8 Replies Latest reply on Jun 19, 2011 7:02 PM by Nathaniel Fitzgerald-Hood

    Extract Performance

    Russell Christopher

      Hey Folks -


      I'm working with a DW (SQL 2008 R2) which has 1 fact table containing about 12.5M rows and 6 associated dimension tables with between 9-20K members each.


      I chose to create an extract from this DW, and it took approximately 71 minutes, which sort of surprised me. (FYI, I'm on Tableau 6.0.6 -- the eval).


      On the same machine, I then fired up Excel & PowerPivot, and imported the same table(s) after bouncing the SQL Server to make sure nothing was in cache.


      PowerPivot loaded the same data in less than 3 minutes, obviously a huge difference. The final extract file for Tableau was about 1.1 GB, while the PowerPivot workbook was 250 MB


      Can anyone explain why this might be happening? A few guesses on my part - can anyone expand on same?


      - During extaction I see Tableau landing data to disk in temp files - Extra IO?

      - Does the extract process / extract file use column or row compression?


      Thanks much!