Room database bug report Created Tuesday 01 April ...

# android

[Vinay Sajip]

Room database bug report
Created Tuesday 01 April 2025

I'm hitting a problem using Room with a pre-packaged SQLite database. Here is the schema of the single table I'm trying to work with, copy-pasted from the SQLIte3 CLI:

SQLite version 3.37.2 2022-01-06 13:25:41
Enter ".help" for usage hints.
sqlite> .schema product
CREATE TABLE IF NOT EXISTS "product" (
"id" INTEGER NOT NULL,
"slug" TEXT NOT NULL UNIQUE,
"label" TEXT NOT NULL UNIQUE,
"price" NUMERIC NOT NULL,
PRIMARY KEY("id" AUTOINCREMENT)
);

Here are my entity definition corresponding to this table, the DAO to access it, the ViewModel and the database setup:

@Entity(tableName = "product")
data class Product(
@PrimaryKey(autoGenerate = true)
val id: Int,
val slug: String,
val label: String,
val price: Double,
@Ignore val quantity: Int,
) {
constructor(id: Int, slug: String, label: String, price: Double) : this(id, slug, label, price, 0)
}

@Dao
interface ProductData {
@Query("SELECT * FROM product")
fun getAllProducts(): List<Product>
}

class ProductViewModel(private val data: ProductData) : ViewModel() {
val products = data.getAllProducts()
}

@Database(
version = 1,
entities = [Product::class],
exportSchema = false,
)
abstract class AppDatabase : RoomDatabase() {

abstract val product: ProductData

companion object {
@Volatile
private var INSTANCE: AppDatabase? = null

fun getInstance(context: Context): AppDatabase {
synchronized(this) {
return INSTANCE ?: Room.databaseBuilder(
context.applicationContext,
AppDatabase::class.java,
"viscount.db"
)
.createFromAsset("data/viscount.db")
.build().also { INSTANCE = it }
}
}
}
}

here is how I set it up in my main activity:

class MainActivity : ComponentActivity() {

private val db by lazy { AppDatabase.getInstance(this) }

private val viewModel by viewModels<ProductViewModel>(
factoryProducer = {
object : ViewModelProvider.Factory {
override fun <T : ViewModel> create(modelClass: Class<T>): T {
return ProductViewModel(db.product) as T
}
}
}
)

// other code omitted for brevity
}


The error occurs on the line return ProductViewModel(db.product) as T and here is a partial log from LogCat:

java.lang.IllegalStateException: Pre-packaged database has an invalid schema: product(com.red_dove.viscount.Product).
Expected:
TableInfo{name='product', columns={id=Column{name='id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='undefined'}, label=Column{name='label', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='undefined'}, slug=Column{name='slug', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='undefined'}, price=Column{name='price', type='REAL', affinity='4', notNull=true, primaryKeyPosition=0, defaultValue='undefined'}}, foreignKeys=[], indices=[]}
Found:
TableInfo{name='product', columns={id=Column{name='id', type='INTEGER', affinity='3', notNull=false, primaryKeyPosition=1, defaultValue='undefined'}, slug=Column{name='slug', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='undefined'}, label=Column{name='label', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='undefined'}, price=Column{name='price', type='NUMERIC', affinity='1', notNull=true, primaryKeyPosition=0, defaultValue='undefined'}}, foreignKeys=[], indices=[]}
at androidx.room.RoomOpenHelper.onCreate(RoomOpenHelper.kt:73)
at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.onCreate(FrameworkSQLiteOpenHelper.kt:244)
at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:432)
at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:336)
at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.getWritableOrReadableDatabase(FrameworkSQLiteOpenHelper.kt:232)
at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.innerGetDatabase(FrameworkSQLiteOpenHelper.kt:190)
at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.getSupportDatabase(FrameworkSQLiteOpenHelper.kt:151)
at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper.getWritableDatabase(FrameworkSQLiteOpenHelper.kt:104)
at androidx.room.SQLiteCopyOpenHelper.getWritableDatabase(SQLiteCopyOpenHelper.kt:71)
at androidx.room.RoomDatabase.inTransaction(RoomDatabase.kt:632)
at androidx.room.RoomDatabase.assertNotSuspendingTransaction(RoomDatabase.kt:451)
at com.red_dove.viscount.ProductData_Impl.getAllProducts(ProductData_Impl.java:31)
at com.red_dove.viscount.ProductViewModel.<init>(Data.kt:33)
at com.red_dove.viscount.MainActivity$viewModel$2$1.create(MainActivity.kt:27)

The only relevant difference I can see in the "expected" vs "found" lines is that we're expecting

id=Column{name='id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='undefined'}

but finding

id=Column{name='id', type='INTEGER', affinity='3', notNull=false, primaryKeyPosition=1, defaultValue='undefined'}

Can anyone explain why it finds notNull=false when by the table definiion clearly it should be marked as notNull=true, the expected value?

[Seri]

Are you exported your Room schema as a JSON? What does your generated schema's CREATE TABLE IF NOT EXISTS "product" string look like?

[Chrimaeon]

1. Please post long code code snippets in the thread.
2. this is a slack workspace for the Kotlin programming language.
3. Your Android/Google question is off topic here.

[Chrimaeon]

Image from iOS.jpg

[Seri]

not even going to redirect them to #C7KS458SJ? 🙁

[Chrimaeon]

Not much going on there so I doubt they’ll get answers there.

[Vinay Sajip]

@Chrimaeon Sorry, I didn't realize it would be OT here ... @Seri I didn't export the schema. Not sure where I'd get the CREATE TABLE from the generated schema. OK, I'll hop over to Discord, thanks for your time.

[walid]

send your architcure for project if use remote data source or local data you or both ,you should create repository and inmplemnete it layer of data use a clean architcure i didn't see the reposorty dependency in view model used in domain layer ,the reposotry and suspended fun for http call and i advise you to use dagger hilt

[Chrimaeon]

What does your suggestion have to do with a failing room schema validation? 🤣

[Seri]

Go ahead and export your schema, then search it for "createSql" to find the generated query

[Baghaii]

It looks like where you are creating the table, the price should be REAL and not NUMERIC, I think.