room数据库升级报错

room数据库升级报错

网上说是有重复字段 但我就是这个版本升级的时候 添加了一个time字段，希望帮忙看看


@Database(version = 2, entities = [LoversBean::class])
abstract class AppDatabase : RoomDatabase() {
    abstract fun userDao(): LoversDao
    companion object {
        private var instance: AppDatabase? = null
        @Synchronized
        fun getDatabase(context: Context): AppDatabase {
            instance?.let {
                return it
            }

            return Room.databaseBuilder(context.applicationContext,
                AppDatabase::class.java, "app_database")
                .addMigrations(MIGRATION_1_2)
                .build().apply {
                    instance = this
                }
        }
        private val MIGRATION_1_2 =object :Migration(1,2){
            override fun migrate(database: SupportSQLiteDatabase) {
                database.execSQL("alter table LoversBean add column time text")
            }
        }
    }
}


@Entity
data class LoversBean(
    val content: String,
    val type: Int = CONTENT_LEFT,
    val time :String ?=null){
    @PrimaryKey(autoGenerate = true)
    var id: Long = 0
}
运行结果及报错内容

duplicate column name: time (code 1 SQLITE_ERROR): , while compiling: alter table LoversBean add column time text

我的解答思路和尝试过的方法

网上说是有重复字段 我就是这个版本升级的时候 添加了一个time字段，希望帮忙看看