At the end of March, we released the second update of SQLBI+ with a new session about 
different types of many-to-many relationships in DAX.
The goal is to explain the difference between the many-to-many cardinality relationship available in Power BI (which is a specific relationship type), and the traditional concept of many-to-many relationships that exist between two business entities from a logical point of view – the latter is usually implemented through an additional bridge table containing the data to establish the connections between the different entities.
The session is an updated version of the content also published in the article, Relationships in Power BI and Tabular models.
Stay tuned for new SQLBI+ content coming in the next few months!