Microsoft Power BI Data Analyst PL-300 Practice Test 4
Question 30
A trading dashboard must query a supported warehouse's latest committed orders when analysts filter the page and must avoid retaining transaction rows in the model. Which Power BI or Power Query action BEST meets the stated requirement?
- Select a DirectQuery connection to the supported warehouse
- Copy monthly CSV extracts into a static lookup table
- Import the warehouse fact table once a week
- Configure a scheduled Import refresh and treat its cached rows as live
Explanation
Correct Answer
A:DirectQuery sends queries to the source during interactions rather than maintaining a full imported fact cache This addresses the specific requirement: a trading dashboard must query a supported warehouse's latest committed orders when analysts filter the page and must avoid retaining transaction rows in the model.
Incorrect Answers
B:A static extract cannot query newly committed source transactions interactively This alternative therefore fails an explicit scenario constraint.
C:Weekly import cannot satisfy up-to-date filtered order results This alternative therefore fails an explicit scenario constraint.
D:A refresh schedule leaves latency between source changes and imported data This alternative therefore fails an explicit scenario constraint.
Question 31
An API returns a list of JSON objects with nested contact records and the model needs CustomerID and nested City in ordinary columns. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- The query finishes refresh without errors, but resulting totals and keys have not been reconciled
- Each customer row exposes CustomerID and the correctly expanded City field
- A single example row looks plausible, but unmatched keys and duplicate matches were not examined
- The transformed table displays expected column headings, but the underlying row grain has not been checked
Explanation
Correct Answer
B:Each customer row exposes CustomerID and the correctly expanded City field This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
A:A successful refresh can still yield the wrong business grain or aggregate values.
C:One positive example can conceal lost or multiplied rows elsewhere in the reshaped data.
D:Correct headers alone do not demonstrate correct append, merge, pivot or group-by cardinality.
Question 32
A column profiling display reports 15 percent error cells and 9 percent empty cells, but the editor preview contains only the first thousand records. Which Power BI or Power Query action BEST meets the stated requirement?
- Use only the first displayed 1,000 rows as the quality baseline
- Turn off profiling and infer column types from the header text
- Treat all blank cells as Power Query errors
- Switch profiling to the entire dataset before making data-quality decisions
Explanation
Correct Answer
D:Full-dataset profiling avoids assuming a sample accurately represents the complete population This addresses the specific requirement: a column profiling display reports 15 percent error cells and 9 percent empty cells, but the editor preview contains only the first thousand records.
Incorrect Answers
A:A sample can hide errors and null distributions outside its preview window This alternative therefore fails an explicit scenario constraint.
B:Headers do not measure value quality or reveal parsing errors This alternative therefore fails an explicit scenario constraint.
C:Blank and error values are distinct states in column quality statistics This alternative therefore fails an explicit scenario constraint.
Question 33
A company has a certified enterprise sales semantic model and wants a new report without creating another independent copy of its tables. A pilot instead implemented the following proposed change: Import a new copy of the transaction CSV into a separate model. The business requirement was not met. Which technical limitation MOST DIRECTLY explains the result?
- Calculated tables duplicate model logic rather than consuming the published semantic model
- A separate imported model can diverge from certified measures and permissions
- Copied visual layout alone does not connect to the certified underlying model
- A live connection reuses the governed model measures and business definitions rather than importing another copy
Explanation
Correct Answer
B:A separate imported model can diverge from certified measures and permissions This specifically addresses the deployed or proposed alternative: Import a new copy of the transaction CSV into a separate model.
Incorrect Answers
A:Calculated tables duplicate model logic rather than consuming the published semantic model That limitation describes Create calculated tables to reproduce every shared measure, not the specified approach.
C:Copied visual layout alone does not connect to the certified underlying model That limitation applies to a different alternative (Copy the existing report pages into a new disconnected PBIX), not the one here.
D:A live connection reuses the governed model measures and business definitions rather than importing another copy This supports the recommended design but does not diagnose why the specified alternative fails.
Question 34
An imported spreadsheet has weeks in rows and store IDs as header columns, but the requested result is one row per store-week with a single Sales column. Which Power BI or Power Query action BEST meets the stated requirement?
- Remove the Week field to simplify the query
- Merge the table with itself on Store
- Pivot Week and retain store headers
- Unpivot the store ID columns while preserving Week
Explanation
Correct Answer
D:Unpivot converts multiple store headers into Store and Sales rows with a week identifier This addresses the specific requirement: an imported spreadsheet has weeks in rows and store IDs as header columns, but the requested result is one row per store-week with a single Sales column.
Incorrect Answers
A:Without Week the required store-week identity is lost This alternative therefore fails an explicit scenario constraint.
B:A self-merge cannot reshape the repeated store columns into tidy row values This alternative therefore fails an explicit scenario constraint.
C:Pivot makes additional columns rather than the desired long grain This alternative therefore fails an explicit scenario constraint.
Question 35
A published Import model loads from a corporate SQL database but works in Desktop only; the scheduled service refresh reports invalid credentials. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- The service connection test succeeds and the next scheduled refresh completes using the authorized credentials
- Power BI Desktop shows a successful source preview, but no service connection or target refresh has been exercised
- One report visual renders without an error while its data recency and intended source identity remain unchecked
- The connection settings have been saved, but no comparison to the required source data has been made
Explanation
Correct Answer
A:The service connection test succeeds and the next scheduled refresh completes using the authorized credentials This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
B:A Desktop preview establishes local connectivity only; it does not verify the published data-access behavior requested here.
C:An error-free visual might be cached or backed by the wrong source; it does not test the specified freshness or connectivity boundary.
D:Saved configuration is not evidence that the selected storage/credential behavior returns the intended records.
Question 36
A base Power Query applies cleaning rules used by three downstream data marts and all should inherit subsequent base-query changes. A design reviewer proposes this alternative: Copy the resulting table into a static worksheet. Which objection BEST explains why it would not satisfy the stated requirement?
- DAX tables do not automatically reuse the maintained Power Query cleaning pipeline
- Reference depends on upstream query steps and reflects their later changes
- Duplicate makes independent copies of steps and later edits to the base do not propagate
- Static copies do not inherit subsequent query transformation updates
Explanation
Correct Answer
D:Static copies do not inherit subsequent query transformation updates This specifically addresses the deployed or proposed alternative: Copy the resulting table into a static worksheet.
Incorrect Answers
A:DAX tables do not automatically reuse the maintained Power Query cleaning pipeline That limitation describes Build separate calculated DAX tables from raw files, not the specified approach.
B:Reference depends on upstream query steps and reflects their later changes This supports the recommended design but does not diagnose why the specified alternative fails.
C:Duplicate makes independent copies of steps and later edits to the base do not propagate That limitation applies to a different alternative (Create unrelated Duplicate queries for each mart), not the one here.
Question 37
A column profiling display reports 15 percent error cells and 9 percent empty cells, but the editor preview contains only the first thousand records. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- The query loads successfully, but distinct values and data-quality exceptions were not checked
- Column quality and distribution statistics recompute over the full dataset and reveal off-preview issues
- The first thousand preview rows look correct, but the known invalid or missing records have not been examined
- The column type icon appears correct, but a source-to-result reconciliation has not been performed
Explanation
Correct Answer
B:Column quality and distribution statistics recompute over the full dataset and reveal off-preview issues This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
A:Successful load does not prove the requested missing-value or identity semantics were preserved.
C:A short preview may miss the very error, locale or null condition that the cleaning rule must handle.
D:The declared type alone cannot establish that actual identifiers, dates or values survived transformation.
Question 38
A DirectQuery report requires each user's region slicer to restrict the rows scanned by a supported source query rather than retrieving all regions first. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- The connection settings have been saved, but no comparison to the required source data has been made
- Changing the region selection changes the generated source query parameter in a supported DirectQuery model
- Power BI Desktop shows a successful source preview, but no service connection or target refresh has been exercised
- One report visual renders without an error while its data recency and intended source identity remain unchecked
Explanation
Correct Answer
B:Changing the region selection changes the generated source query parameter in a supported DirectQuery model This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
A:Saved configuration is not evidence that the selected storage/credential behavior returns the intended records.
C:A Desktop preview establishes local connectivity only; it does not verify the published data-access behavior requested here.
D:An error-free visual might be cached or backed by the wrong source; it does not test the specified freshness or connectivity boundary.
Question 39
A transaction feed exposes reusable customer IDs but contains duplicate names and the business needs consistent relationships across order and support facts. After the correct solution is implemented, which result provides the MOST DIRECT evidence that the requirement actually works?
- A test customer key maps to one dimension row and filters both fact tables consistently
- The transformed table displays expected column headings, but the underlying row grain has not been checked
- The query finishes refresh without errors, but resulting totals and keys have not been reconciled
- A single example row looks plausible, but unmatched keys and duplicate matches were not examined
Explanation
Correct Answer
A:A test customer key maps to one dimension row and filters both fact tables consistently This exercises the requested business outcome and the necessary positive or negative boundary.
Incorrect Answers
B:Correct headers alone do not demonstrate correct append, merge, pivot or group-by cardinality.
C:A successful refresh can still yield the wrong business grain or aggregate values.
D:One positive example can conceal lost or multiplied rows elsewhere in the reshaped data.
Question 40
An API returns a list of JSON objects with nested contact records and the model needs CustomerID and nested City in ordinary columns. A pilot instead implemented the following proposed change: Treat the entire JSON payload as a single text value. The business requirement was not met. Which technical limitation MOST DIRECTLY explains the result?
- Text storage leaves nested City inaccessible as a modeled column
- Transposition does not parse nested object properties
- Expanding record fields exposes nested properties as query columns
- Payload length is unrelated to the required nested attribute
Explanation
Correct Answer
A:Text storage leaves nested City inaccessible as a modeled column This specifically addresses the deployed or proposed alternative: Treat the entire JSON payload as a single text value.
Incorrect Answers
B:Transposition does not parse nested object properties That limitation applies to a different alternative (Transpose the JSON document before parsing its structure), not the one here.
C:Expanding record fields exposes nested properties as query columns This supports the recommended design but does not diagnose why the specified alternative fails.
D:Payload length is unrelated to the required nested attribute That limitation describes Group the raw JSON by record length, not the specified approach.