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Anonymous's avatar
Anonymous
Not applicable
10 years ago

Each data refresh gives different data results

Hello, I created a .PBIX file with a model and it has been working correctly for 3 months. Data sources are SQL Server 2014 and some Excel worksheets. After updating Power BI Desktop to the lat...
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InaNortje's avatar
InaNortje
Advocate I
9 years ago

Hi v-micsh-msft

 

I seem to have a very similar issue as posted here.

SQL 2016 and Excel data sources.  Every time I refresh, I get a different result set appearing on my reports.  Some rows are missing, others seem to be duplicated.  Each refresh yields a slightly different result set, and each time it is incorrect.  

 

I created the model and handed over to a business user late November 2016 year.  About 2 weeks ago the user reported that some historical results kept changing.  I am not sure at which point exactly this issue started, but I am now troubleshooting the issue on Power BI Desktop version 2.42.4611.701 64-bit (January 2017), and getting this strange behaviour consistently.  The user reporting the issue is running the November release, so it seems to be across different versions of PBI Desktop.

 

Can I go ahead and add to this post, or should I open another thread?  I have the trace logs ready.

 

Regards

 

Ina

lizrowden's avatar
lizrowden
Helper I
9 years ago

I am also having issue. Has anyone found the cause or a solution? I am on the latest version of the Power Bi desktop. The data in the query editor is fine and the same number of rows are returned, but everytime I click the Refresh button on the report I get a different result even though the underlying data and report has not changed.

  • Anonymous's avatar
    Anonymous
    Not applicable
    8 years ago

    This is indeed really annoying, I am facing same problem since last three day every single time I refresh it gives me different results L I am using Power Bi latest release September. Also using SQl Server 2012, I tried using SQL Server 2016 No change in behavior. Can someone please respond

    • InaNortje's avatar
      InaNortje
      Advocate I
      8 years ago

      Hi Anonymous

       

      Add an "order by" clause to the source query - that solved the problem for me.  The issue only starts once the data volumes get really high.  Power BI seems to run the query twice, getting the first x rows in query 1, and then total-x rows in query 2.  It assumes that the order is the same, and then you get some duplicates and some missing records.

       

      Let me know if that works for you too.

       

      Thanks

       

      Ina

       

       

      • InaNortje's avatar
        InaNortje
        Advocate I
        8 years ago

        Hi lizrowden, Anonymous

         

        Below is a link describing the full details of the issue that I had, and how I finally resolved it. 

        The conditions under which it occurred are:

         - High volume source data 

         - Subsequent merge

        (note: the query doesn't neccessarily have to return high volume data.  It's the source table size that seems to determine this)

         

        https://community.powerbi.com/t5/Issues/Power-Query-Merge-yields-inconsistent-results/idi-p/119485

         

        The easiest fix was to add an explicit "order by" clause to my source query.

         

        Hope this helps

         

        Ina