PL-300 Visualize and analyze the data Practice Test 8 — 15 Questions

Question 1

A user wants to see the top 10 products by sales but also include a total row at the bottom of the table. How can you achieve this?

Accepted Answer

Enable the total row in the formatting pane of the table visual. Enabling the total row in the formatting pane of a table visual adds a row that sums the sales values, including the total even when a Top N filter is applied to show only the top 10 products. Option A is incorrect because while Top N shows the top 10 products, it does not automatically include a total row; you must enable the total row separately. Option B is incorrect because 'Show items with no data' is unrelated to displaying totals. Option C is incorrect because using a separate card visual for total sales is an alternative approach but not the built-in table feature requested.

Answer

Apply a Top N filter to the visual and add a measure for total

Answer

Use the 'Show items with no data' option

Answer

Create a separate card visual for total sales

Question 2

You create a bar chart showing sales by product category. You want to sort the categories by total sales descending. What should you do?

Accepted Answer

Click the ellipsis menu on the visual and choose 'Sort by Sales' then 'Sort descending'. You can sort the visual by the Sales field in descending order. Option B is wrong because sorting by category name is alphabetical. Option C is wrong because the data model does not have a sort by column for this purpose. Option D is wrong because sorting by a measure is done via the visual's sort options.

Answer

Sort the visual by category name ascending

Answer

Create a measure that returns the sales value and sort by that measure

Answer

In the data model, set the Sort by Column property for Category

Question 3

Which TWO actions can improve the performance of a Power BI report that uses DirectQuery? (Select two.)

Accepted Answer

Set up aggregations in the data source. Options A and D are correct. Setting up aggregations in the data source reduces the amount of data queried, improving DirectQuery performance. Reducing the number of visuals on the page decreases the number of queries sent to the source. Option B is incorrect because calculated columns are evaluated row by row and can slow down performance in DirectQuery. Option C is incorrect because adding more slicers can increase the number of queries. Option E is incorrect because cache size does not affect DirectQuery, which queries the source each time.

Answer

Use calculated columns instead of measures

Answer

Add more slicers to allow users to filter data

Answer

Increase the cache size in the Power BI service

Question 4

Which THREE factors should you consider when designing a Power BI data model for a star schema? (Select three.)

Accepted Answer

Fact tables should contain numeric measures and foreign keys. Fact tables in a star schema store numeric, aggregatable measures (e.g., sales amount, quantity) and foreign keys that reference dimension tables. This structure enables efficient summarization and slicing by dimensions, which is a core requirement for Power BI performance and DAX calculations.

Answer

Use many-to-many relationships between dimensions

Answer

Dimension tables should be normalized to reduce redundancy

Question 5

Which TWO Power BI visuals can be used to display hierarchical data? (Select two.)

Accepted Answer

Decomposition tree. The Decomposition tree (C) is correct because it is a Power BI custom visual designed specifically for hierarchical data, allowing users to drill down into dimensions interactively. The Matrix (D) is correct because it supports hierarchical row and column headers, enabling multi-level grouping and expansion of data.

Answer

Scatter plot

Answer

Card

Answer

Pie chart

Question 6

Refer to the exhibit. The DAX query is executed in DAX Studio. It returns a table with Category and Total Sales. However, the total sales values are incorrect because they include all categories regardless of context. What is the most likely issue?

Accepted Answer

The relationship between Sales and Product is inactive. In DAX, SUMMARIZE creates filter context for the group-by columns. If the relationship between Sales and Product is active, the measure should evaluate per category. If the relationship is inactive, the filter on Product[Category] does not propagate to Sales, so SUM(Sales[Amount]) returns the grand total for each row, matching the symptom described.

Answer

The query does not filter by any specific context, so it returns grand total for each category

Answer

The SUMMARIZE function syntax is incorrect

Answer

The GROUP BY column should be from the Sales table

Question 7

Refer to the exhibit. This JSON defines a row-level security (RLS) role in Power BI. A user assigned to the 'Sales Manager' role runs a report that shows total sales across all regions. The sum displayed is lower than expected. What is the most likely reason?

Accepted Answer

The RLS filter restricts data to the West region only. The RLS role filters the Sales table to only show rows where Region is 'West', so the total sum only includes West region sales. Option A is wrong because the filter is applied regardless of the role's name. Option C is wrong because the sum is not a bug; it's the intended behavior. Option D is wrong because the user is in the role, so RLS is enforced.

Answer

The role name 'Sales Manager' does not match the user's job title

Answer

The user is not a member of the role

Answer

The FILTER function syntax is incorrect and causes an error

Question 8

You are a Power BI analyst at a retail company. The company has a SQL Server data warehouse with tables: 'Sales' (SalesID, ProductID, CustomerID, SalesDate, Amount, Quantity), 'Products' (ProductID, ProductName, Category, UnitPrice), 'Customers' (CustomerID, CustomerName, Region, Segment). The data warehouse is refreshed nightly. You need to build a Power BI solution that meets the following requirements:
- The report must be published to the Power BI service and support scheduled refresh.
- Users must be able to analyze sales by product category and customer region.
- The data model should follow a star schema design.
- A measure must calculate the running total of sales by date.
- The report must include a visual that shows the top 5 products by sales amount for the current year.
- Performance is critical; the report should load quickly.

You have imported the data into Power BI Desktop. Which of the following actions should you take to meet the requirements?

Accepted Answer

Create a date dimension table. Build a star schema with Sales as fact and Products, Customers, and Date as dimensions. Use TOTALYTD for running total and TOPN for top products.. Creating a date dimension table and building a star schema with Sales as fact and Products, Customers, and Date as dimensions is a best practice for performance and analytical needs. The TOTALYTD function efficiently calculates the running total of sales by date, and TOPN can be used to retrieve the top 5 products by sales amount for the current year. This approach supports scheduled refresh and efficient report loading. Option B is incorrect because using a calculated column with FILTER and EARLIER for running total is less efficient and not recommended for large datasets; also, a slicer alone does not dynamically filter for the current year across all visuals. Option C is incorrect because DirectQuery mode may lead to slower performance due to repeated queries to the data warehouse, especially for measures like running total that require complex calculations; it also does not support scheduled refresh effectively. Option D is incorrect because merging all tables into a single flat table violates star schema best practices, leads to data redundancy, and using EARLIER for running total in a measure (not possible; EARLIER is for calculated columns) is inefficient and can cause performance issues.

Answer

Import all tables. Create a calculated column for running total using FILTER and EARLIER. Use a slicer to filter by current year and sort a bar chart by sales.

Answer

Use DirectQuery mode to connect to the data warehouse. Write a SQL query for each visual to ensure real-time data. Use a SQL window function for running total.

Answer

Create a single flat table by merging all tables in Power Query. Use a measure for running total with EARLIER function. Create a Top N filter on a table visual.

Question 9

You need to design a report that allows users to drill from a yearly sales summary to quarterly details, then to monthly details, while maintaining the ability to go back. Which visual interaction should you enable?

Accepted Answer

Drill-down. Drill-down is the built-in Power BI feature that allows users to drill into hierarchical levels (e.g., from year to quarter to month) and use the back button to navigate up. Option A is wrong because bookmarks capture a specific state, not hierarchical drill. Option B is wrong because tooltips provide additional detail on hover, not drill-down within the same visual. Option D is wrong because drillthrough navigates to a separate page, not drill within the same visual hierarchy.

Answer

Bookmarks

Answer

Tooltips

Answer

Drillthrough

Question 10

You have a report page that shows sales by region. You want users to be able to select a region and see the corresponding sales details on the same page without navigating away. Which feature should you use?

Accepted Answer

Slicer. A slicer filters the entire page based on the selected value, showing details on the same page. Option B is wrong because drillthrough navigates to a different page. Option C is wrong because a matrix with expand/collapse is for hierarchical display, not cross-filtering. Option D is wrong because a card visual only shows a single value.

Answer

Drillthrough

Answer

Matrix with expand/collapse

Answer

Card visual

Question 11

You are building a report that uses a calculated column with the formula: 'Profit = Sales[Revenue] - Sales[Cost]'. Users report that the Profit column shows negative values for some rows when it should be positive due to a known data issue in the Cost column. What is the best approach to handle this without modifying the source data?

Accepted Answer

Modify the calculated column to use COALESCE or IF to treat missing or incorrect cost values.. Using DAX functions like IF or COALESCE within the calculated column allows you to handle missing or incorrect cost values by substituting a default or calculated value, thus correcting the profit without modifying the source data. Option A is wrong because filtering out negative profit rows removes data instead of fixing the underlying issue. Option B is wrong because conditional formatting only hides negative values visually; the incorrect values remain in the model. Option C is wrong because switching to DirectQuery mode does not address data quality issues and may introduce performance problems.

Answer

Create a measure that filters out rows with negative profit.

Answer

Apply conditional formatting on the Profit column to hide negative values.

Answer

Switch the table to DirectQuery mode to retrieve live data.

Question 12

You need to create a visualization that shows the contribution of each product category to total sales over time. Which chart type is most appropriate?

Accepted Answer

Stacked area chart. A stacked area chart is the most appropriate choice because it shows how each product category contributes to total sales over time, with the area between lines representing the proportion of each category. Clustered bar charts compare individual values but do not effectively depict contributions to a whole over time. Scatter plots show relationships between variables, not contributions. Pie charts display proportions at a single point in time, not over time.

Answer

Clustered bar chart

Answer

Scatter plot

Answer

Pie chart

Question 13

You have a report that contains a map visual showing sales by city. Several cities are missing from the map because the location data is ambiguous. What should you do to resolve this?

Accepted Answer

Create a calculated column that combines city and country to provide unambiguous location.. Creating a calculated column that combines city and country (or city and state) provides unambiguous location data, enabling the map visual to correctly place the cities. Option A is incorrect because adding latitude and longitude fields would also work, but it is not the simplest fix—it requires external data or additional calculations. Option C is incorrect because replacing the map with a table loses the geographic visualization and does not resolve the ambiguity. Option D is incorrect because adjusting bubble size only affects the visibility of data points, not the accuracy of their location.

Answer

Add latitude and longitude fields to the model.

Answer

Replace the map visual with a table.

Answer

Adjust the bubble size to make missing points visible.

Question 14

You are designing a report for mobile users. Which layout consideration is most important to ensure usability on small screens?

Accepted Answer

Use a vertical layout with key metrics placed at the top.. A vertical layout with key metrics at the top ensures that the most important information is immediately visible without scrolling, which is crucial for mobile usability. Option A is wrong because horizontal arrangement forces horizontal scrolling, which is inconvenient on small screens. Option B is wrong because placing all visuals on a single page can lead to an overwhelming experience and excessive vertical scrolling. Option D is wrong because while tooltips can provide additional details, they are not the primary layout consideration for mobile usability.

Answer

Arrange visuals horizontally to use screen width.

Answer

Place all visuals on a single page to avoid page navigation.

Answer

Use tooltips to provide additional details on tap.

Question 15

You want to allow users to filter a report by a specific date range (e.g., last 30 days) without requiring manual selection. Which approach should you take?

Accepted Answer

Add a relative date slicer to the report page.. A relative date slicer allows users to select predefined dynamic ranges like 'last 30 days' without manual date picking. Option A is incorrect because bookmarks capture a static state and require manual switching. Option C is incorrect because a calculated column is static and not user-interactive. Option D is incorrect because a filter in the Filters pane is static unless manually changed.

Answer

Use bookmarks to switch between fixed date ranges.

Answer

Create a calculated column that flags rows within the last 30 days.

Answer

Apply a filter on the date field in the Filters pane.