Interview Q&A

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

Real-world example (ShopNest)

Order-paid events go to Service Bus; an Azure Function sends the confirmation email asynchronously.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

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

Real-world example (ShopNest)

Order-paid events go to Service Bus; an Azure Function sends the confirmation email asynchronously.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short 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

Real-world example (ShopNest)

Order-paid events go to Service Bus; an Azure Function sends the confirmation email asynchronously.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Input bindings: Provide data to the function from external sources (e.g., queue message, blob content).

Explain a bit more

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

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

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

Real-world example (ShopNest)

Order-paid events go to Service Bus; an Azure Function sends the confirmation email asynchronously.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: 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

Real-world example (ShopNest)

Product images upload to Azure Blob Storage; the DB only stores the blob URL.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: 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) {

Example code

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" };

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

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

Real-world example (ShopNest)

Order-paid events go to Service Bus; an Azure Function sends the confirmation email asynchronously.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short 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" }

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

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

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short 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

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Feature Azure SQL Cosmos DB Type Relational NoSQL, multi-model Schema Fixed Schema-less Scaling Vertical/Horizontal Horizontal, automatic Consistenc ACID Multiple consistency levels (Strong, Eventual, etc.) Use Case OLTP, structured data Global apps, unstructured data, IoT

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: 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 =>…

Explain a bit more

options.UseSqlServer(builder.Configuration.GetConnectionString("Defa ultConnection")));

Example code

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")));

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

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

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

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

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use ADO.NET connection pooling (default in .NET). Ensure DbContext is scoped per request in ASP.NET Core.

Example code

services.AddDbContext<MyDbContext>(options => options.UseSqlServer(connectionString));

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Enable Transparent Data Encryption (TDE). Configure firewall rules and VNet integration. Use AAD authentication or Managed Identity. Enable Advanced Threat Protection.

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: SQL (Core) API MongoDB API Cassandra API Gremlin (Graph) API Table API

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use QueryDefinition and FeedIterator with MaxItemCount. var query = new QueryDefinition("SELECT * FROM c"); var iterator = container.GetItemQueryIterator<MyItem>(query, requestOptions: new QueryRequestOptions { MaxItemCount = 10 }); while (iterator.HasMoreResults) { foreach (var item in await iterator.ReadNextAsync()) { Console.WriteLine(item.Id); } }

Example code

Use QueryDefinition and FeedIterator with MaxItemCount. var query = new QueryDefinition("SELECT * FROM c");
var iterator = container.GetItemQueryIterator<MyItem>(query,
requestOptions: new QueryRequestOptions { MaxItemCount = 10 }); while (iterator.HasMoreResults) {
foreach (var item in await iterator.ReadNextAsync())
{ Console.WriteLine(item.Id); }
}

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Cosmos DB supports Strong, Bounded Staleness, Session, Consistent Prefix, Eventual. Set consistency when creating CosmosClient: var clientOptions = new CosmosClientOptions

Example code

{ ConsistencyLevel = ConsistencyLevel.Session }; var cosmosClient = new CosmosClient(endpointUri, primaryKey, clientOptions);

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Automatic backups every 4 hours (retention 7–30 days depending on config). Restore using point-in-time restore in Azure Portal or via CLI.

Real-world example (ShopNest)

ShopNest on Azure typically uses App Service + SQL Database + Blob Storage + Application Insights for monitoring.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Secrets: Strings, passwords, API keys, connection strings Keys: Cryptographic keys for encryption/decryption (RSA, EC) Certificates: SSL/TLS or client certificates

Real-world example (ShopNest)

Connection strings and payment keys live in Key Vault—not in source control or plain appsettings on disk.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Use Azure.Extensions.AspNetCore.Configuration.Secrets package to load secrets into IConfiguration. var builder = new ConfigurationBuilder() .AddAzureKeyVault(new Uri(" new DefaultAzureCredential()); var configuration = builder.Build();

Example code

var secretValue = configuration["MySecret"];

Real-world example (ShopNest)

Connection strings and payment keys live in Key Vault—not in source control or plain appsettings on disk.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Configure Access Policies in Azure Portal or via Azure CLI. Assign roles: Get → read secrets List → enumerate secrets Set → update secrets Use Managed Identity for apps instead of storing credentials.

Real-world example (ShopNest)

Connection strings and payment keys live in Key Vault—not in source control or plain appsettings on disk.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.

Short answer: Enable Managed Identity on your App Service or Function App. Grant Key Vault access policy to the identity. Access secrets without storing credentials: var client = new SecretClient(new Uri(" new DefaultAzureCredential()); KeyVaultSecret secret = client.GetSecret("MySecret");

Example code

string value = secret.Value;

Real-world example (ShopNest)

Connection strings and payment keys live in Key Vault—not in source control or plain appsettings on disk.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.