Database migrations

The rule

The schema comes only from migrations in src/Infrastructure/Databases/MovieReviews/Migrations. The app applies pending migrations at startup in InitialiseInfrastructure(), and the tests build their databases from the same migrations, so a model change without a migration fails the tests. MovieReviewsDbContextFactory lets the EF Core tools create the context at design time.

Steps

1. Change the database model in Models/ and its configuration in Configuration/. Relationships, keys, indexes and collations are configured with the fluent API in an EntityConfiguration<T> subclass. Text people search or sort by uses UseCollation(Collations.NoCase), and columns we sort or filter by get a HasIndex.
2. Install the tool once: dotnet tool install --global dotnet-ef.

3. Add the migration from the repository root:

   dotnet ef migrations add <Name> \
     --project ./src/Infrastructure \
     --output-dir Databases/MovieReviews/Migrations \
     --namespace CleanModelContextProtocol.Infrastructure.Databases.MovieReviews.Migrations

4. Check where the files landed. If MovieReviewsDbContextModelSnapshot.cs was written somewhere else or in another namespace, move it into Migrations/ and fix its namespace.

5. Strip the byte order mark the tool adds, so dotnet format and the diff stay clean, and make sure the migration file starts with // <auto-generated /> so the analysers skip it. The tool adds that line to the .Designer.cs file but not always to the migration itself:

   sed -i '1s/^\xEF\xBB\xBF//' src/Infrastructure/Databases/MovieReviews/Migrations/*.cs

6. Rename both files and the [Migration] attribute to <yyyyMMdd>000000_<Name>, so the id is the day it was written and not the second you ran the tool.
7. Name the migration for what it does (AddReviewComment), in PascalCase.
8. Update MovieReviewsDbContextExtensions.AddData and the test data if the new column needs a value (sample-data).
9. Check nothing is left over with dotnet ef migrations has-pending-model-changes --project ./src/Infrastructure, then run every test project. Migrations are excluded from coverage.

Don't

• Edit a migration that has already been released. Add a new one.
• Call EnsureCreated() anywhere. It skips migrations.
• Use ValueGeneratedOnAdd() on DateCreated or DateModified. SQLite then tries to insert NULL into a NOT NULL column; the repository sets both.
• Add data annotations like [Required] or [MaxLength] to models. Configure in Configuration/.

Check

dotnet build
dotnet test
dotnet format --verify-no-changes