Room Database Migration: Auto and Manual Migration Strategies

As apps evolve, database schemas change. Learn Room migration, version management, and automated vs manual approaches. Define Database Version import androidx.room.Database import androidx.room.RoomDatabase @Database ( entities = [ User :: class ], version = 2 // Increment on schema change ) abstract class AppDatabase : RoomDatabase () { abstract fun userDao (): UserDao } Manual Migration with SQL val migration1to2 = object : Migration ( 1 , 2 ) { override fun migrate ( db : SupportSQLiteDatabase ) { // Add new column db . execSQL ( "ALTER TABLE users ADD COLUMN email TEXT" ) } } val db = Room . databaseBuilder ( context , AppDatabase :: class . java , "app.db" ) . addMigrations ( migration1to2 ) . build () Auto Migration (Room 2.4+) @Database ( entities = [ User :: class ], version = 3 , autoMigrations = [ AutoMigration ( from = 1 , to = 2 ), AutoMigration ( from = 2 , to = 3 ) ] ) abstract class AppDatabase : RoomDatabase () Modify Entity // Version 1 @Entity ( tableName = "users" )