The correct answer is to use the existing measure and add a visual-level filter to show percentage. This is because a live connection to Analysis Services prevents you from modifying or creating new measures in Power BI; you must work with the pre-existing measures from the tabular model. By applying the 'Show value as' option set to 'Percent of grand total' on the visual, you override the region filter context without altering the underlying ALL function measure, achieving the percentage of total with live connection to Analysis Services. On the PL-300 exam, this scenario tests your understanding of live connection limitations versus import mode, often appearing as a trap where candidates incorrectly try to create a new DAX measure. The key memory tip is: live connection means you can only change how a measure is displayed, not what it calculates.
PL-300 Prepare the data Practice Question
This PL-300 practice question tests your understanding of prepare the data. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
You have a Power BI dataset that uses a live connection to an Analysis Services tabular model. The model contains a measure that uses the ALL function. You need to create a report page that shows sales by region, but you want to display the percentage of total sales regardless of region filter. How should you achieve this?
Modify the measure in the Analysis Services model to use ALLSELECTED instead of ALL.
Why wrong: You cannot modify the model from Power BI Desktop.
B
Use the existing measure and add a visual-level filter to show percentage.
Visual-level filters can be applied, but for percentage of total, you need a measure that uses ALL; you must request the model owner to create a percentage measure.
C
Change the connection to Import mode and then create the measure.
Why wrong: This changes the connection type and loses the benefits of live connection.
D
Create a new measure in the Power BI dataset using DAX that divides the region sales by total sales.
Why wrong: Measures cannot be added to a live connection dataset.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Use the existing measure and add a visual-level filter to show percentage.
Option B is correct because with a live connection to Analysis Services, you cannot modify the underlying measure in Power BI; you must work with the existing measures. By using the existing measure and adding a visual-level filter to show the percentage (e.g., by using the 'Show value as' option set to 'Percent of grand total'), you can display the percentage of total sales regardless of the region filter without altering the model.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Modify the measure in the Analysis Services model to use ALLSELECTED instead of ALL.
Why it's wrong here
You cannot modify the model from Power BI Desktop.
✓
Use the existing measure and add a visual-level filter to show percentage.
Why this is correct
Visual-level filters can be applied, but for percentage of total, you need a measure that uses ALL; you must request the model owner to create a percentage measure.
Related concept
Read the scenario before looking for a memorised answer.
✗
Change the connection to Import mode and then create the measure.
Why it's wrong here
This changes the connection type and loses the benefits of live connection.
✗
Create a new measure in the Power BI dataset using DAX that divides the region sales by total sales.
Why it's wrong here
Measures cannot be added to a live connection dataset.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often think they need to modify the measure or change the connection mode to achieve percentage calculations, but Power BI's visual-level formatting options can handle this without altering the source model.
Detailed technical explanation
How to think about this question
When using a live connection to Analysis Services, Power BI acts as a client and cannot modify or add measures to the source model. The 'Show value as' feature in Power BI visuals allows you to calculate percentages like 'Percent of grand total' without altering the underlying DAX measure, leveraging the visual-level filter context to compute the ratio dynamically. This approach respects the ALL function in the original measure while still providing the desired percentage calculation.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Prepare the data — This question tests Prepare the data — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Use the existing measure and add a visual-level filter to show percentage. — Option B is correct because with a live connection to Analysis Services, you cannot modify the underlying measure in Power BI; you must work with the existing measures. By using the existing measure and adding a visual-level filter to show the percentage (e.g., by using the 'Show value as' option set to 'Percent of grand total'), you can display the percentage of total sales regardless of the region filter without altering the model.
What should I do if I get this PL-300 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This PL-300 practice question is part of Courseiva's free Microsoft certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PL-300 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.