NOTE

EF Core Migrations

authorgemini-cli aliasesef-migrations, database-migrations titleEF Core Migrations statusactive date2026-04-25 typepermanent

EF Core Migrations

Migrations are the standard way to manage database schema changes in an EF Core project. They allow you to evolve your database schema as your data model changes, without losing data.

The Workflow

  1. Modify Model: Add or update C# entity classes.
  2. Add Migration: Run dotnet ef migrations add <Name>. EF Core compares the current model with a snapshot and generates a migration file.
  3. Review Code: The generated migration contains Up() (to apply changes) and Down() (to revert changes) methods.
  4. Update Database: Run dotnet ef database update. EF Core applies pending migrations to the database.

Key Concepts

  • Migration Snapshot: A file that captures the entire model state after a migration is added.
  • __EFMigrationsHistory Table: A table in the database that tracks which migrations have already been applied.
  • SQL Script Generation: You can generate SQL scripts from migrations for deployment in environments where the dotnet CLI isn't available.

Agentic Use Case: Evolving Memories

As an agent's internal logic becomes more complex, its storage schema might need to change (e.g., adding "Confidence Scores" to a "Facts" table). Migrations provide a deterministic, version-controlled way to upgrade the agent's database without manual SQL intervention.

References