PL-300 Visualize and analyze the data Practice Test 13 — 15 Questions

Question 1

Which THREE actions can you take to improve the performance of a slow Power BI report that uses multiple visuals on a single page?

Accepted Answer

Use the Performance Analyzer to identify and optimize the slowest visuals.. Options B, D, and E are correct. Using Performance Analyzer (B) helps identify slow visuals and optimize them. Reducing the number of fields in each visual (D) reduces data retrieval and improves rendering. Disabling cross-filtering between unrelated visuals (E) reduces query load. Options A and C are incorrect: increasing data refresh frequency does not affect report rendering performance, and adding more calculated measures increases calculation load, potentially slowing performance.

Answer

Increase the frequency of data refreshes to reduce data latency.

Answer

Add more calculated measures to precompute aggregations.

Question 2

Which TWO DAX functions can be used to create a dynamic title that shows the currently selected year in a report, assuming a date table with a Year column?

Accepted Answer

CONCATENATEX(VALUES('Date'[Year]), 'Date'[Year], ", "). The correct answers are C and D. SELECTEDVALUE('Date'[Year]) returns the single selected year from a slicer or filter; if multiple years are selected, it returns blank (or a default value if provided). CONCATENATEX(VALUES('Date'[Year]), 'Date'[Year], ", ") concatenates all selected years into a comma-separated string, making it suitable for dynamic titles when multiple years are selected. Option A (SUM) is incorrect because it performs mathematical aggregation, not text retrieval. Option B (DISTINCT) returns a table, not a scalar value, so it cannot be used directly in a title measure. Option E (CALCULATE(VALUES(...))) is invalid because VALUES returns a table, and CALCULATE requires a scalar expression.

Answer

SUM('Date'[Year])

Answer

DISTINCT('Date'[Year])

Answer

CALCULATE(VALUES('Date'[Year]))

Question 3

Which THREE steps are required to set up row-level security (RLS) in Power BI Desktop?

Accepted Answer

Use the View as Roles feature to test the security filters.. To set up row-level security (RLS) in Power BI Desktop, you must first create roles and define DAX filter expressions in the Manage Roles dialog (D). You can then use the 'View as Roles' feature to test the security filters before publishing (A). After publishing the report to the Power BI service, you assign users or groups to roles in the dataset settings (B). Option C is incorrect because an on-premises data gateway is not required for RLS; it is used for data refreshes from on-premises sources. Option E is incorrect because roles must be defined in Power BI Desktop before publishing, not after.

Answer

Install and configure an on-premises data gateway.

Answer

Publish the report to the Power BI service before defining roles.

Question 4

You are building a Power BI report for the HR department to analyze employee turnover. You have an Employee table with columns: EmployeeID, Name, Department, HireDate, TerminationDate (nullable). The report must include a measure that calculates the number of active employees as of the last day of each month. The data model also includes a Calendar table with a continuous date range. The measure must be accurate regardless of any slicer selections on the Calendar table. You need to write the DAX measure. Which measure should you use?

Accepted Answer

CALCULATE(COUNTROWS(Employee), Employee[HireDate] <= MAX('Calendar'[Date]), (Employee[TerminationDate] > MAX('Calendar'[Date]) || ISBLANK(Employee[TerminationDate]))). It uses CALCULATE with conditions that count employees hired on or before the last day of the month (MAX('Calendar'[Date])) and whose termination date is after that date or is blank. This pattern correctly respects the month-end filter context. Option A is wrong because it uses MIN instead of MAX, causing termination condition to use the first day of the month, which may include employees terminated during the month. Option C is incorrect because it uses SUMX without CALCULATE; if there is an active relationship between Calendar and Employee (e.g., on HireDate), the Employee table is pre-filtered by the Calendar context, so the measure only considers employees hired within the current month rather than all employees hired on or before the end of the month, leading to undercounting. Option D is wrong because it uses TODAY() instead of the calendar date, so it does not calculate month-end active employees and ignores the calendar filter.

Answer

CALCULATE(COUNTROWS(Employee), Employee[HireDate] <= MAX('Calendar'[Date]), Employee[TerminationDate] > MIN('Calendar'[Date]) || ISBLANK(Employee[TerminationDate]))

Answer

SUMX(Employee, IF(Employee[HireDate] <= MAX('Calendar'[Date]) && (Employee[TerminationDate] > MAX('Calendar'[Date]) || ISBLANK(Employee[TerminationDate])), 1, 0))

Answer

CALCULATE(COUNTROWS(Employee), Employee[HireDate] <= TODAY(), ISBLANK(Employee[TerminationDate]))

Question 5

You have a Power BI report that uses a live connection to an Azure Analysis Services tabular model. Users report that the report is slow to load. You need to improve performance without changing the data model. What should you do?

Accepted Answer

Implement report-level measures to pre-calculate complex aggregations.. Implementing report-level measures can reduce the number of queries sent to the server, improving performance. Option B is wrong because enabling 'Load to report' would import data, breaking the live connection requirement. Option C is wrong because reducing the number of relationships would alter the data model, which is not allowed. Option D is wrong because increasing the number of visuals on each page could degrade performance, not improve it.

Answer

Enable 'Load to report' on the dataset to import data into Power BI.

Answer

Reduce the number of relationships in the data model.

Answer

Increase the number of visuals on each report page to reduce the number of pages.

Question 6

You are designing a Power BI report for executive leadership. The report must display key performance indicators (KPIs) with current values and trend arrows. Which visual type should you use?

Accepted Answer

KPI visual. The KPI visual is specifically designed to show a current value, a status indicator (like trend arrow), and a goal. Option A is wrong because a table visual is for detailed data, not KPIs. Option B is wrong because a card visual only shows a single value without trend. Option D is wrong because a gauge visual shows progress toward a goal but not a trend arrow.

Answer

Table visual

Answer

Card visual

Answer

Gauge visual

Question 7

You have a Power BI report that uses a DirectQuery dataset from Azure Synapse Analytics. Users complain that applying a filter on a date slicer takes over 30 seconds. The underlying table contains 500 million rows. You need to improve slicer responsiveness. What should you do?

Accepted Answer

Create a date dimension table in the source and use it for the slicer.. Creating a date dimension table reduces the cardinality of the slicer column, improving performance of DirectQuery filters. A date dimension typically contains one row per date with a unique key, whereas the fact table may have many duplicate date values, causing the slicer filter to process millions of entries. Using a date dimension allows the slicer to filter on a small, indexed table, and then propagate the filter to the fact table more efficiently. Option B is incorrect because adding more visuals increases query load. Option A is incorrect because disabling cross-filtering does not reduce the amount of data the slicer must scan. Option D is incorrect because importing a single column into Power BI still requires the slicer to filter the large DirectQuery table, and hybrid tables can cause performance issues.

Answer

Disable cross-filtering between the slicer and other visuals.

Answer

Add more visuals to the page so the slicer filter is reused across visuals.

Answer

Import the date column into Power BI and use it for the slicer.

Question 8

Refer to the exhibit. You have a Power BI measure defined as shown. Users report that when they filter by region, the measure always shows sales for the North region regardless of the filter. What is the most likely cause?

Accepted Answer

The filter argument in CALCULATE overrides the existing filter context on Region.. The CALCULATE function includes a filter argument that overrides any existing filter context on the Region column. Option B is wrong because SUM does not ignore filters. Option C is wrong because the measure syntax is valid. Option D is wrong because the filter is on Region, not on the entire table.

Answer

The SUM function ignores filters applied to the Sales table.

Answer

The measure syntax is invalid and defaults to no filter.

Answer

The filter is applied to the entire Sales table, not just the Region column.

Question 9

You are creating a Power BI report and need to visualize the relationship between two numerical variables, such as sales amount and profit. Which visual type is most appropriate?

Accepted Answer

Scatter chart. (scatter chart) because scatter charts are specifically designed to display the relationship between two numerical variables by plotting data points on an X and Y axis. Option A (line chart) is typically used to show trends over time, not direct relationships between two numerical variables. Option B (stacked bar chart) is used to compare parts of a whole across categories, not for two-variable relationships. Option C (pie chart) shows proportions of a whole for a categorical variable, which is inappropriate for numerical correlation. Therefore, the scatter chart is the most appropriate choice.

Answer

Line chart

Answer

Stacked bar chart

Answer

Pie chart

Question 10

You have a Power BI report with a page that contains a matrix visual showing sales by year and quarter. Users want to be able to drill down from year to quarter and then drill up again. The matrix currently shows only year. What should you configure?

Accepted Answer

Add both Year and Quarter fields to the matrix rows and enable drill-down mode.. Enabling the drill-down mode and adding both Year and Quarter to the matrix rows allows users to drill down and up. Option A is wrong because enabling drill-down without adding Quarter to the rows won't allow drill-down. Option B is wrong because adding a drillthrough page is for navigating to a detail page, not for drilling down in the same visual. Option D is wrong because adding a hierarchy to the columns would affect column drill-down, not row drill-down.

Answer

Add a hierarchy to the matrix columns.

Answer

Enable the drill-down mode on the matrix visual.

Answer

Add a drillthrough page that filters by year.

Question 11

You have a Power BI dataset that contains a table with sales data and a separate date table. You need to create a measure that calculates the total sales for the previous month relative to the selected date. Which DAX function should you use?

Accepted Answer

PREVIOUSMONTH. PREVIOUSMONTH returns a table containing all dates from the previous month relative to the first date in the current filter context. This makes it ideal for calculating total sales for the previous month. Option A (SAMEPERIODLASTYEAR) is used for year-over-year comparisons, not previous month. Option B (DATEADD) can shift dates by a specified interval, but it requires a number of months to shift and is less specific; PREVIOUSMONTH is the dedicated function for this scenario. Option D (PARALLELPERIOD) returns a parallel period shifted by a given interval, but again, PREVIOUSMONTH is the most straightforward choice for exactly the previous month.

Answer

SAMEPERIODLASTYEAR

Answer

DATEADD

Answer

PARALLELPERIOD

Question 12

You have a Power BI report that includes a slicer for product category. Users want to select multiple categories and see the combined data. The slicer currently allows only single selection. What should you change?

Accepted Answer

Enable multi-select in the slicer formatting options.. Enabling multi-select in the slicer formatting options allows users to select multiple categories. Option A is wrong because changing the style to dropdown does not affect multi-select capability. Option B is wrong because the sync slicer pane is for syncing slicers across pages, not for enabling multi-select. Option C is wrong because adding a second slicer does not enable multi-select on the original slicer.

Answer

Change the slicer style to dropdown.

Answer

Use the sync slicer pane to replicate the slicer on other pages.

Answer

Add a second slicer for product category.

Question 13

You have a Power BI report that uses a composite model with a DirectQuery source from Azure SQL Database and an imported table from Excel. You need to ensure that when a user filters the imported table, the DirectQuery table is also filtered accordingly. What should you configure?

Accepted Answer

Set the relationship direction to filter the DirectQuery table from the imported table.. In a composite model with both DirectQuery and imported tables, setting the relationship direction to filter the DirectQuery table from the imported table allows cross-filtering. This is done by configuring the relationship properties in Power BI Desktop to set the cross-filter direction to 'Both' or 'Single' from the imported table to the DirectQuery table. This enables the imported table to filter the DirectQuery table even though they use different storage modes. Option B is wrong because bidirectional cross-filtering on relationships between DirectQuery and imported tables is not supported in composite models; the cross-filter direction must be set appropriately but not necessarily bidirectional. Option C is wrong because merging tables would alter the data model and is not required for filtering. Option D is wrong because a calculated column in the DirectQuery table referencing the imported table would not automatically propagate filters and may cause performance issues.

Answer

Merge the imported table into the DirectQuery source.

Answer

Enable bidirectional cross-filtering on the relationship between the tables.

Answer

Create a calculated column in the DirectQuery table that references the imported table.

Question 14

You are designing a Power BI report to analyze sales performance across multiple regions. The data includes a Date table with a Many-to-One relationship to Sales. You need to ensure that users can drill down from Year to Quarter to Month in a matrix visual. What must you configure on the Date table?

Accepted Answer

Mark the Date table as a date table. Marking the Date table as a date table (Option D) is correct because it enables Power BI to automatically create the built-in date hierarchy (Year, Quarter, Month) and support drill-down in visuals like matrix. Option A is wrong because the built-in date hierarchy is only automatically created when the table is marked as a date table, not by just using it. Option B is wrong because a relationship between Date and Sales is necessary for filtering but does not create hierarchies or enable drill-down. Option C is wrong because calculated columns are not required; the hierarchy is auto-generated from the single date column.

Answer

Use the built-in date hierarchy without marking the table

Answer

Create a relationship between Date and Sales on the Date column

Answer

Add calculated columns for Year, Quarter, and Month

Question 15

You have a Power BI report that uses DirectQuery to a SQL Server database. Users report that the report is slow when filtering by a slicer on a large dimension table. You need to improve performance without changing the data source. Which approach should you take?

Accepted Answer

Set 'Assume Referential Integrity' on the relationship between tables. Setting 'Assume Referential Integrity' allows Power BI to use more efficient queries (INNER JOIN instead of OUTER JOIN) when filtering, which improves performance. Option A is wrong because creating aggregation tables is not supported in DirectQuery for this scenario. Option B is wrong because changing the storage mode to Dual is not applicable to DirectQuery sources. Option D is wrong because reducing cardinality may affect accuracy and does not address the underlying query efficiency.

Answer

Create an aggregation table on the dimension

Answer

Change the storage mode of the dimension table to Dual

Answer

Reduce the cardinality of the slicer field by grouping values