App Services Databases - MSDN Documentation

Integrating Databases with Azure App Services

Azure App Services provides robust capabilities for connecting your web applications to various database services. This section details common integration patterns, best practices, and supported database technologies.

Supported Database Services

Azure App Services can seamlessly connect to a wide range of managed database services, including:

Azure SQL Database: A fully managed relational database service that provides the Microsoft SQL Server engine in the cloud.
Azure Database for MySQL: A fully managed relational database service built on the MySQL community edition.
Azure Database for PostgreSQL: A fully managed relational database service built on the PostgreSQL community edition.
Azure Cosmos DB: A globally distributed, multi-model database service that supports various APIs, including SQL (document), MongoDB, Cassandra, Gremlin, and Table.
External Databases: You can also connect to databases hosted outside of Azure, provided they are accessible over the network.

Connection Methods

There are several ways to establish connections between your App Service and your database:

Connection Strings: The most common method. Connection strings are stored securely in your App Service's application settings and can be accessed by your application code. Azure automatically populates common database connection strings for services hosted within the same subscription.
Environment Variables: Connection information can also be exposed as environment variables, offering an alternative to connection strings.
Key Vault Integration: For enhanced security, store database credentials and connection strings in Azure Key Vault and reference them from your App Service's application settings.

Best Practices for Database Integration

To ensure a secure, performant, and reliable application, consider these best practices:

Secure Credentials

Never hardcode database credentials in your application code. Utilize App Service application settings or Azure Key Vault for secure credential management.

Network Security

Configure firewall rules for your database to only allow connections from your App Service's IP address or VNet integration endpoints. Use Private Endpoints for maximum security.

Connection Pooling

Implement connection pooling in your application to reuse database connections, significantly improving performance and reducing overhead.

Connection String Management

Leverage Azure's built-in connection string management. For custom or external databases, define them manually in application settings.

Read Replicas and High Availability

For production workloads, consider setting up read replicas for offloading read traffic and configuring high availability for your database to ensure business continuity.

Example: Connecting to Azure SQL Database

Here's a conceptual example using C# and Entity Framework Core. Your application settings in Azure App Services would contain an entry like:

ConnectionStrings:DefaultConnection = Server=tcp:your_server.database.windows.net,1433;Initial Catalog=your_db;Persist Security Info=False;User ID=your_user;Password=your_password;MultipleActiveResultSets=False;Encrypt=True;TrustServerCertificate=False;Connection Timeout=30;

And in your application's configuration (e.g., Program.cs or Startup.cs):

builder.Services.AddDbContext(options =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));

Important: When deploying to Azure App Services, use the connection strings provided directly in the "Connection strings" section of your App Service configuration blade. Azure automatically injects these values into the ConnectionStrings collection.

Next Steps

Explore the documentation for specific database services to learn about advanced configuration, performance tuning, and security features.