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Mr_Robot0092's avatar
Mr_Robot0092
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9 months ago
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DAX query with SUMMARIZECOLUMNS - Optimization

Hi everyone, I’m facing a critical performance issue in Power BI when running an advanced DAX query used by a paginated report. The query operates over a large fact table (~131 million rows) and pro...
  • v-kpoloju-msft's avatar
    9 months ago

    Hi Mr_Robot0092,

    Thank you for reaching out to the Microsoft Fabric Community Forum. Also, thanks to amitchandak, for his inputs on this thread.

    Thanks for confirming and for testing that. Just to clarify the syntax issue you are seeing with FILTER() inside SUMMARIZECOLUMNS is expected. The function doesn’t allow filters in that position, which is why it errors out.

    However, even if the syntax was adjusted, it unfortunately wouldn’t resolve the original memory issue. The error you are facing is caused by the size of the intermediate tables this query generates, combined with the full outer join in DAX. That is what triggers the Resource Governance limit.

    The best approach here is still to move the heavy transformations (joins, merging, grouping, filtering) out of DAX and into Power Query / SQL / Warehouse and only return the required dataset to the report. That is what will avoid the memory limitation completely.

    Refer this link: https://learn.microsoft.com/en-us/dax/summarizecolumns-function-dax 

    Hope this clears it up. Let us know if you have any doubts regarding this. We will be happy to help.

    Thank you for using the Microsoft Fabric Community Forum.