Connect to Azure SQL with EF Core

This page describes how C# consuming apps connect to an Azure SQL database resource that’s already modeled in your AppHost. For the AppHost API surface — adding an Azure SQL server, databases, running as a container, connecting to existing servers, and more — see Set up Azure SQL in the AppHost.

Note

The EF Core client integration (Aspire.Microsoft.EntityFrameworkCore.SqlServer) is a C#-only integration. If your consuming app is written in TypeScript, Python, Go, or another language, read the injected connection environment variables directly. For per-language connection examples, see Connect to Azure SQL Database.

When you reference an Azure SQL database resource from your AppHost, Aspire injects connection information into the consuming app as environment variables. In C#, the recommended approach is the Aspire EF Core client integration — it registers a DbContext through dependency injection and adds health checks and telemetry automatically.

Connection properties

Aspire exposes each property as an environment variable named [RESOURCE]_[PROPERTY]. For instance, the Uri property of a resource called database becomes DATABASE_URI.

Azure SQL server resource

The Azure SQL server resource exposes the following connection properties:

Property Name	Description
Host	The hostname or IP address of the Azure SQL Server
Port	The port number the SQL Server is listening on
Username	The username for authentication
Password	The password for authentication
Uri	The connection URI in mssql:// format, with the format mssql://{Username}:{Password}@{Host}:{Port}
JdbcConnectionString	JDBC-format connection string, with the format jdbc:sqlserver://{Host}:{Port};trustServerCertificate=true. User and password credentials are provided as separate Username and Password properties.

Example connection strings:

Uri: mssql://sa:p%40ssw0rd1@myserver.database.windows.net:1433
JdbcConnectionString: jdbc:sqlserver://myserver.database.windows.net:1433;trustServerCertificate=true

Azure SQL database resource

The Azure SQL database resource inherits all properties from its parent AzureSqlServerResource and adds:

Property Name	Description
Uri	The connection URI in mssql:// format, with the format mssql://{Username}:{Password}@{Host}:{Port}/{DatabaseName}
JdbcConnectionString	JDBC connection string with database name, with the format jdbc:sqlserver://{Host}:{Port};trustServerCertificate=true;databaseName={DatabaseName}. User and password credentials are provided as separate Username and Password properties.
DatabaseName	The name of the database

Example connection strings:

Uri: mssql://sa:p%40ssw0rd1@myserver.database.windows.net:1433/catalog
JdbcConnectionString: jdbc:sqlserver://myserver.database.windows.net:1433;trustServerCertificate=true;databaseName=catalog

Connect from your app

Add the Aspire EF Core Azure SQL client integration to your C# consuming app to register a DbContext for Azure SQL with automatic health checks and telemetry.

C#

Install the EF Core client integration

Install the 📦 Aspire.Microsoft.EntityFrameworkCore.SqlServer NuGet package in the client-consuming project:

.NET CLI

.NET CLI — Add Aspire.Microsoft.EntityFrameworkCore.SqlServer package

dotnet add package Aspire.Microsoft.EntityFrameworkCore.SqlServer

Program.cs (C# file-based app)

Program.cs

#:package Aspire.Microsoft.EntityFrameworkCore.SqlServer@*

PackageReference (*.csproj)

XML — Add Aspire.Microsoft.EntityFrameworkCore.SqlServer package reference

<PackageReference Include="Aspire.Microsoft.EntityFrameworkCore.SqlServer" Version="*" />

Add SQL Server database context

In Program.cs, call AddSqlServerDbContext on your IHostApplicationBuilder to register a Microsoft.EntityFrameworkCore.DbContext for use via the dependency injection container. The method takes a connection name parameter:

C# — Program.cs

builder.AddSqlServerDbContext<ExampleDbContext>(
    connectionName: "database");

Note

To use this code, you must create a DbContext class called ExampleDbContext in your project. This class defines your database schema using EF Core. For more information on creating and configuring a DbContext, see DbContext Lifetime, Configuration, and Initialization in the EF Core documentation.

Astuce

The connectionName must match the Azure SQL database resource name from the AppHost. For example, when you call AddDatabase("database"), use "database" as the connection name here.

Resolve ExampleDbContext through dependency injection:

C# — ExampleService.cs

public class ExampleService(ExampleDbContext context)
{
    // Use context...
}

For more information on dependency injection, see .NET dependency injection.

Enrich a SQL Server database context

You may prefer to use the standard Entity Framework method to obtain a database context and add it to the dependency injection container:

C# — Program.cs

builder.Services.AddDbContext<ExampleDbContext>(options =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("database")
        ?? throw new InvalidOperationException("Connection string 'database' not found.")));

Note

The connection string name that you pass to GetConnectionString must match the name used when adding the SQL server resource in the AppHost project.

You have more flexibility when you create the database context in this way, for example:

• You can reuse existing configuration code for the database context without rewriting it for Aspire.
• You can use Entity Framework Core interceptors to modify database operations.
• You can choose not to use Entity Framework Core context pooling, which may perform better in some circumstances.

If you use this method, enhance the database context with Aspire-style retries, health checks, logging, and telemetry by calling EnrichSqlServerDbContext:

C# — Program.cs

builder.EnrichSqlServerDbContext<ExampleDbContext>(
    configureSettings: settings =>
    {
        settings.DisableRetry = false;
        settings.CommandTimeout = 30; // seconds
    });

The settings parameter is an instance of the MicrosoftEntityFrameworkCoreSqlServerSettings class.

Configuration

The Aspire SQL Server Entity Framework Core integration provides multiple configuration approaches to meet the requirements and conventions of your project.

Use connection string

When using a connection string from the ConnectionStrings configuration section, provide the name of the connection string when calling AddSqlServerDbContext<TContext>():

C# — Program.cs

builder.AddSqlServerDbContext<ExampleDbContext>("sql");

The connection string is retrieved from the ConnectionStrings configuration section:

JSON — appsettings.json

{
  "ConnectionStrings": {
    "sql": "Data Source=myserver;Initial Catalog=master"
  }
}

The EnrichSqlServerDbContext won’t make use of the ConnectionStrings configuration section since it expects a DbContext to be registered at the point it’s called.

For more information, see ConnectionString.

Use configuration providers

The Aspire SQL Server Entity Framework Core integration supports Microsoft.Extensions.Configuration. It loads MicrosoftEntityFrameworkCoreSqlServerSettings from appsettings.json (or any other configuration source) by using the Aspire:Microsoft:EntityFrameworkCore:SqlServer key:

JSON — appsettings.json

{
  "Aspire": {
    "Microsoft": {
      "EntityFrameworkCore": {
        "SqlServer": {
          "ConnectionString": "YOUR_CONNECTIONSTRING",
          "DbContextPooling": true,
          "DisableHealthChecks": true,
          "DisableTracing": true,
          "DisableMetrics": false
        }
      }
    }
  }
}

Use inline configurations

Pass an Action<MicrosoftEntityFrameworkCoreSqlServerSettings> delegate to set up options inline, for example to disable metrics:

C# — Program.cs

builder.AddSqlServerDbContext<YourDbContext>(
    "sql",
    static settings =>
        settings.DisableMetrics = true);

Configure multiple DbContext connections

If you want to register more than one DbContext with different configuration, use the $"Aspire.Microsoft.EntityFrameworkCore.SqlServer:{typeof(TContext).Name}" configuration section name:

JSON — appsettings.json

{
  "Aspire": {
    "Microsoft": {
      "EntityFrameworkCore": {
        "SqlServer": {
          "ConnectionString": "YOUR_CONNECTIONSTRING",
          "DbContextPooling": true,
          "DisableHealthChecks": true,
          "DisableTracing": true,
          "DisableMetrics": false,
          "AnotherDbContext": {
            "ConnectionString": "AnotherDbContext_CONNECTIONSTRING",
            "DisableTracing": false
          }
        }
      }
    }
  }
}

Then calling AddSqlServerDbContext with the AnotherDbContext type parameter loads the settings from Aspire:Microsoft:EntityFrameworkCore:SqlServer:AnotherDbContext:

C# — Program.cs

builder.AddSqlServerDbContext<AnotherDbContext>("another-sql");

Configuration options

Here are the configurable options with corresponding default values:

Name	Description
ConnectionString	The connection string of the SQL Server database to connect to.
DbContextPooling	A boolean value that indicates whether the db context will be pooled or explicitly created every time it’s requested
MaxRetryCount	The maximum number of retry attempts. Default value is 6, set it to 0 to disable the retry mechanism.
DisableHealthChecks	A boolean value that indicates whether the database health check is disabled or not.
DisableTracing	A boolean value that indicates whether the OpenTelemetry tracing is disabled or not.
DisableMetrics	A boolean value that indicates whether the OpenTelemetry metrics are disabled or not.
Timeout	The time in seconds to wait for the command to execute.

Client integration health checks

Aspire client integrations enable health checks by default. The SQL Server EF Core client integration adds:

• The DbContextHealthCheck, which calls EF Core’s CanConnectAsync method. The name of the health check is the name of the TContext type.
• Integration with the /health HTTP endpoint, which specifies all registered health checks must pass for the app to be considered ready to accept traffic.

Observability and telemetry

Aspire integrations automatically set up Logging, Tracing, and Metrics configurations.

Logging

The Aspire SQL Server Entity Framework Core integration uses the following log categories:

• Microsoft.EntityFrameworkCore.ChangeTracking
• Microsoft.EntityFrameworkCore.Database.Command
• Microsoft.EntityFrameworkCore.Database.Connection
• Microsoft.EntityFrameworkCore.Database.Transaction
• Microsoft.EntityFrameworkCore.Infrastructure
• Microsoft.EntityFrameworkCore.Migrations
• Microsoft.EntityFrameworkCore.Model
• Microsoft.EntityFrameworkCore.Model.Validation
• Microsoft.EntityFrameworkCore.Query
• Microsoft.EntityFrameworkCore.Update

Tracing

The Aspire SQL Server Entity Framework Core integration emits the following tracing activities using OpenTelemetry:

• OpenTelemetry.Instrumentation.EntityFrameworkCore

Metrics

The Aspire SQL Server Entity Framework Core integration emits the following metrics using OpenTelemetry:

• Microsoft.EntityFrameworkCore:
  • ec_Microsoft_EntityFrameworkCore_active_db_contexts
  • ec_Microsoft_EntityFrameworkCore_total_queries
  • ec_Microsoft_EntityFrameworkCore_queries_per_second
  • ec_Microsoft_EntityFrameworkCore_total_save_changes
  • ec_Microsoft_EntityFrameworkCore_save_changes_per_second
  • ec_Microsoft_EntityFrameworkCore_compiled_query_cache_hit_rate
  • ec_Microsoft_Entity_total_execution_strategy_operation_failures
  • ec_Microsoft_E_execution_strategy_operation_failures_per_second
  • ec_Microsoft_EntityFramew_total_optimistic_concurrency_failures
  • ec_Microsoft_EntityF_optimistic_concurrency_failures_per_second