2 Replies Latest reply on Nov 3, 2017 4:38 AM by Nick Corbin

    Apparent Duplicate Historical Events in Postgres Data

    Nick Corbin

      Hi, i'm creating some custom views with the Postgres data but struggling to understand what some of it means.


      For example I want to look the number of times a data source is accessed so I create a view based on joining hist_datasources and historical_event_types to historical_events on hist_datasource_id=hist_datasources_id and historical_event_type_id=type_id respectively. When I look at just Name = Access Data Source from historical_event_types I get multiple events all created at the same time for the same datasource but each with a different ID from historical_events. I don't really understand what these apparently duplicate events are.


      I've noticed the a similar thing with users and views - a user can have multiple Access View events for exactly the same time, the only difference between these multiple records being the ID.





        • 1. Re: Apparent Duplicate Historical Events in Postgres Data
          Matt Coles

          They're not really duplicates. I believe this is because there are multiple requests being sent to Data Server for a workbook that you've loaded that connects to the data source in question. Multiple connections can be created because you can run multiple instances of the Data Server processes on Server, and Tableau will generate multiple queries that run in parallel in order to generate the viz (or vizzes, if a dashboard), or load filter values, etc. I just loaded one of my own workbooks that points to a data source, and it connected to the same data source four times. The historical event Ids are different as you note, but also the worker name is differing in some of the requests I see (though, not necessarily).


          I'm less sure what a duplicate Access View record means...


          Anyway, in case you want to skip building the rest of the data source yourself, check out the TS Events data source at this post: Shareable Data Sources for Tableau Server . It might save you some time.

          1 of 1 people found this helpful
          • 2. Re: Apparent Duplicate Historical Events in Postgres Data
            Nick Corbin

            Thanks Matt, I realised you'd done some great work on the Postgres side of things (not quite how much though!) but i'd gone down the route of picking things apart myself to get a better understanding. I think it probably makes sense to use your shared data sources as the starting point so thanks for pointing me in their direction.