Introduction to row-level security (RLS)
With row-level security (RLS), you can restrict users from seeing all data that is in a Power BI model. RLS is the main form of security in a Power BI model. It is called row-level because you define which rows in each table in the model are visible to the user. Note that because RLS is set on the model level, any report that visualizes results from that model will satisfy the security policy defined on it.
Before diving in, let's make something clear: when you need a secure solution, you have to use RLS (or a related concept called object-level security, which we will discuss later in this chapter). There's just no way around it. Do not try to implement security through sharing reports (or not sharing, rather). You cannot oversee what will happen to the use of your model in the future: people may get self-service access to the Power BI model, get added to security groups by accident, or other things may happen. For the same reason...