Microsoft PL-300 Practice Test 15
Question 140
The original scenario was: A sales table has many order lines per customer, and the team wants total revenue by CustomerID. The initial solution is already in place. Now this new requirement arises: The report later needs monthly customer totals. Which ADDITIONAL action BEST meets the changed condition?
- The grouped table's customer totals match independently calculated source sums
- Use Group By CustomerID with Sum over the sales amount
- Remove duplicate CustomerID rows and keep only the first sale
- Group by both CustomerID and Month rather than CustomerID alone
Explanation
Correct Answer
D:The changed requirement is 'The report later needs monthly customer totals'. The additional response is 'Group by both CustomerID and Month rather than CustomerID alone'.
Incorrect Answers
A:This observes the original approach but is not an additional action: The grouped table's customer totals match independently calculated source sums.
B:This is the already implemented original solution: Use Group By CustomerID with Sum over the sales amount. Power Query Group By aggregates multiple rows into a specified grain. It does not itself solve the new requirement.
C:This remains unsuitable for the original situation: Deduplication discards valid transactions instead of summing them. It also does not meet the changed need.
Question 141
Quarterly sales CSV files have the same column layout and should form one continuous fact table. Which approach BEST meets the stated Microsoft Power BI requirement?
- Merge the quarterly datasets on row index
- Append the quarterly queries into one transaction table
- Replace or map Y and N to True and False and assign Logical type
- Align the schemas explicitly before appending the changed file
Explanation
Correct Answer
B:Append stacks compatible row sets rather than joining them horizontally. For the stated case, Append the quarterly queries into one transaction table.
Incorrect Answers
A:Joining by position can corrupt transactions and does not combine sequential periods. The proposed shortcut 'Merge the quarterly datasets on row index' fails the documented need.
C:This addresses a separate source situation: An old application exports OrderFlag values Y and N, while a new semantic model needs true Boolean values. It does not directly satisfy this case's priority.
D:This might be appropriate after a different requirement arises: The next quarter introduces a new optional column. It is not the best initial response to the stated case.
Question 142
Quarterly sales CSV files have the same column layout and should form one continuous fact table. A colleague proposes: Merge the quarterly datasets on row index. Which explanation BEST identifies the defect in that proposal?
- Currency is not an appropriate Boolean type
- Joining by position can corrupt transactions and does not combine sequential periods
- The suggested approach is safe merely because its product name is familiar.
- Append stacks compatible row sets rather than joining them horizontally
Explanation
Correct Answer
B:Joining by position can corrupt transactions and does not combine sequential periods. This directly explains why the proposal 'Merge the quarterly datasets on row index' should not be used.
Incorrect Answers
A:This addresses a different case: An old application exports OrderFlag values Y and N, while a new semantic model needs true Boolean values. It is not the specific defect in 'Merge the quarterly datasets on row index'.
C:Product familiarity is not evidence of suitability. The actual defect in this proposal is: Joining by position can corrupt transactions and does not combine sequential periods.
D:This is reasoning supporting the preferred solution 'Append the quarterly queries into one transaction table', but it does not directly name the defect in the proposed shortcut.
Question 143
Quarterly sales CSV files have the same column layout and should form one continuous fact table. After implementing Append the quarterly queries into one transaction table, which observation BEST demonstrates that the intended result is actually working?
- The resulting fact contains records from all four quarters with no dropped periods
- The team schedules a future check of whether The resulting fact contains records from all four quarters with no dropped periods, but has not observed a result.
- The report owner approves Append the quarterly queries into one transaction table without testing the resulting behavior.
- All Y records become true and N records false after refresh
Explanation
Correct Answer
A:The observation 'The resulting fact contains records from all four quarters with no dropped periods' directly tests the intended result. Append stacks compatible row sets rather than joining them horizontally.
Incorrect Answers
B:A future test is not yet observed operational evidence. The verification must establish: The resulting fact contains records from all four quarters with no dropped periods.
C:Approval of a proposed design is not evidence of working behavior. The required observation is: The resulting fact contains records from all four quarters with no dropped periods.
D:This belongs to a different case: An old application exports OrderFlag values Y and N, while a new semantic model needs true Boolean values. It does not validate the current change.
Question 144
The original scenario was: Quarterly sales CSV files have the same column layout and should form one continuous fact table. The initial solution is already in place. Now this new requirement arises: The next quarter introduces a new optional column. Which ADDITIONAL action BEST meets the changed condition?
- The resulting fact contains records from all four quarters with no dropped periods
- Align the schemas explicitly before appending the changed file
- Merge the quarterly datasets on row index
- Append the quarterly queries into one transaction table
Explanation
Correct Answer
B:The changed requirement is 'The next quarter introduces a new optional column'. The additional response is 'Align the schemas explicitly before appending the changed file'.
Incorrect Answers
A:This observes the original approach but is not an additional action: The resulting fact contains records from all four quarters with no dropped periods.
C:This remains unsuitable for the original situation: Joining by position can corrupt transactions and does not combine sequential periods. It also does not meet the changed need.
D:This is the already implemented original solution: Append the quarterly queries into one transaction table. Append stacks compatible row sets rather than joining them horizontally. It does not itself solve the new requirement.
Question 145
An order fact has ProductID and must display ProductCategory from a product reference table. Which approach BEST meets the stated Microsoft Power BI requirement?
- Append Products rows below the Orders fact
- Join using an effective-dated surrogate product key
- Merge with Products on ProductID using a correctly typed join key
- Use Group By CustomerID with Sum over the sales amount
Explanation
Correct Answer
C:Merge joins related columns using matching keys. For the stated case, Merge with Products on ProductID using a correctly typed join key.
Incorrect Answers
A:Appending different entity types cannot enrich a fact with product attributes. The proposed shortcut 'Append Products rows below the Orders fact' fails the documented need.
B:This might be appropriate after a different requirement arises: Products may have several historical category versions. It is not the best initial response to the stated case.
D:This addresses a separate source situation: A sales table has many order lines per customer, and the team wants total revenue by CustomerID. It does not directly satisfy this case's priority.
Question 146
An order fact has ProductID and must display ProductCategory from a product reference table. A colleague proposes: Append Products rows below the Orders fact. Which explanation BEST identifies the defect in that proposal?
- Deduplication discards valid transactions instead of summing them
- Merge joins related columns using matching keys
- Appending different entity types cannot enrich a fact with product attributes
- The suggested approach is safe merely because its product name is familiar.
Explanation
Correct Answer
C:Appending different entity types cannot enrich a fact with product attributes. This directly explains why the proposal 'Append Products rows below the Orders fact' should not be used.
Incorrect Answers
A:This addresses a different case: A sales table has many order lines per customer, and the team wants total revenue by CustomerID. It is not the specific defect in 'Append Products rows below the Orders fact'.
B:This is reasoning supporting the preferred solution 'Merge with Products on ProductID using a correctly typed join key', but it does not directly name the defect in the proposed shortcut.
D:Product familiarity is not evidence of suitability. The actual defect in this proposal is: Appending different entity types cannot enrich a fact with product attributes.
Question 147
An order fact has ProductID and must display ProductCategory from a product reference table. After implementing Merge with Products on ProductID using a correctly typed join key, which observation BEST demonstrates that the intended result is actually working?
- The enriched order rows show the expected product category for matching keys
- The report owner approves Merge with Products on ProductID using a correctly typed join key without testing the resulting behavior.
- The team schedules a future check of whether The enriched order rows show the expected product category for matching keys, but has not observed a result.
- The grouped table's customer totals match independently calculated source sums
Explanation
Correct Answer
A:The observation 'The enriched order rows show the expected product category for matching keys' directly tests the intended result. Merge joins related columns using matching keys.
Incorrect Answers
B:Approval of a proposed design is not evidence of working behavior. The required observation is: The enriched order rows show the expected product category for matching keys.
C:A future test is not yet observed operational evidence. The verification must establish: The enriched order rows show the expected product category for matching keys.
D:This belongs to a different case: A sales table has many order lines per customer, and the team wants total revenue by CustomerID. It does not validate the current change.
Question 148
The original scenario was: An order fact has ProductID and must display ProductCategory from a product reference table. The initial solution is already in place. Now this new requirement arises: Products may have several historical category versions. Which ADDITIONAL action BEST meets the changed condition?
- Merge with Products on ProductID using a correctly typed join key
- Join using an effective-dated surrogate product key
- Append Products rows below the Orders fact
- The enriched order rows show the expected product category for matching keys
Explanation
Correct Answer
B:The changed requirement is 'Products may have several historical category versions'. The additional response is 'Join using an effective-dated surrogate product key'.
Incorrect Answers
A:This is the already implemented original solution: Merge with Products on ProductID using a correctly typed join key. Merge joins related columns using matching keys. It does not itself solve the new requirement.
C:This remains unsuitable for the original situation: Appending different entity types cannot enrich a fact with product attributes. It also does not meet the changed need.
D:This observes the original approach but is not an additional action: The enriched order rows show the expected product category for matching keys.
Question 149
An analyst must retain every sale even when a matching product master row is missing. Which approach BEST meets the stated Microsoft Power BI requirement?
- Apply an explicitly approved Inner join to the export-specific query
- Use an Inner join and assume unmatched sales are kept
- Use Append Queries instead of Merge Queries
- Use a Left Outer merge from Sales to Products
Explanation
Correct Answer
D:A left outer join preserves all rows from the left fact query. For the stated case, Use a Left Outer merge from Sales to Products.
Incorrect Answers
A:This might be appropriate after a different requirement arises: Business rules later require discarding unrecognized products for an export. It is not the best initial response to the stated case.
B:Inner joins remove fact rows lacking a matching dimension key. The proposed shortcut 'Use an Inner join and assume unmatched sales are kept' fails the documented need.
C:This addresses a separate source situation: An analyst combines two tables that have the same columns but distinct store-region rows. It does not directly satisfy this case's priority.
Question 150
An analyst must retain every sale even when a matching product master row is missing. A colleague proposes: Use an Inner join and assume unmatched sales are kept. Which explanation BEST identifies the defect in that proposal?
- A join may duplicate or drop rows instead of adding region transactions
- A left outer join preserves all rows from the left fact query
- The suggested approach is safe merely because its product name is familiar.
- Inner joins remove fact rows lacking a matching dimension key
Explanation
Correct Answer
D:Inner joins remove fact rows lacking a matching dimension key. This directly explains why the proposal 'Use an Inner join and assume unmatched sales are kept' should not be used.
Incorrect Answers
A:This addresses a different case: An analyst combines two tables that have the same columns but distinct store-region rows. It is not the specific defect in 'Use an Inner join and assume unmatched sales are kept'.
B:This is reasoning supporting the preferred solution 'Use a Left Outer merge from Sales to Products', but it does not directly name the defect in the proposed shortcut.
C:Product familiarity is not evidence of suitability. The actual defect in this proposal is: Inner joins remove fact rows lacking a matching dimension key.