Interview Q&A

• Durable Functions allow stateful workflows in serverless apps.
• Enable orchestration, chaining, and long-running tasks without managing state

manually.

Example:

[FunctionName("OrchestratorFunction")]

public static async Task RunOrchestrator(

[OrchestrationTrigger] IDurableOrchestrationContext context)

{

wait context.CallActivityAsync("HelloActivity", "Tokyo");

wait context.CallActivityAsync("HelloActivity", "Seattle");

}

Answer: Use Durable Functions, Azure Storage, Cosmos DB, or Redis Cache. Serverless functions themselves are stateless by design.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

• Use Function.json or attributes in C# for retry policies.

[FunctionName("QueueRetryFunction")]

[FixedDelayRetry(3, "00:00:10")]

public static void Run([QueueTrigger("retryqueue")] string message,

ILogger log)

{

log.LogInformation($"Processing message: {message}");

}

Answer: Right-click the Function Project → Publish → Azure → Select Function App → Publish Supports slots, CI/CD, and zip deployment

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Function keys are authentication tokens used to control access to Azure Functions. Can be function-level or host-level.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Use Azure Functions Core Tools: func start Supports local storage emulator and debugging in Visual Studio.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Consumption Plan: Automatically scales out based on trigger events. Premium Plan: Provides pre-warmed instances for faster response and scaling. Dedicated App Service Plan: Manual scaling like a normal App Service. Q&A

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

• A trigger defines how and when a function is invoked.
• Examples: HTTP requests, queue messages, blob changes, timer events.
• Every function must have exactly one trigger.

Example (HTTP trigger):

[FunctionName("HttpTriggerFunction")]

public static IActionResult Run(

[HttpTrigger(AuthorizationLevel.Function, "get", "post")]

HttpRequest req,

ILogger log)

{

log.LogInformation("HTTP trigger executed.");

return new OkObjectResult("Hello from Azure Function!");
}

• Input bindings: Provide data to the function from external sources (e.g., queue

message, blob content).

• Output bindings: Send data from the function to external destinations (e.g., Cosmos

DB, Storage Queue).

Example:

[FunctionName("QueueToBlobFunction")]

public static void Run(

[QueueTrigger("myqueue")] string queueMessage,

[Blob("output-container/{rand-guid}.txt", FileAccess.Write)] out

string blobContent,

ILogger log)

{

log.LogInformation($"Processing queue message: {queueMessage}");

blobContent = queueMessage; // Write to blob
}

Answer: Yes. A function can have one trigger and multiple input/output bindings. Simplifies reading/writing from multiple sources in a single execution.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

• Use [BlobTrigger] for input or [Blob] for output.

Example (input blob):

[FunctionName("BlobProcessor")]

public static void Run(

[BlobTrigger("input-container/{name}")] Stream blobStream,

string name,

ILogger log)

{

log.LogInformation($"Processing blob: {name}");

}

Example (output blob):

[Blob("output-container/output.txt", FileAccess.Write)] out string

outputBlob

• Use [CosmosDBTrigger] for input and [CosmosDB] for output.

Example (input Cosmos DB trigger):

[FunctionName("CosmosDBTriggerFunction")]

public static void Run(

[CosmosDBTrigger(

databaseName: "MyDatabase",

collectionName: "MyCollection",

ConnectionStringSetting = "CosmosDBConnection",

LeaseCollectionName = "leases")] IReadOnlyList<Document>

input,

ILogger log)

{
foreach (var doc in input)
{

log.LogInformation($"Document received: {doc.Id}");

}
}

Example (output Cosmos DB binding):

[CosmosDB(

databaseName: "MyDatabase",

collectionName: "MyCollection",

ConnectionStringSetting = "CosmosDBConnection")] out dynamic

outputDoc

outputDoc = new { id = Guid.NewGuid(), Name = "New Item" };

Answer: Trigger: Invokes the function. Every function must have one trigger. Binding: Connects function inputs/outputs to external resources. Optional, can have multiple.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Remove manual SDK code for connecting to Azure services. Automatically serialize/deserialize data. Focus on business logic instead of plumbing.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: In Function attributes (C#) like [Blob], [QueueTrigger] Or in function.json for configuration settings: { "type": "queueTrigger", "direction": "in", "name": "myQueueItem", "queueName": "myqueue", "connection": "AzureWebJobsStorage" }

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Store secrets in Azure App Service Application Settings or Key Vault. Reference via Connection property in binding: [QueueTrigger("myqueue", Connection = "AzureWebJobsStorage")]

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Yes, using binding expressions like {name}, {rand-guid}, or {datetime}. Example (dynamic blob output): [Blob("container/{name}-{datetime}.txt", FileAccess.Write)] out string outputBlob

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Azure SQL Database is a fully managed relational database service on Azure. Provides automatic backups, patching, scaling, high availability, and security.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Azure Cosmos DB is a globally distributed, multi-model NoSQL database. Supports key-value, document, graph, and column-family data models. Provides automatic scaling, low latency, and global replication.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Feature Azure SQL Cosmos DB

Type Relational NoSQL, multi-model

Schema Fixed Schema-less

Scaling Vertical/Horizontal Horizontal, automatic

Consistenc

CID Multiple consistency levels (Strong, Eventual, etc.)

Use Case OLTP, structured

data

Global apps, unstructured data, IoT

• Use connection string in appsettings.json:

"ConnectionStrings": {

"DefaultConnection":

"Server=tcp:myserver.database.windows.net,1433;Initial
Catalog=MyDb;Persist Security Info=False;User
ID=myuser;Password=mypassword;MultipleActiveResultSets=False;Encrypt
=True;TrustServerCertificate=False;Connection Timeout=30;"
}

• Inject DbContext using Entity Framework Core:

builder.Services.AddDbContext<MyDbContext>(options =>

options.UseSqlServer(builder.Configuration.GetConnectionString("Defa

ultConnection")));

Answer: SQL Authentication: Username and password. Azure Active Directory (AAD) authentication. Managed Identity: Use Azure App Service identity to connect without storing credentials.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Serverless compute tier auto-scales based on workload and pauses during inactivity. Cost-efficient for intermittent workloads.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: Use Azure Data Migration Assistant (DMA). Use bacpac import/export. Use SQL Server Management Studio (SSMS) deploy options.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.

Answer: DTU (Database Transaction Unit): Bundled measure of CPU, memory, IOPS. vCore: Separate allocation of virtual cores, memory, and storage. vCore allows flexible scaling and cost optimization.

What interviewers expect

• A clear definition tied to Azure in Microsoft Azure projects
• Trade-offs (performance, maintainability, security, cost)
• When you would and would not use it in production

Real-world example

In a production Microsoft Azure application, teams apply this when handling user-facing features or integration boundaries. For example, you might use it during a sprint where reliability and observability matter—logging metrics, validating edge cases, and documenting the decision in an ADR so future developers understand why the approach was chosen.

How to explain in the interview

1. Define the concept in one or two sentences.
2. Context — where it fits in Microsoft Azure architecture.
3. Example — a specific project, bug, or performance win.
4. Trade-off — what you gain vs what you sacrifice.

Tip: Practice aloud on Toolliyo mock interview or the Interview Q&A section before your real interview.