A DAX measure 'Total Sales' is used in a visual that filters by year and region. The visual is slow. You use Performance Analyzer and copy the DAX query to DAX Studio. In DAX Studio, you see that the query scans a large table with many columns. What should you do to reduce the query time?

Change the measure to use a calculated column instead of a measure.

Use a visual-level filter to limit the number of rows returned.

Remove unused columns from the table to reduce the storage engine scan size.

Add more rows to the table to increase the scan speed.

A telecommunications company imports a call detail record (CDR) table that includes both successful and failed calls. The report only needs to show successful calls. The table also includes a 'CallDuration' column that is used only for failed calls. The model is large and slow to refresh. What should you do to improve performance?

Use a row-level security (RLS) rule to show only successful calls to all users.

Filter the CDR table to only successful calls during import, and remove the 'CallDuration' column if it is not needed for successful calls.

Import all calls and use a calculated column to flag successful calls.

Keep all calls but remove the 'CallDuration' column and create a measure that filters to successful calls.

A data model contains a table of sales transactions. The report only analyzes transactions from the current fiscal year, but the table includes historical rows from previous years. Which action would most directly improve model performance by reducing unnecessary rows?

Filter the table to retain only rows from the current fiscal year.

Change the table's storage mode to DirectQuery.

Apply a visual-level filter to the report page.

Create a calculated column that flags rows from the current fiscal year.

A logistics company imports a table with one row per GPS ping for every vehicle, recorded every 10 seconds. The report only needs to show daily distance traveled per vehicle and per route. The table also contains a 'DriverName' column that is not used in any report. The model is large and slow to refresh. What should you do to reduce the model size while still supporting the required reports?

Aggregate the GPS data to daily totals per vehicle and route before importing, and exclude the 'DriverName' column.

Import the raw GPS data and use a calculated table to summarize daily totals per vehicle and route.

Use a row-level security (RLS) rule to limit the GPS data to only the current day for all users.

Keep the raw GPS data but remove the 'DriverName' column and create a measure that calculates daily distance.

In Power BI Desktop, which tool is specifically designed to measure the time it takes to refresh, process, and render visuals, and to identify which elements are slow?

Data Analysis Expressions (DAX) Studio

Microsoft Certified:Power BI Data Analyst Associate

Domain 2Objective 3

Optimize Model Performance PL-300 Practice Questions (Page 6)

Part of the Model the data domain, which accounts for 25–30% of the PL-300 exam. Microsoft does not publish an official question count, but from its 100-minute exam (~40–65 total, ~10–20 in this domain), expect 3–7 from this objective — we provide 35 practice questions to prepare you well beyond it. (estimate)

35questions here

7free pages

5concepts

25–30%of the exam

Questions 26–30

26application · medium
A DAX measure 'Total Sales' is used in a visual that filters by year and region. The visual is slow. You use Performance Analyzer and copy the DAX query to DAX Studio. In DAX Studio, you see that the query scans a large table with many columns. What should you do to reduce the query time?
Select an answer first
27application · medium
A telecommunications company imports a call detail record (CDR) table that includes both successful and failed calls. The report only needs to show successful calls. The table also includes a 'CallDuration' column that is used only for failed calls. The model is large and slow to refresh. What should you do to improve performance?
Select an answer first
28foundation · easy
A data model contains a table of sales transactions. The report only analyzes transactions from the current fiscal year, but the table includes historical rows from previous years. Which action would most directly improve model performance by reducing unnecessary rows?
Select an answer first
29application · medium
A logistics company imports a table with one row per GPS ping for every vehicle, recorded every 10 seconds. The report only needs to show daily distance traveled per vehicle and per route. The table also contains a 'DriverName' column that is not used in any report. The model is large and slow to refresh. What should you do to reduce the model size while still supporting the required reports?
Select an answer first
30foundation · easy
In Power BI Desktop, which tool is specifically designed to measure the time it takes to refresh, process, and render visuals, and to identify which elements are slow?
Select an answer first

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Optimize Model Performance PL-300 Practice Questions (Page 6)

Questions 26–30

A DAX measure 'Total Sales' is used in a visual that filters by year and region. The visual is slow. You use Performance Analyzer and copy the DAX query to DAX Studio. In DAX Studio, you see that the query scans a large table with many columns. What should you do to reduce the query time?

A data model contains a table of sales transactions. The report only analyzes transactions from the current fiscal year, but the table includes historical rows from previous years. Which action would most directly improve model performance by reducing unnecessary rows?

In Power BI Desktop, which tool is specifically designed to measure the time it takes to refresh, process, and render visuals, and to identify which elements are slow?

Keep studying — Model the data