Android Room Database Migration (Upgrade Version) - Kotlin

@Entity(tableName = "pin")class Pin (        // old fields        @PrimaryKey        @ColumnInfo(name = "id") var id: String = "",        @ColumnInfo(name = "name") var name: String = "",        @ColumnInfo(name = "lat") var lat: Double? = null,        @ColumnInfo(name = "lng") var lat: Double? = null,                // new field        @ColumnInfo(name = "is_location_accurate") var isLocationAccurate: Boolean = false        ) {        }

val MIGRATION_1_2: Migration = object : Migration(1, 2) {    override fun migrate(database: SupportSQLiteDatabase) {        // https://developer.android.com/reference/android/arch/persistence/room/ColumnInfo        /*        database.execSQL("ALTER TABLE pin "                + " ADD COLUMN is_location_accurate INTEGER")         */        database.execSQL("ALTER TABLE pin "                + " ADD COLUMN is_location_accurate INTEGER NOT NULL DEFAULT 0")        database.execSQL("UPDATE pin "                + " SET is_location_accurate = 0 WHERE lat IS NULL")        database.execSQL("UPDATE pin "                + " SET is_location_accurate = 1 WHERE lat IS NOT NULL")    }}

val database = Room.databaseBuilder(app, AppDatabase::class.java, "PixPin.db")        // addMigrations(MIGRATION_1_2, MIGRATION_2_3)        .addMigrations(MIGRATION_1_2)        .build()

@Database(entities = [(Pin::class), (PinGroup::class), (Image::class), Test::class], version = 2, exportSchema = false)@TypeConverters(RoomConverters::class)abstract class AppDatabase : RoomDatabase() {    abstract fun pinDao(): PinDao    abstract fun imageDao(): ImageDao}