Trivial queries not folding

Hi nicbi 

You can refer to this document: https://docs.microsoft.com/power-bi/connect-data/desktop-directquery-about#:~:text=TopN%20filters%3A%20Advanced,the%20returned%20results. It has explained this behavior as below.

TopN filters: Advanced filters can be defined to filter on only the top or bottom N values ranked by some measure. For example, filters can include the top 10 categories in the previous visual. This approach again results in two queries being sent to the underlying source. However, the first query will return all categories from the underlying source, and then the TopN are determined based on the returned results.

Best Regards,
Community Support Team _ Jing
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