DP-900 Practice Test 49 — 15 Questions

Question 1

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 2

Refer to the exhibit. This ARM template snippet is used to deploy which Azure resource?

Accepted Answer

Azure SQL Database server. Option A is correct because the properties include serverName, administratorLogin, etc., which are for an Azure SQL Database server. Option B is wrong because Azure SQL Managed Instance deployment uses different properties. Option C is wrong because Azure Database for MySQL has different properties. Option D is wrong because Azure Synapse Analytics workspace has different properties.

Answer

Azure Database for MySQL server

Answer

Azure SQL Managed Instance

Answer

Azure Synapse Analytics workspace

Question 3

A manufacturing company collects sensor data from thousands of IoT devices. Each reading contains a device ID, timestamp, value, and device-specific measurement fields. The company needs to analyze the data in real time to detect anomalies and trigger alerts. They also need to store the same data for historical batch analysis to identify long-term trends. Which architecture pattern best describes this combination of data processing approaches?

Accepted Answer

Lambda architecture. The Lambda architecture is the correct pattern because it combines both stream processing for real-time anomaly detection and alerting, and batch processing for historical analysis of long-term trends. This architecture uses a speed layer for low-latency stream processing (e.g., Apache Kafka, Azure Stream Analytics) and a batch layer for comprehensive, accurate historical computations (e.g., Azure Data Lake, Apache Spark). The serving layer then merges results from both paths to provide a unified view.

Answer

Batch processing only

Answer

Stream processing only

Answer

Data lake

Question 4

A company collects temperature readings from IoT sensors every second. Each reading includes a timestamp, sensor ID, and temperature value. The data is used for real-time monitoring and historical trend analysis. Which type of data is this most likely classified as?

Accepted Answer

Structured data. The data consists of timestamp, sensor ID, and temperature value, each with a defined data type and relationship, fitting a tabular schema (rows and columns) typical of relational databases. This structured format enables efficient querying for real-time monitoring and historical trend analysis using SQL-based systems like Azure SQL Database or Azure Synapse Analytics.

Answer

Semi-structured data

Answer

Unstructured data

Answer

Streaming data

Question 5

A company is building a data lake and collects data from three sources: (1) a relational database exporting CSV files with fixed columns for customer records, (2) API responses stored as JSON files with varying fields for product reviews, and (3) scanned handwritten notes stored as TIFF images. Which statement correctly categorizes these data by structure type?

Accepted Answer

1: structured, 2: semi-structured, 3: unstructured. Option A is correct because CSV files from a relational database have a fixed schema (rows and columns), making them structured data. JSON files from API responses with varying fields are semi-structured, as they use tags/keys to organize data without a rigid schema. TIFF images of handwritten notes are unstructured, lacking a predefined data model or organization.

Answer

1: semi-structured, 2: structured, 3: unstructured

Answer

1: structured, 2: unstructured, 3: semi-structured

Answer

1: unstructured, 2: semi-structured, 3: structured

Question 6

A bank's online transaction processing system records every withdrawal and deposit in a database. The bank also runs a monthly report that summarizes total transactions per customer. Which statement correctly identifies these two workloads?

Accepted Answer

The transaction recording is OLTP, and the monthly report is OLAP.. The transaction recording system is an OLTP (Online Transaction Processing) workload because it handles individual, real-time transactions (withdrawals and deposits) with high concurrency and low latency. The monthly report summarizing total transactions per customer is an OLAP (Online Analytical Processing) workload because it aggregates historical data for reporting and analysis, typically using batch processing or columnar storage. Option B correctly pairs each workload with its appropriate processing type.

Answer

Both workloads are OLTP.

Answer

The transaction recording is OLAP, and the monthly report is OLTP.

Answer

Both workloads are OLAP.

Question 7

A company processes sales transactions in real-time from a retail website. Each transaction is recorded as a row in a relational database. Additionally, the company stores weekly sales reports as PDF files. Which statement correctly describes these data types?

Accepted Answer

Transactions are structured, reports are unstructured.. Transactions are structured because they are stored as rows in a relational database, which imposes a fixed schema with defined columns and data types. Weekly sales reports as PDF files are unstructured because they lack a predefined data model and cannot be easily queried using SQL without additional processing. Option B correctly identifies this distinction.

Answer

Transactions are unstructured, reports are semi-structured.

Answer

Both are structured because they are files.

Answer

Both are unstructured because they are digital.

Question 8

A company stores customer orders in a database. Each order has an OrderID (integer), CustomerName (text), OrderDate (date), and a JSON column for order details that contains varying fields such as discount codes or gift messages. Which statement best describes the data types in this table?

Accepted Answer

The table stores both structured and semi-structured data.. The table includes structured columns (OrderID integer, CustomerName text, OrderDate date) and a JSON column for order details, which stores semi-structured data because JSON allows flexible schemas with varying fields like discount codes or gift messages. This combination of fixed-schema columns and a schema-less JSON column means the table holds both structured and semi-structured data, making option B correct.

Answer

The table stores only structured data.

Answer

The table stores only unstructured data.

Answer

The table stores only semi-structured data.

Question 9

A company stores customer orders in a relational database. The database enforces rules that every order must have a unique order number and must be linked to an existing customer record. This enforcement of rules to ensure accuracy and consistency is an example of which data concept?

Accepted Answer

Data integrity. Data integrity refers to the enforcement of rules that ensure the accuracy, consistency, and reliability of data throughout its lifecycle. In this scenario, the relational database enforces entity integrity (unique order numbers) and referential integrity (linking orders to existing customer records), which are core mechanisms for maintaining data correctness.

Answer

Data schema

Answer

Data redundancy

Answer

Data latency

Question 10

A data engineer loads raw log files into a storage system. The structure of the data is interpreted at the time of reading, allowing queries to apply schema on the fly without preprocessing. This approach is best described as:

Accepted Answer

Schema-on-read. Schema-on-read means the data is stored in its raw, unstructured form, and the schema is applied dynamically when the data is queried. This is exactly what happens when raw log files are loaded into a storage system like Azure Data Lake Storage and queried with tools like Azure Synapse Serverless SQL or Apache Spark, which infer the schema at query time without requiring preprocessing.

Answer

Schema-on-write

Answer

Data warehouse

Answer

Data virtualization

Question 11

A company stores customer information in a table with columns CustomerID, Name, Address, and PhoneNumber. Every row has values for all these columns, and the data follows a fixed schema. Which type of data does this represent?

Accepted Answer

Structured data. Structured data conforms to a fixed schema where each row has the same columns and data types. The table with CustomerID, Name, Address, and PhoneNumber, where every row contains values for all columns, perfectly fits this definition. This is typical of relational database tables (e.g., in Azure SQL Database) where the schema is enforced at the table level.

Answer

Unstructured data

Answer

Semi-structured data

Answer

Streaming data

Question 12

Which TWO features are available in Azure SQL Database to improve performance without changing application code?

Accepted Answer

Automatic tuning. Options A and D are correct. Query Store tracks query performance and helps identify regressions. Automatic tuning uses the database engine to implement index and query plan changes. Option B is wrong because read replicas require application changes to route read traffic. Option C is wrong because elastic pools are for managing multiple databases, not performance tuning. Option E is wrong because columnstore indexes require table schema changes.

Answer

Columnstore indexes

Answer

Read replicas

Answer

Elastic pools

Question 13

A company receives customer order data from its online store in a CSV file. Each line contains fields like OrderID, CustomerName, Product, Quantity, and OrderDate. This data is best described as:

Accepted Answer

Structured data. A is correct because the CSV file contains data that conforms to a strict tabular schema with predefined columns (OrderID, CustomerName, Product, Quantity, OrderDate) and consistent data types per column. This rigid, row-and-column format with a fixed schema is the defining characteristic of structured data, which can be directly loaded into a relational database or Azure SQL Database without transformation.

Answer

Semi-structured data

Answer

Unstructured data

Answer

Transactional data

Question 14

A company stores customer data in a SQL table with fixed columns (CustomerID, Name, Email, SignupDate). They also store product images as JPEG files and application logs as JSON documents. Which of the following correctly classifies each data type?

Accepted Answer

SQL table: structured, JPEG: unstructured, JSON: semi-structured. Option A is correct because a SQL table with fixed columns enforces a rigid schema, making it structured data. JPEG files are binary blobs with no internal schema, classifying them as unstructured. JSON documents use key-value pairs with flexible schemas, which is the definition of semi-structured data.

Answer

SQL table: structured, JPEG: semi-structured, JSON: unstructured

Answer

SQL table: semi-structured, JPEG: unstructured, JSON: structured

Answer

SQL table: unstructured, JPEG: structured, JSON: semi-structured

Question 15

A company stores customer orders in a relational database that handles many small transactions (inserts, updates, deletes) throughout the day. Separately, they maintain a data warehouse that is used for complex aggregations and historical trend analysis. Which statement correctly describes these two workloads?

Accepted Answer

The first system is an OLTP workload; the second is an OLAP workload.. The first system handles many small, concurrent transactions (inserts, updates, deletes) typical of an Online Transaction Processing (OLTP) workload, optimized for ACID compliance and fast query response. The second system is an Online Analytical Processing (OLAP) workload, designed for complex aggregations and historical trend analysis using columnar storage and star schemas. This distinction is fundamental in data architecture, where OLTP systems prioritize write performance and OLAP systems prioritize read performance for large-scale analytics.

Answer

Both systems are OLTP workloads because they store customer orders.

Answer

The first system is an OLAP workload; the second is an OLTP workload.

Answer

Both systems are OLAP workloads because they both involve data storage.