searched for this question and have found similar questions. However, the vocabulary seemed a bit different, so perhaps the issue is entirely different?

       

      I have a workbook that has datablended two datasources- let us call them DS1 and DS2 for easy reference.

      DS1 extracted fine, no errors or issues.

      DS2's extract took longer and came back with an error message. The message suggested that my calculations ((that included fields from DS1)) were invalid.

       

      Are you not able to extract blended data?

       

      >>Our ultimate goal is to assign an extract refresh so that this workbook (of both DS1 and DS2) can run overnight every night.<<

       

      Does anyone have any ideas or insight to this process?

      Are these extracts allowed within Tableau? If they are, then I will post a workbook to see what the real issue is.

       

      Thank you in advance!!

        • 1. Re: Extracting a Datablended Workbook
          Simon Runc

          hi Erin,

           

          Yes I've come across this issue!!...can I just check a few things first (so I'm sure I get the exact issue)...I'll give my understanding, and let me know where I go wrong!

           

          You have a model on Desktop with 2 datasources, which have been extracted to TDEs (where some of the calcs in DS1 use, blended, fields from DS2)

          You then want to publish each of the these TDEs to server, with a refresh schedule...so you publish each to server, and then (plan) to do the 'Replace Datasource' on each one, so you have a model connected to server-side TDEs. However when you publish the primary (DS1) you get the warning

          You then (plan) to publish this workbook to server

           

          Can you also let me know which server version you are working (9.3, which we don't have in production yet, has a nifty new option to publish and switch in one go...and I've not played with this, in this (blended) scenario yet.

          • 2. Re: Extracting a Datablended Workbook
            Erin Gehn

            "...so you publish each to server, and then (plan) to do the 'Replace Datasource' on each one, so you have a model connected to server-side TDEs. However when you publish the primary (DS1) you get the warning"

             

             

            All was correct besides the above. The error message appears after both datasources have been extracted. At this point, I have yet to publish because the extract did not allow me to use both datasources in one calculation.

            I don't know what the replace datasource feature is.

            We have 9.3.

            • 3. Re: Extracting a Datablended Workbook
              Simon Runc

              I don't know what the replace datasource feature is

              Pre-9.3 you weren't able to publish and switch in one go...so we'd have a model with a local TDE, we'd have to publish that to server, then re-open that (server-side) datasource in the model, then switch datasource, so the model was now pointing at the server-side version, then close the local and publish...very painful!

               

              So your 'development' (desktop) model has uses Live datasources (say to SQL Sever), but you now want to extract this into a TDE?

               

              I've not used 9.3 server (in anger) yet, so may have a few more Qs!!

               

              If you first create an extract for DS2...what does the (blended) calculations in DS1 say?...are they referencing the DS2 TDE?

               

              The reason I ask is that, my method is to publish DS2 to server, add that back as a datasource. Then I do the 'replace datasource' switching the Local TDE to the server one...this should now replace the 'blended' calculation in DS1 so they now reference the  server-side DS2...I then do the same with DS1...and then I publish the workbook (I get the warning 'contains references to DS1, so will only work in this workbook' which I OK through). I've found the order I do this (DS2 then DS1) is key...On 9.3 the publish (as extract) and switch is done in one go, so not sure exactly how (if at all) this new feature handles blended fields...btw this is still a fairly painful process!! (using the 'replace datasource' (in the Data menu) can break some of the settings Vizible Difference: Replacing Data Source Breaks Everything: Cause, Workaround & Ultimate Fix

              • 4. Re: Extracting a Datablended Workbook
                Erin Gehn

                Oh okay...yes, that does sound painful. I am not familiar with this process.

                 

                Yes, the datablending works on a live connection with Oracle SQL Server, but we would like to extract it nightly so that both datasources are pulling the same amount of data.

                 

                The datasource with the dual-data-source functions is not able to extract without error, regardless if this datasource is extracted first or extracted last.

                The other datasource is without error both live and with the extract. If it is noteworthy, this is the primary datasource.

                 

                You have lost me within this paragraph...

                • 5. Re: Extracting a Datablended Workbook
                  Simon Runc

                  So with the exception of models which we plan to run Live (basically if we have 100+ Million rows, we use ExaSol), I always use extracts, and is the first thing I do (...connect to SQLView -> Create Extract). So not come across a situation where a model is built live and then extracted (and not with Blended)...However, and this is a bit of a guess!!

                   

                  Could you...Remove the 'Blended' part for the calculations, so say you had a calculation

                   

                  SUM([Sales])*AVG([BlendedDataSource.ExchangeRate])

                   

                  change this to SUM([Sales])*1

                   

                  Copying and pasting the original equation into notepad (or similar) so we can put back later....Then create the extracts for both datasources (which it should allow you do, as you no longer have blended formulas). Then go back and re-type the original blended formula back in (hopefully you can copy and paste this from your notepad...but if you get an error, you may need to manually re-instate the blended part.

                   

                  This way you should have 2 TDEs, with blended formulas (referencing a TDE)...as I said a bit of guess.

                   

                  Let me know how you get on, as if this doesn't do the trick, I'll reach out to some of the other Tableau Ambassadors who may have more knowledge on this.

                  1 of 1 people found this helpful
                  • 6. Re: Extracting a Datablended Workbook
                    Erin Gehn

                    Oh okay!

                    According to the sources I sought before with the differing vocabulary, I think your suggestion lines up exactly.

                    I shall follow up with an update shortly!!

                    (Thank you!!)

                    • 7. Re: Extracting a Datablended Workbook
                      Simon Runc

                      Excellent news!...I did used to articulate things in human language before spending too much time on the forums/reading-Tableau-books!!

                       

                      Interested to see how you get on, always like to see how a story ends! (and as we will be moving to 9.3, or straight to 10, very soon I will be interested in how you get on...I feel it's something they have overlooked [certainly when you develop everything locally, and then move to server] as this was more time-consuming/frustrating than I thought it would be, when I first had to publish something like you have here)

                      • 8. Re: Extracting a Datablended Workbook
                        Erin Gehn

                        Haha. Well I think my confusion shows proof of your fluency. Good job!

                         

                         

                        So....I tried unextracting, un-calculating, reextracting, recalculating  to no avail.

                        I tried a few other things but...

                        In the end, the main issue was that I had forgotten I had included a parameter value. You cannot extract parameter values. Ugh.

                         

                        But it works!!

                        And it would not have worked had you not suggested I keep a calculation constant prior to extracting.

                         

                        Thank you so much for your insight!!