BUG: Power BI table relationships don't work the same from direct queries as loaded data

[sjexpressmed]

I have a power bi report that loads data on a schedule and links that list of products in a one to many relationship to a product list pulled from an excel document in sharepoint.  Some of the products loaded with the sql query don't exist in the excel document so they show up in the slicer as having a (Blank) product category (pulled from the excel document) and the list of products in the document being grouped on product and category, shows the first item with a blank group at the top of the list.

Unfortunately people don't view that report often and it eventually stops refreshing the data on a daily basis, so I had the bright idea of rewriting it to use live data from a direct query.

I added the new query, swapped out all the fields in the grid and the slicers, deleted the old table from the model, went into relationships and joined it up exactly the way the older report was joined (I kept the two reports open side by side to make sure). 

And I found none of the blank category products were displayed in the slicer or in the grid, but oddly, the quantities did show up in the grand total at the bottom of the grid as the column totals and grand total at the bottom of the report was the same between the two reports despite the missing rows.

Its almost as if the relationship in loaded data was a left join, but when loading the data in a direct query, it was an inner join.  Though I can't explain how the totals still showed the correct total of products.