Microsoft Power BI Data Analyst PL-300 Practice Test 14
Question 130
A Power BI report takes nine seconds to render and the team must find whether a specific visual or DAX query dominates the delay. Which Power BI or Power Query action BEST meets the stated requirement?
- Increase the font size of all cards and assume performance improves
- Disable all page slicers without timing each visual
- Publish the same report to another workspace without inspecting query timings
- Run Performance Analyzer and inspect visual duration and the captured DAX query
Explanation
Correct Answer
D:Performance Analyzer identifies expensive visual operations and supports targeted optimization This addresses the specific requirement: a Power BI report takes nine seconds to render and the team must find whether a specific visual or DAX query dominates the delay.
Incorrect Answers
A:Visual typography does not identify the slow query This alternative therefore fails an explicit scenario constraint.
B:Removing functionality before measurement can hide the real bottleneck This alternative therefore fails an explicit scenario constraint.
C:Workspace location alone does not diagnose the expensive visual This alternative therefore fails an explicit scenario constraint.
Question 131
Finance needs Gross Margin Percent and some filtered regions have zero revenue, so division errors must be handled intentionally. A pilot instead implemented the following proposed change: Use the raw slash operator with no zero-denominator policy. The business requirement was not met. Which technical limitation MOST DIRECTLY explains the result?
- An already evaluated measure is not a column to sum and row count is the wrong denominator
- DIVIDE safely handles a zero denominator and can return a deliberate alternate result
- Unprotected division can produce undesirable special results in zero-revenue contexts
- Inventing revenue changes the underlying financial data to mask a calculation edge case
Explanation
Correct Answer
C:Unprotected division can produce undesirable special results in zero-revenue contexts This specifically addresses the deployed or proposed alternative: Use the raw slash operator with no zero-denominator policy.
Incorrect Answers
A:An already evaluated measure is not a column to sum and row count is the wrong denominator That limitation applies to a different alternative (Use SUM([Gross Margin]) divided by row count), not the one here.
B:DIVIDE safely handles a zero denominator and can return a deliberate alternate result This supports the recommended design but does not diagnose why the specified alternative fails.
D:Inventing revenue changes the underlying financial data to mask a calculation edge case That limitation describes Replace missing revenue with a fixed 1 in the source, not the specified approach.
Question 132
A report needs to count unique customers making purchases even if a customer places multiple orders. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- A customer with three orders is counted once and slicers restrict the counted customers
- The measure changes after a slicer click, but the result has not been compared against known test rows
- The field uses the expected numeric format, but no zero-denominator or date-boundary case was tested
- The DAX expression parses and returns a number for one unfiltered report page
Explanation
Correct Answer
A:A customer with three orders is counted once and slicers restrict the counted customers This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
B:Reacting to a slicer does not establish the correct math or intended filter semantics.
C:Formatting and a normal case do not validate the edge condition the calculation is supposed to handle.
D:A valid DAX expression may still evaluate the wrong period, denominator or context under filters.
Question 133
A legacy model contains Sales related bidirectionally to both Geography and Customer, plus another path between Geography and Customer, producing ambiguous filter results. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- The relationship diagram displays a line between tables, but no matching-key uniqueness test has run
- Filtering one dimension gives an explainable, unique path to the Sales fact and expected totals
- One aggregate value is nonblank, but filtering has not been tested from each intended dimension
- The model saves successfully, but source keys and report totals have not been reconciled
Explanation
Correct Answer
B:Filtering one dimension gives an explainable, unique path to the Sales fact and expected totals This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
A:A visible relationship is not proof that the dimension key and relationship cardinality are valid.
C:An unfiltered total cannot establish that the model's date roles and cross-filter paths behave as specified.
D:Saving a model does not rule out duplicate dimension rows, ambiguous paths or fact multiplication.
Question 134
Sales has an active order-date relationship and an inactive ShipDate relationship to Date, and a measure must compute shipped revenue for the date slicer. A design reviewer proposes this alternative: Activate both date relationships at once as an unqualified permanent model change. Which objection BEST explains why it would not satisfy the stated requirement?
- Duplicating the date does not switch filter propagation to the shipping relationship
- Unqualified competing active paths can be ambiguous and do not isolate a shipped-sales measure
- USERELATIONSHIP activates the specified inactive relationship for the measure evaluation
- The active order-date relationship would continue controlling the slicer
Explanation
Correct Answer
B:Unqualified competing active paths can be ambiguous and do not isolate a shipped-sales measure This specifically addresses the deployed or proposed alternative: Activate both date relationships at once as an unqualified permanent model change.
Incorrect Answers
A:Duplicating the date does not switch filter propagation to the shipping relationship That limitation describes Add a calculated column containing Date[Date] on each fact row without using ShipDate, not the specified approach.
C:USERELATIONSHIP activates the specified inactive relationship for the measure evaluation This supports the recommended design but does not diagnose why the specified alternative fails.
D:The active order-date relationship would continue controlling the slicer That limitation applies to a different alternative (Use the original [Total Revenue] measure without modifiers), not the one here.
Question 135
Finance wants the cumulative revenue from the start of the year through each month of a report, resetting when the year changes. A pilot instead implemented the following proposed change: Use SAMEPERIODLASTYEAR alone. The business requirement was not met. Which technical limitation MOST DIRECTLY explains the result?
- Prior-year shifting retrieves another period, not the current year's cumulative amount
- Product ordering is unrelated to calendar year-to-date accumulation
- TOTALYTD accumulates the current year's revenue over successive dates
- An ordinary sum returns each selected period's revenue, not cumulative revenue to date
Explanation
Correct Answer
A:Prior-year shifting retrieves another period, not the current year's cumulative amount This specifically addresses the deployed or proposed alternative: Use SAMEPERIODLASTYEAR alone.
Incorrect Answers
B:Product ordering is unrelated to calendar year-to-date accumulation That limitation applies to a different alternative (Use a running total over Product ID), not the one here.
C:TOTALYTD accumulates the current year's revenue over successive dates This supports the recommended design but does not diagnose why the specified alternative fails.
D:An ordinary sum returns each selected period's revenue, not cumulative revenue to date That limitation describes Use SUM(Sales[SalesAmount]) without a cumulative date filter, not the specified approach.
Question 136
A model's bidirectional relationships create multiple filter routes and expensive queries across several fact tables. A pilot instead implemented the following proposed change: Set all cross-filter directions to Both. The business requirement was not met. Which technical limitation MOST DIRECTLY explains the result?
- Global bidirectionality creates more filter paths and can harm performance
- Directed dimension-to-fact filtering reduces unnecessary propagation and ambiguity
- Disconnecting necessary dimensions breaks normal filtering and measure logic
- Additional fact-to-fact routes can multiply ambiguity rather than fixing it
Explanation
Correct Answer
A:Global bidirectionality creates more filter paths and can harm performance This specifically addresses the deployed or proposed alternative: Set all cross-filter directions to Both.
Incorrect Answers
B:Directed dimension-to-fact filtering reduces unnecessary propagation and ambiguity This supports the recommended design but does not diagnose why the specified alternative fails.
C:Disconnecting necessary dimensions breaks normal filtering and measure logic That limitation applies to a different alternative (Remove all product relationships and use disconnected tables), not the one here.
D:Additional fact-to-fact routes can multiply ambiguity rather than fixing it That limitation describes Add extra many-to-many relationships between facts, not the specified approach.
Question 137
A financial report needs dynamic Margin Percent that changes when users slice by company and quarter. Which Power BI or Power Query action BEST meets the stated requirement?
- Create a static calculated column for company-wide margin percent
- Format the SalesAmount column as Percentage
- Create an explicit DAX measure using filter-context-aware aggregations
- Create a Power Query scalar parameter for the quarterly ratio
Explanation
Correct Answer
C:A measure recalculates under slicers, unlike a stored row value This addresses the specific requirement: a financial report needs dynamic Margin Percent that changes when users slice by company and quarter.
Incorrect Answers
A:A stored calculated column will not recompute a company-wide ratio for changing slicer selections This alternative therefore fails an explicit scenario constraint.
B:Formatting an amount cannot compute margin divided by revenue This alternative therefore fails an explicit scenario constraint.
D:A query parameter is not a filter-context-aware report calculation This alternative therefore fails an explicit scenario constraint.
Question 138
A legacy model contains Sales related bidirectionally to both Geography and Customer, plus another path between Geography and Customer, producing ambiguous filter results. A pilot instead implemented the following proposed change: Set every relationship to Both because more propagation always helps. The business requirement was not met. Which technical limitation MOST DIRECTLY explains the result?
- Inactive paths break normal dimension filters rather than resolving the model design
- Competing active paths do not automatically resolve ambiguity or produce intended results
- A clean star filter flow reduces ambiguous propagation paths and makes slicer behavior predictable
- Additional both-direction paths can increase ambiguity and affect performance
Explanation
Correct Answer
D:Additional both-direction paths can increase ambiguity and affect performance This specifically addresses the deployed or proposed alternative: Set every relationship to Both because more propagation always helps.
Incorrect Answers
A:Inactive paths break normal dimension filters rather than resolving the model design That limitation describes Turn every relationship inactive, not the specified approach.
B:Competing active paths do not automatically resolve ambiguity or produce intended results That limitation applies to a different alternative (Create multiple active alternate paths between the same tables), not the one here.
C:A clean star filter flow reduces ambiguous propagation paths and makes slicer behavior predictable This supports the recommended design but does not diagnose why the specified alternative fails.
Question 139
A Category dimension contains duplicate CategoryKey values due to source errors, and Power BI refuses to create the intended one-to-many relationship to Sales. Which Power BI or Power Query action BEST meets the stated requirement?
- Make CategoryKey unique by deleting repeated sales transaction lines
- Change cardinality to many-to-many and ignore the defective category data
- Deduplicate or repair the Category dimension using an authoritative unique key
- Use bidirectional filtering to resolve duplicate dimension keys
Explanation
Correct Answer
C:The one side of a relationship requires unique key values and a failed refresh can follow duplicates This addresses the specific requirement: a Category dimension contains duplicate CategoryKey values due to source errors, and Power BI refuses to create the intended one-to-many relationship to Sales.
Incorrect Answers
A:Fact records are allowed to share a dimension foreign key and should not be deleted This alternative therefore fails an explicit scenario constraint.
B:A many-to-many relationship hides a bad dimension grain and can distort aggregations This alternative therefore fails an explicit scenario constraint.
D:Filter direction does not make duplicate one-side keys unique This alternative therefore fails an explicit scenario constraint.
Question 140
A report must calculate actual average item price across mixed sales quantities, weighted by units sold rather than average invoice price. Which Power BI or Power Query action BEST meets the stated requirement?
- Use SUM(Sales[UnitPrice]) as average price
- Use DIVIDE(SUMX(Sales, Sales[UnitPrice] * Sales[Quantity]), SUM(Sales[Quantity]))
- Use COUNTROWS(Sales) as the unit denominator
- Use AVERAGE(Sales[UnitPrice]) without quantity weights
Explanation
Correct Answer
B:SUMX aggregates line value and DIVIDE uses the correct units denominator for a weighted average This addresses the specific requirement: a report must calculate actual average item price across mixed sales quantities, weighted by units sold rather than average invoice price.
Incorrect Answers
A:Summing price values is not dividing by total units This alternative therefore fails an explicit scenario constraint.
C:Row counts can differ from total units sold across order lines This alternative therefore fails an explicit scenario constraint.
D:Simple averaging weights a one-unit item equally with a thousand-unit item This alternative therefore fails an explicit scenario constraint.