Dynamic RLS with USERNAME in Power BI - Dashboard Guide

Dashboard Mode - Dynamic RLS with USERNAME

Business Question

How can we show sales data only for the logged-in user using dynamic row-level security (RLS) with the USERNAME function?

Sample Data

UserEmail	Region	SalesAmount	OrderDate
[e-mail]	North	1000	2024-01-15
[e-mail]	South	1500	2024-02-20
[e-mail]	East	700	2024-03-05
[e-mail]	West	1200	2024-01-30
[e-mail]	North	900	2024-04-10

Dashboard Components

• KPI Card: Total Sales for Current User
  Formula:
  Total Sales = SUM(Sales[SalesAmount])
  Shows the sum of sales filtered by the logged-in user's email.
• Table: Sales Details
  Columns: UserEmail, Region, SalesAmount, OrderDate
  Shows only rows where UserEmail matches the logged-in user due to RLS.
• Bar Chart: Sales by Region for Current User
  X-axis: Region
  Y-axis: Sum of SalesAmount
  Filtered dynamically by RLS to show only current user's data.

RLS Role Filter Expression

Sales[UserEmail] = LOWER(USERNAME())

This expression filters the Sales table rows to only those where the UserEmail matches the logged-in user's email.

Dashboard Layout

+----------------------+----------------------+
|      KPI Card        |      Bar Chart       |
|  Total Sales Amount  | Sales by Region      |
+----------------------+----------------------+
|                  Sales Details Table             |
+-------------------------------------------------+

Interactivity

The dynamic RLS filter automatically applies based on the logged-in user's email. No manual slicers are needed to filter data by user.

All visuals (KPI card, bar chart, and table) update automatically to show only data for the current user.

Self Check

If you log in as [e-mail], which rows appear in the Sales Details table?

Answer: Only rows where UserEmail is [e-mail] (rows 2 and 5 from the sample data).

All visuals update to show sales totals and regions only for Bob's data.

Key Result

Dashboard showing sales data filtered dynamically by logged-in user using USERNAME-based RLS.

Practice

1. What is the main purpose of using USERNAME() in Dynamic Row-Level Security (RLS) in Power BI?

easy

A. To change the report theme dynamically

B. To filter data based on the logged-in user's identity

C. To calculate the total sales amount

D. To create new columns in the data model

Solution

1. Step 1: Understand USERNAME() function

   The USERNAME() function returns the current logged-in user's email or username.

2. Step 2: Apply USERNAME() in Dynamic RLS

   Dynamic RLS uses USERNAME() to filter data so each user sees only their allowed rows.

3. Final Answer:

   To filter data based on the logged-in user's identity -> Option B

4. Quick Check:

   USERNAME() filters data by user [OK]

Hint: USERNAME() filters data by current user identity [OK]

Common Mistakes:

• Thinking USERNAME() creates new columns
• Using USERNAME() to calculate totals
• Confusing USERNAME() with theme settings

2. Which of the following is the correct syntax to create a filter rule for Dynamic RLS using USERNAME() in Power BI?

easy

A. [UserEmail] = USERNAME()

B. FILTER([UserEmail], USERNAME())

C. USERNAME() = [UserEmail]

D. CALCULATE(USERNAME(), [UserEmail])

Solution

1. Step 1: Understand filter rule syntax

   In Dynamic RLS, the filter rule compares a column to the current user using =.

2. Step 2: Identify correct syntax

   The correct syntax is [UserEmail] = USERNAME() to filter rows matching the logged-in user.

3. Final Answer:

   [UserEmail] = USERNAME() -> Option A

4. Quick Check:

   Filter rule uses column = USERNAME() [OK]

Hint: Use column = USERNAME() for filter rules [OK]

Common Mistakes:

• Using USERNAME() on left side of comparison
• Using FILTER() function incorrectly
• Trying to CALCULATE USERNAME()

3. Given a table with a column UserEmail and a Dynamic RLS filter rule [UserEmail] = USERNAME(), what data will a user with email [e-mail] see?

medium

A. Only rows where UserEmail is not [e-mail]

B. All rows regardless of UserEmail

C. Only rows where UserEmail is [e-mail]

D. No rows at all

Solution

1. Step 1: Understand the filter rule effect

   The rule [UserEmail] = USERNAME() filters rows to only those matching the logged-in user's email.

2. Step 2: Apply to user email

   For user [e-mail], only rows with UserEmail = [e-mail] are visible.

3. Final Answer:

   Only rows where UserEmail is [e-mail] -> Option C

4. Quick Check:

   Filter shows rows matching USERNAME() [OK]

Hint: User sees only rows matching their email [OK]

Common Mistakes:

• Assuming user sees all rows
• Thinking user sees rows with different emails
• Believing no rows are shown

4. You wrote this RLS filter rule: FILTER(Users, Users[Email] = USERNAME()). Why does it cause an error in Power BI?

medium

A. FILTER cannot be used directly as a filter rule; it expects a boolean expression

B. USERNAME() is not allowed in RLS rules

C. The column name should be lowercase

D. FILTER requires two arguments

Solution

1. Step 1: Understand RLS filter rule requirements

   RLS filter rules expect a boolean expression, not a table expression like FILTER().

2. Step 2: Identify the error cause

   Using FILTER() returns a table, causing a syntax error in RLS rules.

3. Final Answer:

   FILTER cannot be used directly as a filter rule; it expects a boolean expression -> Option A

4. Quick Check:

   RLS rules need boolean expressions [OK]

Hint: Use boolean expressions, not FILTER(), in RLS rules [OK]

Common Mistakes:

• Using FILTER() instead of boolean condition
• Thinking USERNAME() is disallowed
• Assuming column case matters
• Believing FILTER needs two arguments

5. You want to create Dynamic RLS so that managers see data for their team members, and team members see only their own data. The table has columns UserEmail and ManagerEmail. Which DAX filter rule correctly implements this?

hard

A. USERNAME() = [UserEmail] && USERNAME() = [ManagerEmail]

B. [UserEmail] = USERNAME() && [ManagerEmail] = USERNAME()

C. FILTER(Users, [UserEmail] = USERNAME() || [ManagerEmail] = USERNAME())

D. [UserEmail] = USERNAME() || [ManagerEmail] = USERNAME()

Solution

1. Step 1: Understand the requirement

   Managers should see rows where they are the manager, and users see their own rows.

2. Step 2: Choose correct logical operator

   Use OR (||) to allow either condition: user is the row owner or user is the manager.

3. Step 3: Validate syntax

   [UserEmail] = USERNAME() || [ManagerEmail] = USERNAME() uses correct syntax and logic: [UserEmail] = USERNAME() || [ManagerEmail] = USERNAME().

4. Final Answer:

   [UserEmail] = USERNAME() || [ManagerEmail] = USERNAME() -> Option D

5. Quick Check:

   Use OR (||) to combine user and manager filters [OK]

Hint: Use OR (||) to combine user and manager filters [OK]

Common Mistakes:

• Using AND (&&) instead of OR (||)
• Reversing USERNAME() and column order
• Using FILTER() in RLS rule