servicestack-schema-migrations

name	servicestack-schema-migrations
description	Manages schema evolution using OrmLite migrations and deployment-safe patterns.

ServiceStack Schema Migrations

ServiceStack recommended approach for database schema changes is code-first migrations.

Basic Migration Structure

• Create classes that inherit from MigrationBase.
• Implement the Up and Down methods.
• Use Db.CreateTable<T>, Db.DropTable<T>, Db.AddColumn<T>, etc.

public class Migration1000 : MigrationBase
{
    public override void Up()
    {
        Db.CreateTable<Customer>();
    }

    public override void Down()
    {
        Db.DropTable<Customer>();
    }
}

Running Migrations

• Migrations can be run from the command line using dotnet run -- AppTasks=migrate.
• They are typically stored in a Migrations folder in the AppHost project.

Conventions

• Naming: Use a sequential or timestamp-based naming convention (e.g., Migration1000, Migration20231027_Initial).
• Declarative: Use declarative migrations (Db.CreateTable<T>) where possible to keep POCOs as the source of truth.
• Imperative: Use Db.ExecuteSql("...") if you need complex transformations or custom SQL that OrmLite doesn't support directly.

Best Practices

• Never Update Old Migrations: Once a migration is committed and shared, never change it. Create a new one.
• Test Rollbacks: Always implement and test the Down method.
• Idempotency: Ensure your migrations are safe to run even if some parts of the schema already exist (though ServiceStack's migration runner handles the tracking).
• Deployment: Integrate migration execution into your CI/CD pipeline or application startup (with care).