3 Replies Latest reply on Jul 17, 2015 9:48 AM by Jeff D

    Calculated columns de-materialize on server

    Robin Schouten van der Velden



      Someone suggested that this question had to be asked on the server admin forum.


      I've got issues with some workbooks on server (8.3.3) which have extract in them made from Tableau published data sources. The workbooks themselves have been made on desktop, but have been created in and migrated from Tableau 8.1 desktop and server.


      The workbooks have some expensive string calculation in them to resegment the data. Ideally this would have been done in the data source, but this was working fine on desktop and server as the calculations were materialized in the extract, until the extract is refreshed on server. All of a sudden the workbook takes minutes to load. When I download the workbook, optimise the extract and reupload, it works fine until the extract is refreshed.


      I can see from the performance monitoring on server that initially the workbook take 5 secs to load with nothing significantly , but after the refresh all these string calculations are suddenly back and taking up a lot of time, suggesting that they have been 'dematerialised'.


      Does anyone know what is causing this behaviour? I've tried deleting the extracts and retaking them, making sure the extract filter don't rely on calculated fields and that doesn't help, but it seems that completely rebuilding the workbook from scratch and retaking the extracts works. Unfortunately, that means rebuilding a number of quite complex workbooks from scratch.


      Many thanks