Limit/Expand Number of Rows in Your Visual



Adding a measure from any unrelated table to a Power BI visual with data from another table will cause Power BI to perform a cross-join returning all combinations of the dimension members. Say for example that you have last year SalesAmount on four different Product Subcategories, and these are the subcategories for which you want to plan / edit data (Plan Amount). Something like this:

When designing the visual, you can in design mode see the 'number of rows' returned by Power BI to the visual. When you add an unrelated measure such as the CurrentUserKey to the 'Aimplan User Key' value-field, you will see the number of rows grows exponentially.

Sometimes this is exactly what you want to achieve. You want the user to be able to forecast all product categories, not only the product categories with sales from last year or similar. But you should carefully consider how you decide to "push" rows to the users, both due to performance reasons, but also so that they actually plan on the rows they intend.

In the following chapters, you can read about how to limit, as well as expand, your cross-joins to generate the rows that the end-user will actually need.