5 Replies Latest reply on Feb 11, 2016 1:48 AM by jon schofield

    Every time I refresh an extract i get message "loading data source for the first time, please create an extract"

    jon schofield
    jon schofield Feb 9, 2016 1:51 PM

      Hi,

       

      I'm hoping someone may be able to help as this has me tearing my hair out!

       

      I have a twb file reading from a data extract that is connected to an excel file. The excel file is around 600,000 rows and 15 columns. It has an index column set up to allow for incremental extract refreshing.


      Now the workbook works fine but when I refresh the extract the dialog box sticks on a message along the lines of "loading data source for the first time, please create an extract for faster start up". I don't understand this as I have been reading from this extract for around 6 months, so it is definitely not the first time! It is starting to become a pain as the dialog box sticks on this for around 7 minutes, before reading the rows and refreshing the extract in about another 1.5 minutes. The application that I'm using tableau for in this case would really benefit from a faster load time as I would like to be able do analyse the recorded data as shortly after it is uploaded to the excel file as possible.

       

      For further info, I am running version 9.2 for windows on a MacBook air running parallels. The excel sheet, extract and twb file are all stored on the windows C drive of the virtual machine.

       

      Any suggestions as to what is going here and any help provided would be much appreciated! If you need any further information to assist, please do ask and I can try to provide it..

       

      Thanks,

       

      Jon

        • 1. Re: Every time I refresh an extract i get message "loading data source for the first time, please create an extract"
          Nathan Panuco
          Nathan Panuco Feb 9, 2016 4:12 PM (in response to jon schofield)

          Hey Jon! I'm not sure that I can pin down what is wrong, but hopefully can give a bit of guidance where to look:

           

          Hope this helps!

          • 2. Re: Every time I refresh an extract i get message "loading data source for the first time, please create an extract"
            jon schofield
            jon schofield Feb 10, 2016 1:46 AM (in response to Nathan Panuco)

            Hi Nathan,

             

            Thanks for taking the time to send this info over, appreciate it! Unfortunately I have browsed some of these links before and can't find anything that seems relevant to my problem..


            The strange thing is that I'm not having the same problem with other extracts. I've tried deleting the extract, creating a new one or connecting through a new tab but still have the same issue..!

            • 3. Re: Every time I refresh an extract i get message "loading data source for the first time, please create an extract"
              Stephen Shields
              Stephen Shields Feb 10, 2016 7:20 AM (in response to jon schofield)

              I am a Mac user, no Parallels/Microsoft, I encountered similar messages going between 8.X versions and into 9.X. The workbook that I use where files are refreshed locally (on my machine) I have set up as "Live" connections, and the workbook is not saved as a "Packaged Workbook". Each day the files are updated, once I have those in place the workbook opens grabbing the new data and updates accordingly.

               

              Shawn's comment on appending data from file does work well, if you have the Beta for 9.3 you can use the "Union" feature which works even better; however I have found that when you get into the millions of rows from 10's of files the update can be a bit egregious albeit Tableau says that they are looking into improving the crunching time.

               

              Regardless, I would consider trying to make the workbook ping the file as a 'live' connection as opposed to an extract.

              1 of 1 people found this helpful
              • 4. Re: Every time I refresh an extract i get message "loading data source for the first time, please create an extract"
                Jonathan Drummey
                Jonathan Drummey Ambassador Feb 10, 2016 8:02 AM (in response to jon schofield)

                I'm a Parallels user as well.

                 

                If what you're describing is the case (raw data is Excel, using a Tableau Data Extract, every time you refresh the extract you get the "loading data source for the first time..." message) it sounds like a bug, I suggest reaching out to Tableau tech support. However if you have other Excel files that are live connections in that workbook they would be the ones generating the message.

                 

                The reason why the "loading data source for the first time..." message is supposed to show up is that the "new connector" for Excel & text sources introduced in Tableau v8.1 is actually the same Tableau data engine that extracts use. When we use the new connector for a live connection then when Tableau opens the workbook Tableau creates an extract in the background***. That can take awhile so Tableau is displaying that message to let us know that there's a way to avoid that startup time.

                 

                *** One side-effect of this is that if you haven't made any changes that would require refreshing the shadow extract then creating an extract on a text or Excel file is instantaneous since Tableau already did the heavy lifting when you opened the workbook.

                 

                Jonathan

                • 5. Re: Every time I refresh an extract i get message "loading data source for the first time, please create an extract"
                  jon schofield
                  jon schofield Feb 11, 2016 1:48 AM (in response to Jonathan Drummey)

                  Jonathan, Steve, Shawn. Thanks so much for your replies, really great of you.

                   

                  Shawn's reply seems to have disappeared from the feed. I'm not sure I fully followed his explanation of the "loading for the first time" issue. I also had specifically set up the incremental refresh to avoid this..

                   

                  His suggestion to merely append the data from file was useful though. I had initially avoided appending to the extract as it does not give you the option to easily change the data source and refresh if any errors are made in the data that is appended. I've now changed my data storage to allow for both.

                   

                  I now have a "master" excel file where hold all data so-far add each new piece of data ( each piece is a "session" ~3000 rows per new session), I've created an extract from this once but do not refresh it each time a session is added. Instead I also now have a "temp" excel file where I just hold the latest session data, I append to the extract from this file (takes around 45 seconds). If I make a mistake in the session added from the temp file then I can correct the mistake, change it in the master file and perform a full refresh.

                   

                  Shawn; I'm looking forward to "Union" in V3, I anticipate needing to use this in the future..

                   

                  In the meantime I'm going to try using the method outlined above but will chase tableau support for some more help like this as it does seem like a bug. Also it seems like exactly the issue that incremental refreshes are designed to support..

                   

                  Thanks for your help guys. Any further suggestions would be appreciated and I'll keep you up to date if I get anything back from support.

                   

                  J