In Power BI,
understanding how filters flow between tables is key to building effective data
models. By default, relationships are set to allow filters to move in just one
direction—usually from a dimension table to a fact table. This is known as a
single-direction filter. However, in some scenarios, it’s useful to enable
filters to flow both ways between tables. This is called a bi-directional
filter.
To make this
clearer, let’s look at an example.