| name | migrations |
| description | Implementation details for EF Core migrations. Use when changing MigrationsSqlGenerator, model diffing, migration operations, HistoryRepository, the Migrator or related classes. |
| user-invocable | false |
Migrations
Pipeline
Add migration: MigrationsScaffolder.ScaffoldMigration() → MigrationsModelDiffer.GetDifferences() → list of MigrationOperation → CSharpMigrationsGenerator and CSharpSnapshotGenerator produce Up/Down/Snapshot code
Apply migration: Migrator.MigrateAsync() → reads __EFMigrationsHistory → per pending: MigrationsSqlGenerator.Generate(operations) → MigrationCommandExecutor executes
Model Snapshot
- Model snapshots use
typeof(Dictionary<string, object>) (property bag format), not the actual CLR type. When examining the ClrType in a snapshot, don't assume it matches the real entity type.
SnapshotModelProcessor.Process() is used at design-time to fixup older model snapshots for backward compatibility.
Testing
Migration operation tests: test/EFCore.Relational.Tests/Migrations/. Functional tests: test/EFCore.{Provider}.FunctionalTests/Migrations/. Model differ tests: test/EFCore.Relational.Tests/Migrations/Internal/MigrationsModelDifferTest*.cs.
