Compose Room Database Quiz Pt 2

Welcome to the Room Database Quiz! This quiz will test your knowledge of implementing SQLite-based database storage using the Room persistence library in Android applications. The questions cover various aspects, including setting up a Room database, working with entities, DAOs, repositories, and integrating these with a ViewModel and Jetpack Compose UI. Whether you’re revisiting concepts or testing your understanding, this quiz is designed to help reinforce your learning and ensure you’re ready to build robust data-driven Android apps.

What does the 'fallbackToDestructiveMigration()' method do in Room?

Backs up the database before migration.

Prevents data loss during migrations.

Automatically updates the database schema without data loss.

Deletes and recreates the database if a migration is not found.

None

What is the role of a Repository class when working with Room databases?

To create UI components.

To manage API calls.

To provide direct access to the database.

To abstract data operations and interact with the DAO.

None

Which component is typically responsible for managing the UI state in the Room-based project?

Repository

Database

ViewModel

DAO

None

Which library is required for handling asynchronous Room database queries?

Glide

Retrofit

Coroutines

Dagger

None

How is a Room database instance created in the RoomDemo project?

By creating a custom SQL engine.

By writing raw SQL queries.

By extending the RoomDatabase class and using ‘Room.databaseBuilder’.

By directly instantiating the RoomDatabase class.

None

Which function is used to prevent blocking the main thread during database operations?

AsyncTask()

Thread.sleep()

runOnUiThread()

launch() with Dispatchers.IO

None

Which annotation is used to define a class as an entity in Room?

@Dao

@Entity

@Table

@Database

None

What is the purpose of using 'MutableLiveData' in a repository?

To create a backup of database data.

To manage UI theme changes.

To store search results for observed updates.

To define database table schemas.

None

Why is it important to avoid performing database operations on the main thread?

To ensure the app’s UI remains responsive.

To improve network performance.

To enable debugging features.

To reduce battery consumption.

None

10.

How can changes to database records be automatically reflected in the UI?

By directly accessing the database in the UI.

By storing data in SharedPreferences.

By setting up manual refresh methods in the DAO.

By using ‘LiveData’ and observing it in the ViewModel.

None

11.

Why might 'autoGenerate = true' be used with the '@PrimaryKey' annotation?

To enable foreign key constraints.

To automatically create entity classes.

To manage schema migrations automatically.

To auto-generate primary key values for new records.

None

12.

Which component in Room is responsible for defining SQL queries?

Entity

ViewModel

DAO

Repository

None

13.

Why is 'LiveData' used in Room database queries?

To ensure queries are executed on the main thread.

To improve database performance.

To observe and automatically update the UI with database changes.

To handle database transactions.

None

14.

What does the '@Insert' annotation in a DAO do?

Inserts new records into the database.

Executes a custom SQL query.

Updates existing records in the database.

Deletes records from the database.

None

15.

What is the purpose of the 'MainViewModelFactory' class?

To manage database migrations.

To provide a factory for creating ‘MainViewModel’ instances with an application context.

To define custom SQL queries.

To create instances of the Room database.

None

16.

What should be done to use the Database Inspector with a running Room database app?

Enable a debug mode in Room configuration.

Run the app on an emulator or connected device.

Connect to a physical device.

Enable ProGuard settings.

None