AZ-204 Practice Test 49 — 15 Questions

Question 1

You are designing a solution that writes millions of small log records (each 200 bytes) to Azure Blob Storage. The logs are written every second, always appended to a single file. The file must be read periodically by a batch process that reads the entire file. You need to maximize write throughput and minimize storage costs. Which blob type and access strategy should you choose?

Accepted Answer

Use Append blobs and write each log entry as an append block. Append blobs are optimized for append operations, making them ideal for writing millions of small log records sequentially to a single file. Each log entry is written as an append block, which provides high throughput for append-heavy workloads. Append blobs also minimize storage costs because they store data in a single blob without the overhead of managing multiple blobs or pages.

Answer

Use Block blobs and append the data to a single blob

Answer

Use Page blobs and write each log entry to a page

Answer

Use Block blobs and create a new blob for each log entry

Question 2

You are designing an Azure Table Storage table to store temperature readings from IoT devices. Each reading includes a device ID (string), timestamp (datetime), temperature value, and location. You need to optimize the table design for this query: "Retrieve all temperature readings for a specific device ID within a given one-hour time range." The query must be efficient and minimize partition scans. Which PartitionKey and RowKey combination should you use?

Accepted Answer

PartitionKey = device ID, RowKey = timestamp (formatted as inverted ticks). Option A is correct because using device ID as the PartitionKey ensures all readings for a specific device are in the same partition, allowing efficient point queries. Using timestamp formatted as inverted ticks (e.g., DateTime.MaxValue.Ticks - DateTime.UtcNow.Ticks) as the RowKey enables range queries within a one-hour window by leveraging the lexicographic ordering of RowKey values, minimizing partition scans.

Answer

PartitionKey = timestamp (rolled up to day), RowKey = device ID

Answer

PartitionKey = location, RowKey = device ID

Answer

PartitionKey = device ID + timestamp (composite), RowKey = empty

Question 3

You are developing a C# application that stores sensitive documents in Azure Blob Storage. The application needs to generate a time-limited shared access signature (SAS) that allows a client to only read and list blobs in a specific container. The SAS must be valid for exactly 1 hour from the current time. Which code snippet correctly creates the SAS? (Assume the BlobServiceClient and BlobContainerClient are properly initialized.)

Accepted Answer

var sasBuilder = new BlobSasBuilder { BlobContainerName = container.Name, Permissions = "rl", ExpiresOn = DateTimeOffset.UtcNow.AddHours(1) }; var sasUri = container.GenerateSasUri(sasBuilder);. Option A is correct because it creates a `BlobSasBuilder` with the container name, permissions set to "rl" (read and list), and an expiration time of exactly 1 hour from the current UTC time. The `GenerateSasUri` method then produces a SAS URI that grants the specified permissions for the container. This matches the requirement for a time-limited SAS that allows only read and list operations on blobs in the container.

Answer

var sasBuilder = new BlobSasBuilder { Permissions = "r", ExpiresOn = DateTimeOffset.UtcNow.AddHours(1) }; var sasUri = container.GenerateSasUri(sasBuilder);

Answer

var sasToken = container.GetSasToken(permissions: "rl", duration: TimeSpan.FromHours(1));

Answer

var sasBuilder = new BlobSasBuilder { Permissions = "rl", StartsOn = DateTimeOffset.UtcNow, ExpiresOn = DateTimeOffset.UtcNow.AddHours(1) }; var sasUri = container.GenerateSasUri(sasBuilder);

Question 4

You need to allow a client application to read a specific blob from Azure Blob Storage for one hour, without exposing your storage account key. Which approach should you use?

Accepted Answer

Generate a shared access signature (SAS) URI with read permission and expiry of one hour. Option B is correct because a shared access signature (SAS) URI allows you to delegate limited access (read permission) to a specific blob for a defined time period (one hour) without exposing your storage account key. The SAS token is generated using the account key but does not reveal it, ensuring secure, time-bound access.

Answer

Provide the storage account access key to the client

Answer

Use Azure RBAC to grant the client the Storage Blob Data Reader role for one hour

Answer

Make the blob publicly accessible for one hour using a stored access policy

Question 5

You need to store large binary files (up to 2 GB) that are frequently overwritten in place (entire file replaced). You want to minimize storage cost and write latency. Which Azure Blob Storage type should you use?

Accepted Answer

Block Blob. Block blobs are optimized for storing large binary files (up to ~4.75 TB) and support high-throughput uploads via PutBlock and PutBlockList operations. They allow overwriting an entire blob by uploading a new set of blocks, which minimizes write latency compared to page blobs that require sector-aligned writes. Block blobs also offer lower storage cost than page blobs, making them the best choice for frequently overwritten large files.

Answer

Page Blob

Answer

Append Blob

Answer

Archive Blob

Question 6

You need to store billions of small log entries (each ~200 bytes) written in chronological order from multiple producers. The logs are read sequentially in bulk once per day. You need to maximize write throughput and minimize storage costs. Which Azure Storage solution should you choose?

Accepted Answer

Append Blob in Blob Storage. Append Blob in Blob Storage is optimized for append operations, making it ideal for writing small log entries in chronological order from multiple producers. It provides high write throughput because each append operation is atomic and can be performed concurrently, and it minimizes storage costs by storing data in a cost-effective blob tier without the overhead of indexing or metadata management required by other solutions.

Answer

Block Blob in Blob Storage with high block count

Answer

Azure Data Lake Storage Gen2 with hierarchical namespace

Answer

Azure Files with SMB protocol

Question 7

You need to store temperature readings from IoT devices in Azure Table Storage. Each reading includes a device ID (string), timestamp (datetime), temperature value, and location. You must optimize for the query: "Retrieve all temperature readings for a specific device ID within a given one-hour time range." Which PartitionKey and RowKey combination should you use?

Accepted Answer

PartitionKey = DeviceId, RowKey = Timestamp. Option A is correct because Azure Table Storage queries are most efficient when the PartitionKey and RowKey are chosen to match the query pattern. By using DeviceId as the PartitionKey, all readings for a specific device are stored in the same partition, enabling fast partition-level scans. Using Timestamp as the RowKey allows efficient range queries within a one-hour window using RowKey comparisons, which is the optimal design for time-range queries on a single device.

Answer

PartitionKey = Location, RowKey = DeviceId

Answer

PartitionKey = Temperature, RowKey = Timestamp

Answer

PartitionKey = DeviceId + Timestamp, RowKey = empty

Question 8

You need to store large amounts of unstructured data (images and videos) that are accessed rarely (a few times per year) but must be available within minutes when requested. The data must be geo-redundant for disaster recovery. You want to minimize storage costs. Which storage tier and redundancy option should you choose?

Accepted Answer

Cool storage tier with geo-redundant storage (GRS). The Cool storage tier is designed for data that is infrequently accessed (a few times per year) and stored for at least 30 days, offering lower storage costs than Hot tier while still providing low-latency retrieval within minutes. Geo-redundant storage (GRS) replicates data to a paired secondary region, ensuring disaster recovery with geo-redundancy. This combination meets the requirements of rare access, minutes-availability, geo-redundancy, and minimal cost.

Answer

Hot storage tier with geo-redundant storage (GRS)

Answer

Archive storage tier with read-access geo-redundant storage (RA-GRS)

Answer

Premium storage tier with local redundant storage (LRS)

Question 9

You need to store millions of small log entries (each <1 KB) per day from an IoT device. The logs are rarely read. Which storage solution is most cost-effective?

Accepted Answer

Azure Blob Storage Block Blob. Azure Blob Storage Block Blob is the most cost-effective solution for storing millions of small log entries (<1 KB) that are rarely read because it offers extremely low storage costs per GB, supports high-throughput ingestion, and is optimized for large-scale, append-oriented workloads. Block blobs can be stored in the 'Cool' or 'Archive' access tier to further reduce costs, and they can be efficiently batched into larger blocks (up to 100 MB per block) to minimize transaction costs.

Answer

Azure SQL Database

Answer

Azure Table Storage

Answer

Azure Files

Question 10

You need to store terabytes of archival data that must be retained for 10 years. The data is accessed once or twice per year. You need to minimize storage costs. Which Azure Storage tier should you use?

Accepted Answer

Archive. The Archive tier is designed for data that is rarely accessed (a few times per year or less) and has a flexible retrieval latency of several hours, making it ideal for long-term retention of terabytes of archival data for 10 years at the lowest storage cost. It offers the lowest per-GB storage price among Azure Blob Storage tiers, directly meeting the requirement to minimize costs for infrequently accessed data.

Answer

Cool

Answer

Hot

Answer

Premium

Question 11

Your company stores backup files in an Azure Blob Storage account. These files are written once and then need to be retained for 7 years. During the first year, the files are accessed weekly. After the first year, they are accessed rarely (once per month). You want to minimize storage costs. Which combination of access tiers and lifecycle management should you apply?

Accepted Answer

Store in Cool tier and move to Archive after 1 year.. Option B is correct because it minimizes costs by storing files in the Cool tier from the start (matching the initial weekly access pattern) and then moving them to the Archive tier after one year when access drops to monthly. The Cool tier offers lower storage cost than Hot for infrequent access, and the Archive tier provides the lowest storage cost for data that is rarely accessed and can tolerate a retrieval latency of up to 15 hours. This lifecycle policy aligns with the 7-year retention requirement without incurring unnecessary early deletion charges or rehydration costs.

Answer

Store in Hot tier and move to Cool after 1 year, then to Archive after 7 years.

Answer

Store directly in Archive tier and rehydrate to Cool when needed for access.

Answer

Store in Hot tier and move to Archive after 90 days.

Question 12

Your IoT solution generates billions of small telemetry entries (each ~100 bytes). Data is written once and rarely updated. You need to run analytical queries on the last 30 days of data daily, scanning large ranges by timestamp, requiring sub-second response times. You want the lowest storage cost. Which Azure Storage solution should you use?

Accepted Answer

Azure Table Storage. Azure Table Storage is correct because it is a NoSQL key-value store optimized for high-volume, low-cost storage of structured data like telemetry entries. It supports efficient range queries on the partition key (e.g., timestamp) and row key, enabling sub-second scans of large date ranges. Its storage cost is the lowest among Azure storage options for this workload, as it charges only for consumed capacity with no minimum throughput commitments.

Answer

Azure Blob Storage

Answer

Azure Cosmos DB

Answer

Azure Data Lake Storage

Question 13

An application stores customer invoices in Azure Blob Storage. Deleted blobs must be recoverable for 14 days. What should be enabled? The design must avoid adding custom operational scripts.

Accepted Answer

Blob soft delete with a 14-day retention period. Blob soft delete protects against accidental deletion by retaining deleted blobs for a specified retention period. Enabling it with a 14-day retention period allows recovery of deleted invoices within that window without custom scripts, meeting the requirement exactly.

Answer

Archive access tier

Answer

Static website hosting

Answer

Immutable blob legal hold

Question 14

You design an application that writes millions of small sensor readings (each ~100 bytes) to Azure Blob Storage. The data is appended to files every minute and after 7 days it is archived for compliance. You need to minimize write costs and storage costs. Which blob type and tier strategy should you use?

Accepted Answer

Append blobs with Hot tier and a lifecycle rule to move to Archive after 7 days.. Append blobs are optimized for append operations, making them ideal for continuously adding small sensor readings without rewriting existing data, which minimizes write costs. Moving the blobs to the Archive tier after 7 days via a lifecycle rule reduces storage costs for compliance data, as Archive is the lowest-cost tier for infrequently accessed data.

Answer

Block blobs with Hot tier and a lifecycle rule to move to Cool after 7 days.

Answer

Page blobs with Premium tier.

Answer

Append blobs with Cool tier and no lifecycle rule.

Question 15

You need to store large files that are written once and then frequently read for the first 30 days. After 30 days, the files are rarely accessed (once or twice per year) but must remain available for 5 years. You want to minimize storage costs. Which storage tier and lifecycle management rule should you apply?

Accepted Answer

Hot tier with a lifecycle rule to move to Cool after 30 days. Option A is correct because the Hot tier is optimized for frequent reads, and the lifecycle rule moves data to the Cool tier after 30 days when access drops, balancing performance and cost. After 30 days, the files are rarely accessed, so moving them to Cool (not Archive) keeps them available for occasional reads without the high retrieval costs and latency of Archive. This minimizes storage costs while meeting the 5-year retention requirement.

Answer

Cool tier with a lifecycle rule to move to Archive after 30 days

Answer

Hot tier with a lifecycle rule to move to Archive after 30 days

Answer

Archive tier with a lifecycle rule to move to Cool after 30 days