Practical room migrations

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" summary

Room’s migration flow is practical and concrete: Auto Migrations generate implementations if schemas are exported, and ambiguous renames use a Migration Spec with annotations like RenameTable/RenameColumn/DeleteColumn/DeleteTable and a PostMigrate hook for data conversion. Manual migrations run before an auto migration to sanitize rows (example: remove invalid child foreign-key refs) so adding constraints succeeds. Tests use the Migration Test Helper and runMigrationsAndValidate to create old-version DBs, migrate, validate schema, and assert migrated data.

AI-written summary · about

" chapters (9)

1. 0:00Intro
2. 0:22Not every database needs to be migrated
3. 1:07Auto migrations
4. 2:22Postmigrate
5. 3:00Manual migration
6. 3:27Manual migration example
7. 3:54Column info migration
8. 4:18Migration box
9. 4:48Testing migrations

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