Room Database Offline-First Architecture

In an offline-first design, the database is the observable source of truth. Network responses update Room, and the UI observes Room through Flow. This avoids competing local and remote states.

Practical guidance

• Render DAO flows instead of returning the latest network body directly.
• Wrap related writes in transactions.
• Track sync metadata such as server version or updatedAt.
• Schedule durable sync with WorkManager under appropriate constraints.

Working example

@Dao
interface ArticleDao {
    @Query("SELECT * FROM articles ORDER BY updatedAt DESC")
    fun observeAll(): Flow<List<ArticleEntity>>

    @Upsert
    suspend fun upsertAll(items: List<ArticleEntity>)
}

suspend fun refresh() { dao.upsertAll(api.articles().map { it.toEntity() }) }

Common mistakes

• Deleting all rows before inserting creates empty-state flicker unless transactional.
• Last-write-wins is a policy, not a universal conflict solution.
• Database entities should not leak into Compose screens.

Key takeaway

Make synchronization an explicit data-layer responsibility. The UI should observe one source and remain usable when the network disappears.

Related tutorials

• MVVM Architecture in Android