Microsoft DP-900 Practice Test 79
Question 780
A stock clerk needs to add an item adjust its price and retire a discontinued row. After selecting the proper INSERT UPDATE DELETE DML approach, which observation gives the clearest evidence of success?
- The intended rows change while unrelated records remain intact.
- Customers without orders remain visible with null child values.
- Authorized identities connect within assigned privileges and revoked users fail.
- Allowed read-only workloads use designated replicas without violating freshness needs.
Explanation
Correct Answer
A:The intended rows change while unrelated records remain intact. This is the directly observable result for INSERT UPDATE DELETE DML; data manipulation language changes rows rather than defining the schema.
Incorrect Answers
B:Customers without orders remain visible with null child values. This supports Left outer join preserving parents, not confirmation of INSERT UPDATE DELETE DML. The relevant evidence is that the intended rows change while unrelated records remain intact.
C:Authorized identities connect within assigned privileges and revoked users fail. This supports Azure SQL authentication and Entra identity, not confirmation of INSERT UPDATE DELETE DML. The relevant evidence is that the intended rows change while unrelated records remain intact.
D:Allowed read-only workloads use designated replicas without violating freshness needs. This supports Azure SQL read scale and reporting replicas, not confirmation of INSERT UPDATE DELETE DML. The relevant evidence is that the intended rows change while unrelated records remain intact.
Question 781
Every query scans all historical files even for a narrow date filter. During testing, the team observes this specific failure: Overpartitioning by a unique row ID creates tiny files and overhead. Which corrective check should be performed FIRST?
- Name a folder January and assume every query optimizer recognizes it without partition metadata.
- Compare bytes read for one-month queries before and after layout.
- Use Azure Stream Analytics job inputs queries and compatible outputs.
- Use complementary file-based lake storage and relational analytics tables as needed.
Explanation
Correct Answer
B:Compare bytes read for one-month queries before and after layout. A successful correction should demonstrate that the engine scans relevant partitions rather than every archive folder.
Incorrect Answers
A:Name a folder January and assume every query optimizer recognizes it without partition metadata. This reinforces the error rather than addressing the Data lake partition pruning failure. Partition pruning reduces I/O when filters align with physical layout.
C:Use Azure Stream Analytics job inputs queries and compatible outputs. It serves Azure Stream Analytics SQL-like streaming, not the diagnosed Data lake partition pruning problem. Overpartitioning by a unique row ID creates tiny files and overhead.
D:Use complementary file-based lake storage and relational analytics tables as needed. It serves Structured warehouse and unstructured lake coexistence, not the diagnosed Data lake partition pruning problem. Overpartitioning by a unique row ID creates tiny files and overhead.
Question 782
A team wants historical sales slicing without locking the operational checkout database. Which principle BEST explains the correct OLTP relational versus OLAP analytical store design decision?
- JSON arrays hold ordered elements whereas objects group named properties.
- File storage and searchable record databases serve different access patterns.
- Timestamp interpretation needs explicit timezone conventions for cross-region analysis.
- OLTP emphasizes short consistent transactions whereas OLAP emphasizes aggregated analytical reads.
Explanation
Correct Answer
D:OLTP emphasizes short consistent transactions whereas OLAP emphasizes aggregated analytical reads. In this case the applicable decision is to separate transaction-optimized writes from analytical aggregation workloads as needed.
Incorrect Answers
A:JSON arrays hold ordered elements whereas objects group named properties. That concept explains JSON arrays and nested objects; the situation instead concerns OLTP relational versus OLAP analytical store. Running massive unbounded analytics queries on a critical transactional database may hurt performance.
B:File storage and searchable record databases serve different access patterns. That concept explains File store versus database selection; the situation instead concerns OLTP relational versus OLAP analytical store. Running massive unbounded analytics queries on a critical transactional database may hurt performance.
C:Timestamp interpretation needs explicit timezone conventions for cross-region analysis. That concept explains Timestamp and timezone representation; the situation instead concerns OLTP relational versus OLAP analytical store. Running massive unbounded analytics queries on a critical transactional database may hurt performance.
Question 783
An application stores product photographs as named objects in a media container. Which choice BEST meets this requirement?
- Enable suitable blob soft delete retention and test restore.
- Configure supported Cosmos DB geographic replication and eligible failover strategy.
- Rename a Blob container to a SQL database and assume JOIN works.
- Place suitable data objects in Blob Storage containers with governed object names.
Explanation
Correct Answer
D:Blob Storage provides object-based access with containers and blobs.
Incorrect Answers
A:Enable suitable blob soft delete retention and test restore. That action primarily handles Blob soft delete recovery; the given requirement is Blob storage object and container hierarchy. Blob Storage provides object-based access with containers and blobs.
B:Configure supported Cosmos DB geographic replication and eligible failover strategy. That action primarily handles Cosmos DB multi-region distribution; the given requirement is Blob storage object and container hierarchy. Blob Storage provides object-based access with containers and blobs.
C:Rename a Blob container to a SQL database and assume JOIN works. It does not implement Blob storage object and container hierarchy. Treating container names as database tables with SQL joins causes unsupported queries.
Question 784
Management wants sales by month then by individual store. After selecting the proper Data analyst slicing and drill-down approach, which observation gives the clearest evidence of success?
- Users move from aggregate to detail with correct filter behavior.
- Valid documents lacking optional properties remain queryable without false errors.
- Queries read relevant columns efficiently while preserving typed values.
- Threshold breaches trigger timely investigation before service outage.
Explanation
Correct Answer
A:Users move from aggregate to detail with correct filter behavior. This is the directly observable result for Data analyst slicing and drill-down; drill-down and slicing reveal patterns across levels of analysis.
Incorrect Answers
B:Valid documents lacking optional properties remain queryable without false errors. This supports Sparse document attributes, not confirmation of Data analyst slicing and drill-down. The relevant evidence is that users move from aggregate to detail with correct filter behavior.
C:Queries read relevant columns efficiently while preserving typed values. This supports Parquet columnar analytical file, not confirmation of Data analyst slicing and drill-down. The relevant evidence is that users move from aggregate to detail with correct filter behavior.
D:Threshold breaches trigger timely investigation before service outage. This supports DBA monitoring capacity and alerts, not confirmation of Data analyst slicing and drill-down. The relevant evidence is that users move from aggregate to detail with correct filter behavior.
Question 785
Data ingest jobs fail when CSV column types drift. What is the MOST appropriate next validation or correction?
- Test SQL queries transaction rollback and service configuration.
- Simulate delayed upstream processing and inspect downstream execution order.
- Replay old and new sample payloads through tests.
- Ignore schema changes because data arrived over HTTPS.
Explanation
Correct Answer
C:Replay old and new sample payloads through tests. This tests the intended result: unexpected schema changes are quarantined or mapped deliberately.
Incorrect Answers
A:Test SQL queries transaction rollback and service configuration. It tests Azure SQL Database managed relational app rather than the critical Data engineer schema and format changes behavior. Data engineers maintain resilient transformations when source structures change.
B:Simulate delayed upstream processing and inspect downstream execution order. It tests Data engineer orchestration dependencies rather than the critical Data engineer schema and format changes behavior. Data engineers maintain resilient transformations when source structures change.
D:Ignore schema changes because data arrived over HTTPS. This unsafe shortcut leaves the Data engineer schema and format changes problem unresolved. Silently dropping changed fields can produce inaccurate downstream analytics.
Question 786
Web session logs should group clicks separated by less than thirty minutes. After selecting the proper Session windows of event activity approach, which observation gives the clearest evidence of success?
- Fraud alerts arrive promptly while daily reports complete within their SLA.
- Separate bursts form distinct sessions after gaps exceed policy.
- Distributed transformations produce correct partitions and aggregated outputs.
- Separate reports calculate the same KPI under equivalent filters.
Explanation
Correct Answer
B:Separate bursts form distinct sessions after gaps exceed policy. This is the directly observable result for Session windows of event activity; session windows depend on activity gaps rather than rigid wall-clock buckets.
Incorrect Answers
A:Fraud alerts arrive promptly while daily reports complete within their SLA. This supports Streaming versus batch latency choice, not confirmation of Session windows of event activity. The relevant evidence is that separate bursts form distinct sessions after gaps exceed policy.
C:Distributed transformations produce correct partitions and aggregated outputs. This supports Azure Databricks Apache Spark processing, not confirmation of Session windows of event activity. The relevant evidence is that separate bursts form distinct sessions after gaps exceed policy.
D:Separate reports calculate the same KPI under equivalent filters. This supports Semantic model over curated analytics, not confirmation of Session windows of event activity. The relevant evidence is that separate bursts form distinct sessions after gaps exceed policy.
Question 787
An analyst can accidentally drop production tables. Which choice BEST meets this requirement?
- Hide the DROP button in a UI and assume database permissions disappear.
- Fit an appropriately validated forecasting or classification model on relevant data.
- Restrict database roles and grants to job-specific permissions.
- Validate data quality and compare segmented trends before conclusions.
Explanation
Correct Answer
C:Restrict database roles and grants to job-specific permissions. Database access governance is an administrative responsibility. In the stated case, verification should show that tests confirm analysts can SELECT approved data but cannot DROP tables.
Incorrect Answers
A:Hide the DROP button in a UI and assume database permissions disappear. It does not implement DBA least privilege account roles. Giving every reader db_owner increases accidental and malicious impact.
B:Fit an appropriately validated forecasting or classification model on relevant data. That action primarily handles Predictive analytics forecasts; the given requirement is DBA least privilege account roles. Database access governance is an administrative responsibility.
D:Validate data quality and compare segmented trends before conclusions. That action primarily handles Data analyst anomaly interpretation; the given requirement is DBA least privilege account roles. Database access governance is an administrative responsibility.
Question 788
A customer table must distinguish two people with the same display name. After selecting the proper Primary key row uniqueness approach, which observation gives the clearest evidence of success?
- Only groups whose computed total crosses the threshold remain.
- Compute usage matches active demand and wake-up behavior meets latency targets.
- Duplicate primary-key inserts are rejected and lookups find one intended row.
- Database service updates are managed while customer-owned logic is tested.
Explanation
Correct Answer
C:Duplicate primary-key inserts are rejected and lookups find one intended row. This is the directly observable result for Primary key row uniqueness; a primary key enforces row identity while nonkey fields may repeat.
Incorrect Answers
A:Only groups whose computed total crosses the threshold remain. This supports SQL HAVING after grouping, not confirmation of Primary key row uniqueness. The relevant evidence is that duplicate primary-key inserts are rejected and lookups find one intended row.
B:Compute usage matches active demand and wake-up behavior meets latency targets. This supports Azure SQL Database serverless compute, not confirmation of Primary key row uniqueness. The relevant evidence is that duplicate primary-key inserts are rejected and lookups find one intended row.
D:Database service updates are managed while customer-owned logic is tested. This supports Azure SQL managed maintenance responsibility, not confirmation of Primary key row uniqueness. The relevant evidence is that duplicate primary-key inserts are rejected and lookups find one intended row.
Question 789
A warehouse needs to reflect inserts and updates from an operational database. If the relevant CDC propagation to analytics safeguard is skipped, which failure is MOST directly associated with that omission?
- Advancing the watermark before successful commit may skip data.
- Ignoring deletes or duplicate delivery can create stale or extra facts.
- Confusing stream discovery with a durable historical table leaves retention unspecified.
- Assuming order across unrelated partitions can corrupt sequence reconstruction.
Explanation
Correct Answer
B:Ignoring deletes or duplicate delivery can create stale or extra facts. CDC propagates database changes without resnapshotting every row. A suitable check is to test create update delete sequence and restart checkpoint behavior.
Incorrect Answers
A:Advancing the watermark before successful commit may skip data. This failure is associated with Incremental ingestion with watermark; it is not the primary failure in the stated CDC propagation to analytics scenario. CDC propagates database changes without resnapshotting every row.
C:Confusing stream discovery with a durable historical table leaves retention unspecified. This failure is associated with Fabric Real-Time hub stream discovery; it is not the primary failure in the stated CDC propagation to analytics scenario. CDC propagates database changes without resnapshotting every row.
D:Assuming order across unrelated partitions can corrupt sequence reconstruction. This failure is associated with Event streams partitioning and key order; it is not the primary failure in the stated CDC propagation to analytics scenario. CDC propagates database changes without resnapshotting every row.
Question 790
Multiple reports need identical monthly revenue definitions. After selecting the proper Semantic model over curated analytics approach, which observation gives the clearest evidence of success?
- Separate reports calculate the same KPI under equivalent filters.
- A single event can contribute to overlapping eligible windows.
- Refresh applies the same cleanup to new records.
- The chosen experience supports required processing and consumption without undue copying.
Explanation
Correct Answer
A:Separate reports calculate the same KPI under equivalent filters. This is the directly observable result for Semantic model over curated analytics; semantic modeling makes reusable business meanings above source tables.
Incorrect Answers
B:A single event can contribute to overlapping eligible windows. This supports Hopping sliding analytic windows, not confirmation of Semantic model over curated analytics. The relevant evidence is that separate reports calculate the same KPI under equivalent filters.
C:Refresh applies the same cleanup to new records. This supports Power Query shaping transformation, not confirmation of Semantic model over curated analytics. The relevant evidence is that separate reports calculate the same KPI under equivalent filters.
D:The chosen experience supports required processing and consumption without undue copying. This supports Lakehouse versus Warehouse selection, not confirmation of Semantic model over curated analytics. The relevant evidence is that separate reports calculate the same KPI under equivalent filters.