PL-300 Visualize and analyze the data Practice Test 5 — 15 Questions

Question 1

You have a Power BI report that uses a composite model with both Import and DirectQuery sources. You need to ensure that a measure using SUMX performs well. What should you do?

Accepted Answer

Create a calculated column in the source system to pre-aggregate values. In a composite model with both Import and DirectQuery sources, using SUMX to iterate over a DirectQuery table can be slow because each row may trigger a query. Option C recommends creating a calculated column in the source system (such as a computed column in SQL) that stores pre-aggregated values. This moves the aggregation closer to the data source, reducing the iteration overhead in Power BI. For example, you could add a column to a dimension table that contains the sum of related transaction rows, so that the measure can simply reference that column instead of looping over the fact table. Options A and B are incorrect: disabling relationships breaks the model, and using CALCULATE does not address iteration. Option D is incorrect because replacing SUMX with SUM changes the calculation logic and may not yield the same result.

Answer

Disable relationships between tables

Answer

Use CALCULATE instead of SUMX

Answer

Replace SUMX with SUM and adjust the model

Question 2

You have a Power BI report that shows sales by region. The map visual displays regions with incorrect boundaries. What is the most likely cause?

Accepted Answer

Bing Maps geocoding inaccuracies.. Power BI map visuals rely on Bing Maps for geocoding, and inaccuracies in Bing Maps data can cause incorrect region boundaries. Option A is incorrect because the map visual is commonly used for geographic data and is not the source of boundary issues. Option B is incorrect because data refresh affects data values, not the underlying map boundaries. Option C is incorrect because overlapping labels are a display issue unrelated to boundary accuracy.

Answer

The map visual is not the best choice for the data.

Answer

The data source is not refreshed.

Answer

The map labels are overlapping.

Question 3

You need to create a measure that calculates the year-over-year growth of sales. Which DAX function should you use?

Accepted Answer

SAMEPERIODLASTYEAR. SAMEPERIODLASTYEAR (option B) returns the same period in the previous year, making it ideal for year-over-year growth calculations. DATEADD (option A) can shift by any interval but is not specifically designed for direct YoY comparison. PARALLELPERIOD (option C) shifts by a full period (e.g., full month), which may not align with the exact same days. PREVIOUSYEAR (option D) returns the entire previous year, not the corresponding period.

Answer

DATEADD

Answer

PARALLELPERIOD

Answer

PREVIOUSYEAR

Question 4

You are designing a report for executives. They need to see both high-level KPIs and the ability to drill down into details. Which approach should you recommend?

Accepted Answer

Use drillthrough pages to navigate from summary visuals to detail pages.. Drillthrough pages allow users to click on a high-level visual and see detailed data for that specific context, providing both a KPI summary and drill-down capability. Option A is incorrect because a single table visual with drill-down does not present high-level KPIs effectively. Option C is less optimal because bookmarks switch entire views rather than providing context-sensitive navigation from a visual. Option D is incorrect because tooltips show only limited details, not a full drilldown experience.

Answer

Place all data in a single table visual with drill-down capability.

Answer

Use bookmarks to switch between summary and detail views.

Answer

Use report page tooltips to show details on hover.

Question 5

You need to ensure that a Power BI report is accessible to users with visual impairments. Which feature should you configure?

Accepted Answer

Add alt text to each visual.. Power BI allows adding alt text to visuals, which screen readers can read, making the report accessible to users with visual impairments. Option A is incorrect because applying a high-contrast theme only adjusts colors for readability but does not provide textual descriptions for screen readers. Option B is incorrect because enabling data labels adds numeric values but does not provide descriptive text that screen readers can interpret. Option D is incorrect because custom tab order aids keyboard navigation but does not address visual impairments directly.

Answer

Apply a high-contrast theme.

Answer

Enable data labels on all visuals.

Answer

Set custom tab order for visuals.

Question 6

You have the DAX measure shown. The measure returns blank for some periods even though there are sales in the current period. What is the most likely cause?

Accepted Answer

The Date table does not contain all dates from the previous year.. The SAMEPERIODLASTYEAR time intelligence function requires a contiguous date table that includes all dates from the previous year. If the Date table is missing dates (e.g., weekends or holidays), SAMEPERIODLASTYEAR returns blank for those periods, even if sales exist in the current period. Option B is incorrect because the measure is inherently filtered by the current context through the SUMMARIZE or CALCULATE structure; the issue is not a filter context problem. Option C is incorrect because CurrentSales is evaluated within the current context and typically returns a value; the blank arises from PreviousSales. Option D is incorrect because DIVIDE handles division by zero gracefully and returns blank; the root cause is a missing previous-year date, not division by zero.

Answer

The measure is not properly filtered by the current context.

Answer

The variable CurrentSales is not evaluated correctly.

Answer

The DIVIDE function returns blank when denominator is zero.

Question 7

You are building a report that uses AI visuals from Power BI. You want to automatically detect outliers in sales data. Which visual should you use?

Accepted Answer

Key Influencers. The Key Influencers visual includes an 'Outliers' tab that automatically detects and displays outliers in the data. Option A is wrong because the Q&A visual is designed for natural language queries and does not perform outlier detection. Option C is wrong because Smart Narrative generates text summaries but does not identify outliers. Option D is wrong because the Decomposition Tree breaks down a measure into contributing factors but does not specifically highlight outliers.

Answer

Q&A visual

Answer

Smart Narrative

Answer

Decomposition Tree

Question 8

You have a Power BI report that uses a measure with a filter context. You want to override the filter context for a specific calculation. Which function should you use?

Accepted Answer

CALCULATE. CALCULATE is used to modify the filter context on a measure. Option A (ALL) removes filters from the context. Option B (FILTER) returns a table based on a filter condition, not directly used for measuring. Option D (VALUES) returns a distinct list of values from a column.

Answer

ALL

Answer

FILTER

Answer

VALUES

Question 9

Which TWO actions can improve the performance of a Power BI report that uses DirectQuery?

Accepted Answer

Push transformations to the data source.. To improve performance of a Power BI report using DirectQuery, push transformations to the data source (B) and reduce the number of columns in the query (C). Pushing transformations reduces the workload on Power BI and leverages the source database's processing power. Reducing columns minimizes data transfer and query complexity. Calculated columns (A) are evaluated row-by-row in DirectQuery and can be slower than measures. Bidirectional cross-filtering (D) and increasing cross-filter direction to both (E) add complexity and can degrade performance because they create additional query dependencies and reduce the ability to push computations to the source.

Answer

Create calculated columns instead of measures.

Answer

Use bidirectional cross-filtering.

Answer

Increase cross-filter direction to both.

Question 10

Which THREE features are available in Power BI to support natural language queries?

Accepted Answer

Suggested Questions. Options B, C, and D are correct. The Q&A visual allows natural language queries; Suggested Questions appear in the Q&A visual to guide users; and Synonyms for tables and columns help the Q&A engine understand business terms. Option A is incorrect because Key Influencers is an AI visual that explains drivers, not natural language queries. Option E is incorrect because Quick Measures create DAX measures, not natural language queries.

Answer

Key Influencers visual

Answer

Quick Measures

Question 11

You are reviewing a Power BI dataset schema. The Date column is used in time intelligence measures. What is missing from this schema?

Accepted Answer

There is no separate date table marked as a date table.. There is no separate date table marked as a date table. In Power BI, for time intelligence functions (like TOTALYTD, SAMEPERIODLASTYEAR) to work correctly, you need a separate date table that is marked as a date table and has a continuous date range. Without this, time intelligence measures may produce incorrect results. Option B is incorrect because the version is irrelevant to the issue. Option C is incorrect because the Amount column's data type (decimal or not) is not the problem. Option D is incorrect because the Date column's data type is not the primary concern; while using date only is recommended, the main missing piece is the separate date table.

Answer

The version should be 2.0.

Answer

The Amount column should be a decimal.

Answer

The data type for Date should be date instead of dateTime.

Question 12

You have the DAX expression shown. It is intended to sum sales for the West region using an inactive relationship. However, the result is incorrect. What is the issue?

Accepted Answer

There may be multiple inactive relationships between Sales and Date, causing ambiguity.. USERELATIONSHIP activates a relationship, but if there are multiple inactive relationships between the same tables, it might not pick the intended one. Option A is wrong because the syntax is correct. Option C is wrong because the filter is applied correctly. Option D is wrong because there is no ambiguity in the filter.

Answer

The USERELATIONSHIP function syntax is incorrect.

Answer

The filter on Region should be in a separate CALCULATE.

Answer

The column names are case-sensitive and don't match.

Question 13

You have the measure shown. You add it to a table visual alongside columns from a related table. The total is higher than expected. What is the most likely cause?

Accepted Answer

The visual is expanding the measure due to a many-to-one relationship.. When a measure that sums a column from a table (e.g., Sales) is placed in a visual with columns from a related table on the 'one' side of a many-to-one relationship, the measure is evaluated in the context of the 'many' side. This can cause the measure to be expanded (cross-filtered) across multiple rows, resulting in a total that is higher than expected. Option A is wrong because the granularity issue is due to the relationship, not a different summarization. Option B is wrong because the measure is not filtered by a slicer, but the inflation occurs regardless of slicers. Option D is wrong because SUMX would not inherently fix the expansion; the issue is relationship-based, not formula-based.

Answer

The Sales table is summarized at a different granularity.

Answer

The measure is not filtered by any slicer.

Answer

The measure should use SUMX instead of SUM.

Question 14

You are building a report to analyze sales performance by region. You need to allow users to dynamically switch between viewing data as a bar chart and a line chart without modifying the report page. Which feature should you use?

Accepted Answer

Use bookmarks with buttons to toggle between charts.. Bookmarks with buttons allow users to switch between visual states dynamically. Option B is wrong because a slicer filters data, not switches chart types. Option C is wrong because a custom visual would require additional development. Option D is wrong because a drillthrough page navigates to a different page.

Answer

Add a slicer that changes the chart type.

Answer

Use a custom visual with built-in toggle.

Answer

Create a drillthrough page for each chart type.

Question 15

Your report contains a measure that calculates year-over-year growth. Users report that the measure returns blank for months where sales data exists in the current year but not in the previous year. How should you modify the measure to return 100% growth in such cases?

Accepted Answer

Use COALESCE(previous year sales, 1) in the denominator. None of the provided options are correct. The correct measure to return 100% growth when the previous year sales are blank is: IF(ISBLANK(PreviousYearSales), 1, DIVIDE(CurrentYearSales - PreviousYearSales, PreviousYearSales)). This explicitly handles the blank case by returning 1 (representing 100% growth) and uses the standard growth formula otherwise. Option A is incorrect because COALESCE(PreviousYearSales, 1) in the denominator yields (CurrentYearSales - 1)/1, which only equals 100% when CurrentYearSales = 2. Option B is incorrect because setting the previous year sales to 0 causes division by zero. Option C is incorrect because DIVIDE with alternate result 0 returns 0 instead of 100%. Option D is irrelevant as SELECTEDVALUE does not handle blanks in this context.

Answer

Wrap the previous year sales in IF(ISBLANK(...), 0, ...)

Answer

Use DIVIDE(current, previous, 0)

Answer

Use SELECTEDVALUE to ignore blank years