DP-900 Describe core data concepts Practice Test 2 — 15 Questions

Question 1

Refer to the exhibit. You are analyzing storm event data in Azure Data Explorer. The KQL query returns the top 5 event types by count in Texas. However, the results show event types with very low counts (e.g., 'Volcanic Ash' with 2 events). What is the most likely reason for this?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The state filter is case-sensitive and the actual state value differs.. Azure Data Explorer (ADX) is case-sensitive by default in string comparisons. The 'where' clause filters on the 'state' column, and if the actual value in the data is 'texas' (lowercase) or 'TEXAS' (uppercase), the filter 'state == "Texas"' will not match any rows. This causes the query to return results from all states, including those with very low event counts like 'Volcanic Ash' from other regions.

Answer

The query has a syntax error.

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The 'take' operator limits the number of events, not the number of types.

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The 'summarize' operator cannot be used with 'where'.

Question 2

Refer to the exhibit. You create an Azure Policy to deny virtual machines that are not using approved SKUs. After assigning the policy to a subscription, a user tries to create a VM with SKU 'Standard_DS2_v2' and the creation is allowed. What is the most likely reason?

Accepted Answer

The alias 'Microsoft.Compute/virtualMachines/sku.name' is incorrect; the correct alias is 'Microsoft.Compute/virtualMachines/sku'.. The alias 'Microsoft.Compute/virtualMachines/sku.name' is invalid. In Azure Policy, the alias for the SKU property of a virtual machine is 'Microsoft.Compute/virtualMachines/sku'. The 'name' child property is not part of the alias path. Using an incorrect alias means the policy rule never evaluates the intended property, so the deny effect never triggers, allowing any SKU to be created.

Answer

The policy is not assigned to the resource group where the VM is created.

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The field type 'Microsoft.Compute/virtualMachines' is incorrect.

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The policy rule does not specify a deny effect.

Question 3

Which TWO of the following are characteristics of structured data?

Accepted Answer

Data is organized in rows and columns. Structured data is defined by its organization into rows and columns, typically within a relational database or spreadsheet, where each column represents a specific attribute and each row a record. This tabular format enables efficient querying, sorting, and aggregation using SQL. Option B correctly identifies this core characteristic.

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Data uses tags or markers to separate elements

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Data is stored in Azure Cosmos DB

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Data has no predefined schema

Question 4

Which THREE of the following are benefits of using Azure Data Lake Storage Gen2?

Accepted Answer

Cost-effective for storing petabytes of data. Option A is correct because Azure Data Lake Storage Gen2 is built on Blob Storage and is designed to be cost-effective for storing petabytes of data, offering tiered storage and low-cost capacity for massive datasets. Option B is correct because ADLS Gen2 supports POSIX-compliant access control lists (ACLs), enabling fine-grained, file- and directory-level permissions that are essential for big data analytics workloads. Option E is correct because ADLS Gen2 provides a hierarchical namespace, which organizes objects into directories and enables efficient directory-level operations such as atomic renames and deletes. Option C is incorrect because ADLS Gen2 is not a NoSQL document store; that role belongs to Azure Cosmos DB. Option D is incorrect because ADLS Gen2 is a storage service and does not include an integrated data transformation engine; transformation is handled by separate services such as Azure Data Factory, Azure Databricks, or Azure Synapse Analytics.

Answer

Built-in NoSQL document store

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Integrated data transformation engine

Question 5

Your organization is migrating its on-premises SQL Server databases to Azure. The databases include a mix of operational (OLTP) and analytical (OLAP) workloads. For the OLTP databases, you need high availability and automated failover to a secondary region. For the OLAP databases, you need to support large-scale analytic queries with columnstore indexes and the ability to pause compute to save costs. Which Azure SQL deployment options should you choose for each workload type?

Accepted Answer

Azure SQL Database (geo-replication) for OLTP; Azure Synapse Analytics (dedicated SQL pool) for OLAP. Azure SQL Database with active geo-replication provides high availability and automated failover to a secondary region for OLTP workloads, while Azure Synapse Analytics (dedicated SQL pool) supports large-scale analytic queries with columnstore indexes and allows pausing compute to save costs, meeting the OLAP requirements.

Answer

Azure SQL Managed Instance for both

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SQL Server on Azure Virtual Machines for both

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Azure SQL Database Hyperscale for OLTP; Azure SQL Database Serverless for OLAP

Question 6

A financial services company needs to store transaction records for 7 years to comply with regulatory requirements. The data is rarely accessed after the first month but must be available for audit within 24 hours. The storage solution must minimize cost while meeting compliance. Which Azure storage tier should you use for data older than one month?

Accepted Answer

Cool tier. The Cool tier is designed for data that is infrequently accessed but must be available quickly when needed, with a 30-day minimum storage duration and lower storage cost than Hot tier. Since the data is rarely accessed after the first month but must be retrievable within 24 hours for audits, Cool tier meets both the cost and availability requirements without the higher cost of Hot tier or the retrieval delay of Archive tier.

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Premium tier

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Archive tier

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Hot tier

Question 7

A company stores customer names, addresses, and order history. They need to perform complex queries that join customer and order data. Which type of data store is most appropriate for this scenario?

Accepted Answer

Relational database. A relational database (e.g., Azure SQL Database) is most appropriate because the scenario requires joining customer and order data via complex queries. Relational databases enforce a fixed schema with tables, primary keys, and foreign keys, enabling efficient JOIN operations using SQL. This structure ensures data integrity and supports ACID transactions, which are essential for accurate order history and customer records.

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Key-value store

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Document database

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Graph database

Question 8

A retail company captures real-time sensor data from IoT devices to detect anomalies and predict equipment failures. The data must be processed immediately as it arrives. Which type of data processing workload best describes this scenario?

Accepted Answer

Streaming processing. B is correct because streaming processing is designed for continuous, real-time data ingestion and immediate analysis, which matches the requirement to process sensor data as it arrives. Technologies like Azure Stream Analytics or Apache Kafka enable low-latency processing of IoT data streams to detect anomalies and predict failures without batching.

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Batch processing

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Online transaction processing (OLTP)

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Data warehousing

Question 9

Which classification of data describes information that has a fixed schema and is organized into rows and columns, such as data found in a relational database table?

Accepted Answer

Structured data. Structured data is defined by a fixed schema, where each data element adheres to a predefined data type and relationship, organized into rows and columns. This is the fundamental model of a relational database table, such as those in Azure SQL Database or SQL Server, where constraints like primary keys and foreign keys enforce the schema.

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Unstructured data

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Semi-structured data

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Transformed data

Question 10

A logistics company stores shipping waybill data as JSON documents. Each document contains fields like 'shipmentId', 'destination', and 'items', but the number of items and the fields within each item can vary between shipments. Which category best describes this type of data?

Accepted Answer

Semi-structured data. JSON documents with varying fields and nested structures like 'items' that differ between shipments are a classic example of semi-structured data. Unlike structured data with a fixed schema, semi-structured data uses tags or markers (like JSON key-value pairs) to separate data elements, allowing for flexibility in the number and type of fields per record. This aligns with the DP-900 definition of semi-structured data, which includes formats such as JSON, XML, and Parquet.

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Operational data

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Unstructured data

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Structured data

Question 11

A consulting firm collects client information in two forms: a spreadsheet with columns for Name, Address, and Phone Number, and audio recordings of client meetings. Which of the following statements correctly categorizes these data types?

Accepted Answer

The spreadsheet data is structured, and the audio recordings are unstructured.. The spreadsheet data with columns for Name, Address, and Phone Number has a predefined schema (rows and columns), making it structured data. Audio recordings are binary files with no inherent schema or organization, fitting the definition of unstructured data. Option C correctly pairs these classifications.

Answer

Both the spreadsheet data and the audio recordings are examples of structured data.

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The spreadsheet data is structured, and the audio recordings are semi-structured.

Answer

The spreadsheet data is semi-structured, and the audio recordings are unstructured.

Question 12

A company operates an online store that processes customer orders. When a customer places an order, the system must immediately reduce the inventory count for the purchased items and record the order details. At the end of each month, the company runs reports that aggregate sales data over the past month to analyze trends. Which type of data processing workload best describes the order placement activity?

Accepted Answer

Transactional processing. Order placement requires immediate inventory reduction and order recording, which demands ACID (Atomicity, Consistency, Isolation, Durability) guarantees. This is a classic transactional processing workload, typically handled by OLTP (Online Transaction Processing) systems like SQL Server or Azure SQL Database, ensuring data integrity even under concurrent access.

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Analytical processing

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Batch processing

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Stream processing

Question 13

A healthcare provider stores patient admission data in a relational database table with columns for PatientID, Name, and AdmissionDate. Progress notes are stored as free-text documents. Lab results are stored as XML files that contain varying fields depending on the test type. Which of the following correctly categorizes these three data types in order: relational table, progress notes, lab results?

Accepted Answer

Structured, Unstructured, Semi-structured. The relational table with PatientID, Name, and AdmissionDate enforces a fixed schema with defined data types, making it structured data. Progress notes as free-text documents have no predefined structure or schema, classifying them as unstructured data. Lab results in XML files use tags to organize data but allow varying fields per test type, which is the hallmark of semi-structured data. Option A correctly maps these in order: structured, unstructured, semi-structured.

Answer

Structured, Semi-structured, Unstructured

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Semi-structured, Unstructured, Structured

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Unstructured, Structured, Semi-structured

Question 14

A manufacturing company collects sensor data from equipment on the factory floor. The data is generated continuously and must be processed immediately to detect anomalies and trigger alerts. Which type of data processing workload best describes this scenario?

Accepted Answer

Stream processing. B is correct because the scenario requires continuous data ingestion and immediate processing to detect anomalies and trigger alerts, which is the defining characteristic of stream processing. Technologies like Azure Stream Analytics or Apache Kafka are designed to handle unbounded data streams with low-latency processing, unlike batch processing which operates on static datasets at scheduled intervals.

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Batch processing

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Transactional processing

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Analytical processing

Question 15

A company collects customer feedback in three forms: a structured table with customer ID and rating (1-5), free-text comments, and audio recordings of phone calls. Which of the following correctly orders these data from least structured to most structured?

Accepted Answer

Audio recordings, free-text comments, structured table. Ly orders the data from least structured to most structured. Audio recordings are unstructured (no schema). Free-text comments are also unstructured (no fixed format in DP-900 classification). The structured table has defined columns and data types. Thus, the order is audio (unstructured), free-text (unstructured), structured table.

Answer

Structured table, free-text comments, audio recordings

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Free-text comments, structured table, audio recordings

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Audio recordings, structured table, free-text comments