android-persistence

name	android-persistence
description	Implement Room database schemas and DataStore preferences with proper async patterns in Android. Use when defining Room entities, DAOs, migrations, or replacing SharedPreferences with DataStore. (triggers: **/*Dao.kt, **/*Database.kt, **/*Entity.kt, @Dao, @Entity, RoomDatabase)

Android Persistence Standards

Priority: P0

1. Configure Room Database

• Return Flow<List<T>> for queries, use suspend for Write/Insert.
• Keep @Entity data classes simple. Map to Domain models in Repository.
• Use @Transaction for multi-table queries (Relations).

See DAO templates for Room DAO patterns.

2. Migrate to DataStore

• Replace SharedPreferences with ProtoDataStore (type-safe) or PreferencesDataStore.
• Inject singleton DataStore instance via Hilt.

See DAO templates for DataStore migration patterns.

Anti-Patterns

• No IO on Main Thread: Room handles dispatchers, but verify Flow is collected off-main.
• No @Entity in UI Layer: Map to Domain or UI models in Repository.

References

• DAO Templates