EF Core Migrations

Overview

Entity Framework Core migrations allow you to evolve your database schema alongside your code. This example shows how to run migrations as part of your ANDO build pipeline.

Basic Migration

Apply pending migrations to a database:

var project = Dotnet.Project("./src/WebApp/WebApp.csproj");

// Build the project first (required for EF tools)
Dotnet.Restore(project);
Dotnet.Build(project);

// Reference the DbContext
var dbContext = Ef.DbContextFrom(project, "AppDbContext");

// Apply migrations
Ef.DatabaseUpdate(dbContext, Env("CONNECTION_STRING"));

Migration with Bicep Deployment

Get the connection string from a Bicep deployment output:

var deploy = DefineProfile("deploy");

var project = Dotnet.Project("./src/WebApp/WebApp.csproj");

Dotnet.Restore(project);
Dotnet.Build(project);

if (deploy)
{
    Azure.EnsureAuthenticated();

    // Deploy infrastructure
    var deployment = Bicep.DeployToResourceGroup("my-rg", "./infra/main.bicep");

    // Get connection string from deployment output
    var dbContext = Ef.DbContextFrom(project, "AppDbContext");
    Ef.DatabaseUpdate(dbContext, deployment.Output("sqlConnectionString"));

    Log.Info("Migrations applied successfully");
}

Generate SQL Script

For production deployments, generate a SQL script instead of running migrations directly:

var project = Dotnet.Project("./src/WebApp/WebApp.csproj");

Dotnet.Restore(project);
Dotnet.Build(project);

var dbContext = Ef.DbContextFrom(project, "AppDbContext");

// Generate idempotent migration script
Ef.Script(dbContext, Root / "migrations.sql");

// Copy script to host for manual review/execution
Ando.CopyArtifactsToHost("migrations.sql", "./artifacts/migrations.sql");

Log.Info("Migration script generated at ./artifacts/migrations.sql");

Multiple DbContexts

Handle multiple database contexts in the same project:

var project = Dotnet.Project("./src/WebApp/WebApp.csproj");

Dotnet.Restore(project);
Dotnet.Build(project);

// Reference multiple contexts
var appContext = Ef.DbContextFrom(project, "AppDbContext");
var auditContext = Ef.DbContextFrom(project, "AuditDbContext");

// Apply migrations to each
Ef.DatabaseUpdate(appContext, Env("APP_CONNECTION_STRING"));
Ef.DatabaseUpdate(auditContext, Env("AUDIT_CONNECTION_STRING"));

Log.Info("All database migrations applied");

Conditional Migrations

Only run migrations in specific profiles:

var deploy = DefineProfile("deploy");
var migrateOnly = DefineProfile("migrate");

var project = Dotnet.Project("./src/WebApp/WebApp.csproj");

Dotnet.Restore(project);
Dotnet.Build(project);

// Migrations run in both deploy and migrate profiles
if (deploy || migrateOnly)
{
    var dbContext = Ef.DbContextFrom(project, "AppDbContext");
    Ef.DatabaseUpdate(dbContext, Env("CONNECTION_STRING"));
    Log.Info("Migrations applied");
}

// Full deployment only in deploy profile
if (deploy)
{
    Dotnet.Publish(project, o => o.Output(Root / "publish"));
    Azure.EnsureAuthenticated();
    AppService.DeployZip("my-webapp", Root / "publish");
}

Usage:

# Run migrations only
ando -p migrate

# Full deployment with migrations
ando -p deploy

Full Example: Web App with Migrations

Complete deployment including database migrations:

var deploy = DefineProfile("deploy");

var webProject = Dotnet.Project("./src/WebApp/WebApp.csproj");
var testProject = Dotnet.Project("./tests/WebApp.Tests/WebApp.Tests.csproj");

// Build and test
Dotnet.SdkInstall();
Dotnet.Restore(webProject);
Dotnet.Build(webProject);
Dotnet.Test(testProject);

if (deploy)
{
    Azure.EnsureAuthenticated();

    // 1. Run migrations BEFORE deployment
    var dbContext = Ef.DbContextFrom(webProject, "AppDbContext");
    Ef.DatabaseUpdate(dbContext, Env("CONNECTION_STRING"));
    Log.Info("Database migrations applied");

    // 2. Publish application
    Dotnet.Publish(webProject, o => o
        .WithConfiguration(Configuration.Release)
        .Output(Root / "publish"));

    // 3. Deploy with zero-downtime swap
    AppService.DeployWithSwap("my-webapp", Root / "publish", "staging");

    Log.Info("Deployment complete!");
}

Key Operations

Operation	Purpose
Ef.DbContextFrom()	Reference a DbContext in a project
Ef.DatabaseUpdate()	Apply pending migrations
Ef.Script()	Generate SQL migration script

Tips

Run migrations before deployment - Ensures the database schema is ready before new code starts
Use scripts for production - Generate and review SQL scripts instead of running migrations directly
Test with a staging database - Run migrations against a staging database first
Handle rollbacks - Keep migration scripts to enable manual rollbacks if needed