What is RLS in Power BI: Definition and Usage

Row-Level Security (RLS) in Power BI is a feature that restricts data access for users based on filters you define. It ensures each user sees only the data they are allowed to see by applying rules at the row level in your data model.

How It Works

Row-Level Security (RLS) works like a filter that controls what data each user can see in a Power BI report. Imagine a company where sales managers should only see sales data for their own region. RLS applies rules that limit the data rows visible to each manager based on their region.

Technically, you create roles with filter rules in Power BI Desktop. When a user opens the report, Power BI checks their role and applies the filters automatically. This way, users only see the data allowed by their role, without changing the report itself.

Example

This example shows how to create a simple RLS role that filters data by a 'Region' column.

DAX

DEFINE ROLE [SalesRegionRole] AS
FILTER('Sales', 'Sales'[Region] = USERNAME())

Output

When a user with username 'north' views the report, they only see sales rows where 'Region' equals 'north'.

When to Use

Use RLS when you want to share the same Power BI report with multiple users but restrict their data access based on their identity or role. Common cases include:

• Sales teams seeing only their own territory's data.
• HR viewing employee data limited to their department.
• Financial reports showing data by cost center or region.

RLS helps maintain data privacy and security without creating multiple reports.

Key Points

• RLS filters data at the row level based on user roles.
• Roles and filters are defined in Power BI Desktop using DAX expressions.
• RLS works with Power BI Service when reports are shared.
• It helps enforce data security and privacy.
• Users only see data allowed by their assigned roles.

Key Takeaways

Row-Level Security (RLS) restricts data access in Power BI reports by filtering rows based on user roles.

You define RLS roles and filters using DAX expressions in Power BI Desktop.

RLS is essential for sharing reports securely with different users seeing only their permitted data.

It helps maintain data privacy without duplicating reports for each user group.