DP-900 Describe core data concepts Practice Test 3 — 15 Questions

Question 1

A retail company stores product information in a relational database table with fixed columns: ProductID (integer), Name (string), Price (decimal). They also store customer reviews as JSON documents where each review may contain different fields such as rating, comment, and optional images. Additionally, they store product images as JPEG files in Azure Blob Storage. Which of the following correctly classifies these data types from most structured to least structured?

Accepted Answer

Structured (product info), Semi-structured (reviews), Unstructured (images). Product info in a relational table with fixed columns (ProductID, Name, Price) is structured data. Customer reviews stored as JSON documents, which may have varying fields like rating, comment, and optional images, are semi-structured because they have a flexible schema. Product images stored as JPEG files in Azure Blob Storage are unstructured binary data. This ordering from most to least structured matches option A.

Answer

Semi-structured (product info), Structured (reviews), Unstructured (images)

Answer

Unstructured (product info), Semi-structured (reviews), Structured (images)

Answer

Structured (product info), Unstructured (reviews), Semi-structured (images)

Question 2

A logistics company ingests GPS coordinates from delivery trucks in real-time to update a live tracking dashboard. They also run a nightly job to aggregate the day's deliveries into a report stored in Azure SQL Database. Which statement correctly describes the data processing types used for these two workloads?

Accepted Answer

GPS ingestion is stream processing; nightly aggregation is batch processing.. Option A is correct because the real-time ingestion of GPS coordinates from delivery trucks is a classic stream processing workload, where data is processed continuously as it arrives with low latency. The nightly aggregation of daily deliveries into a report stored in Azure SQL Database is a batch processing workload, where data is processed in bulk at scheduled intervals. Azure Stream Analytics is commonly used for the streaming ingestion, while Azure SQL Database or Azure Synapse Analytics can handle the batch aggregation.

Answer

GPS ingestion is batch processing; nightly aggregation is stream processing.

Answer

Both workloads are examples of stream processing.

Answer

Both workloads are examples of batch processing.

Question 3

A company stores customer data in a relational table with columns CustomerID, FullName, and Email. They also store product descriptions as JSON documents with varying fields, and product images as JPEG files. Which of the following correctly classifies these data types from most structured to least structured?

Accepted Answer

Structured, semi-structured, unstructured. The customer data in a relational table with fixed columns (CustomerID, FullName, Email) is structured because it has a rigid schema and defined data types. The JSON documents for product descriptions are semi-structured because they use key-value pairs with flexible fields but still have metadata (tags, keys) that provide organization. The JPEG product images are unstructured because they are binary blobs with no inherent schema or metadata that the database can query directly. This ordering from most to least structured matches option A.

Answer

Unstructured, semi-structured, structured

Answer

Semi-structured, structured, unstructured

Answer

Structured, unstructured, semi-structured

Question 4

A financial services company stores account balances in Azure SQL Database (strong consistency) and transaction audit logs in Azure Cosmos DB (eventual consistency by default). A compliance requirement demands that when a transaction is rolled back in the SQL database, the corresponding audit log entries in Cosmos DB must also be removed within a short time frame. Which term best describes the difficulty of maintaining this constraint?

Accepted Answer

Distributed transaction coordination. Option C is correct because the scenario requires coordinating a rollback across two distinct data stores—Azure SQL Database (ACID-compliant, strong consistency) and Azure Cosmos DB (eventual consistency by default). This cross-system transactional consistency is a classic distributed transaction coordination problem, often addressed via patterns like the two-phase commit (2PC) or the saga pattern, but not natively supported between these two services without custom orchestration.

Answer

ACID compliance

Answer

Idempotency

Answer

Schema flexibility

Question 5

A company stores customer data in a relational table with fixed columns: CustomerID (integer), FirstName (string), LastName (string), Email (string). They also store product images as JPEG files in Azure Blob Storage, and customer feedback as JSON documents where each document may contain fields such as rating, comment, and optional metadata. Which of the following correctly classifies these data types?

Accepted Answer

Relational table – structured, JPEG – unstructured, JSON – semi-structured. Option A is correct because a relational table with fixed columns and data types (CustomerID, FirstName, LastName, Email) stores structured data with a rigid schema. JPEG files in Azure Blob Storage are binary blobs with no internal structure that a database can interpret, making them unstructured. JSON documents with optional fields (like rating, comment, metadata) have a flexible schema that can vary per document, which is the definition of semi-structured data.

Answer

Relational table – structured, JPEG – semi-structured, JSON – unstructured

Answer

Relational table – semi-structured, JPEG – unstructured, JSON – structured

Answer

Relational table – unstructured, JPEG – structured, JSON – semi-structured

Question 6

A financial services company is evaluating distributed NoSQL databases for a new application that must remain fully available even during network partitions. The application can tolerate stale reads for some types of queries. Which statement accurately describes the trade-off described by the CAP theorem in this context?

Accepted Answer

When a network partition occurs, a distributed system must choose between providing consistency and providing availability.. The CAP theorem states that during a network partition (P), a distributed system must choose between consistency (C) and availability (A). Since the application requires full availability even during partitions, it must sacrifice strong consistency in favor of eventual consistency, which tolerates stale reads. Option B correctly captures this fundamental trade-off.

Answer

During a network partition, the system can maintain both consistency and availability.

Answer

Partition tolerance is an optional property and can be sacrificed to achieve both consistency and availability.

Answer

Availability guarantees that every read returns the most recent write.

Question 7

A retail company operates an online store. The store processes each customer's order immediately upon submission, updating inventory and payment records in real-time. Additionally, the company's business analysts run weekly reports that aggregate sales data over the past month to identify trends. Which of the following correctly describes the two workload types represented in this scenario?

Accepted Answer

The order processing is an OLTP workload; the weekly reporting is an OLAP workload.. The order processing system handles individual transactions (inserts/updates) in real-time, which is the hallmark of an Online Transaction Processing (OLTP) workload. The weekly reporting aggregates large volumes of historical data for trend analysis, which is an Online Analytical Processing (OLAP) workload. OLTP is optimized for high-volume, low-latency writes, while OLAP is optimized for complex read-heavy queries over large datasets.

Answer

The order processing is an OLAP workload; the weekly reporting is an OLTP workload.

Answer

Both workloads are OLTP workloads.

Answer

Both workloads are batch processing workloads.

Question 8

A company stores customer data in a relational table with fixed columns: CustomerID (integer), FirstName (string), LastName (string), Email (string). They also store product images as JPEG files, and customer feedback as JSON documents that may contain varying fields such as rating, comment, and optional metadata. Which of the following correctly orders these data types from most structured to least structured?

Accepted Answer

Relational table, JSON documents, JPEG files. The relational table is the most structured because it enforces a fixed schema with predefined columns and data types (e.g., CustomerID integer, FirstName string). JSON documents are semi-structured: they have a flexible schema where fields like rating and comment can vary per document, but they still provide key-value organization. JPEG files are unstructured binary data with no internal schema or queryable structure, making them the least structured.

Answer

JSON documents, relational table, JPEG files

Answer

JPEG files, JSON documents, relational table

Answer

Relational table, JPEG files, JSON documents

Question 9

A logistics company uses an online system to process incoming delivery requests one at a time, updating the database immediately upon each transaction. They also run a weekly job that analyzes thousands of delivery records to identify average delivery times and trends. Which set of terms correctly classifies these two workloads?

Accepted Answer

OLTP and OLAP. The first workload processes individual delivery requests with immediate database updates, which is the definition of Online Transaction Processing (OLTP). The second workload runs a weekly job analyzing thousands of records for trends and averages, which is Online Analytical Processing (OLAP). These two terms correctly classify the transactional and analytical workloads described.

Answer

Batch processing and real-time processing

Answer

Relational and non-relational

Answer

Structured and semi-structured

Question 10

A retail company processes historical sales data in a nightly batch job that loads aggregated reports into a data warehouse. Additionally, the company analyzes live customer interactions from their website to provide real-time product recommendations. Which pair of terms correctly describes these two data processing approaches?

Accepted Answer

Batch processing and streaming processing. The nightly batch job that loads aggregated reports into a data warehouse is a classic example of batch processing, where data is processed in large, scheduled chunks. The real-time analysis of live customer interactions for product recommendations is streaming processing, which handles data continuously as it arrives. Option B correctly pairs these two distinct processing paradigms.

Answer

OLTP and OLAP

Answer

Structured data and unstructured data

Answer

Relational and NoSQL

Question 11

A company stores customer names and addresses in a relational table, product descriptions as JSON files, and product images as JPEG files. Which of the following correctly classifies these data types from most structured to least structured?

Accepted Answer

Structured (customer table), Semi-structured (JSON), Unstructured (JPEG). A is correct because structured data (customer table) has a fixed schema with rows and columns, semi-structured data (JSON) uses tags or key-value pairs without a rigid schema, and unstructured data (JPEG) has no predefined structure. The question tests the standard classification hierarchy from most to least structured.

Answer

Structured (customer table), Unstructured (JSON), Semi-structured (JPEG)

Answer

Semi-structured (customer table), Structured (JSON), Unstructured (JPEG)

Answer

Unstructured (customer table), Structured (JSON), Semi-structured (JPEG)

Question 12

An e-commerce application processes customer orders. When an order is placed, the system must decrement the inventory count and process the payment. The application ensures that either both operations complete successfully or both are rolled back if any error occurs. Which database property does this guarantee?

Accepted Answer

Atomicity. Atomicity ensures that a transaction is treated as a single, indivisible unit of work: either all operations within it (decrement inventory and process payment) complete successfully, or none are applied. If any part fails, the database rolls back all changes, maintaining the 'all-or-nothing' guarantee. This is the core property described in the scenario.

Answer

Consistency

Answer

Isolation

Answer

Durability

Question 13

A retail company operates an online store. When a customer places an order, the system immediately updates inventory and payment records. Separately, the company's business analysts run weekly reports that aggregate sales data to identify trends. Which two terms correctly describe these workloads?

Accepted Answer

Batch processing and real-time processing. The order processing system that immediately updates inventory and payment records is a classic Online Transaction Processing (OLTP) workload, which handles high volumes of small, real-time transactions with ACID guarantees. The weekly sales aggregation reports run by business analysts are an Online Analytical Processing (OLAP) workload, which involves complex queries over large historical datasets to support business intelligence. Option B correctly pairs these two distinct processing paradigms.

Answer

Structured and Unstructured data

Answer

Data ingestion and data transformation

Question 14

A company is evaluating Azure database services for two different workloads. Workload A processes high-volume, low-latency transactions such as order entry and payment processing, where each transaction updates a few rows. Workload B involves running complex aggregations on terabytes of historical sales data to generate monthly business intelligence reports. Which Azure service is best suited for each workload?

Accepted Answer

B. Workload A: Azure Cosmos DB; Workload B: Azure Synapse Analytics. Workload A requires a low-latency, high-throughput transactional database capable of handling many small, row-level updates. Azure Cosmos DB is a NoSQL database designed for single-digit millisecond latency and horizontal scaling, making it ideal for order entry and payment processing. Workload B involves complex aggregations on terabytes of historical data, which is best handled by Azure Synapse Analytics, a distributed analytics service that uses massively parallel processing (MPP) to run large-scale queries efficiently.

Answer

A. Workload A: Azure SQL Database; Workload B: Azure Cosmos DB

Answer

C. Workload A: Azure Synapse Analytics; Workload B: Azure SQL Database

Answer

D. Workload A: Azure Cosmos DB; Workload B: Azure Cosmos DB

Question 15

A company stores customer records in a relational database table with fixed columns (CustomerID, Name, Email). They also store product reviews as JSON documents that may contain varying fields such as Rating, Comment, and optional Tags. Additionally, they store product images as JPEG files. Which of the following correctly orders these data types from most structured to least structured?

Accepted Answer

Relational table, JSON documents, image files. Relational tables enforce a fixed schema with predefined columns and data types, making them the most structured. JSON documents have a flexible schema where fields like Tags are optional, placing them in the middle. Image files are binary blobs with no inherent structure, making them the least structured. Option B correctly orders these from most structured (relational table) to least structured (image files).

Answer

JSON documents, relational table, image files

Answer

Image files, relational table, JSON documents

Answer

Relational table, image files, JSON documents