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.

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

launch() with Dispatchers.IO

runOnUiThread()

AsyncTask()

Thread.sleep()

None

Which component in Room is responsible for defining SQL queries?

DAO

ViewModel

Entity

Repository

None

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

Deletes records from the database.

Executes a custom SQL query.

Updates existing records in the database.

Inserts new records into the database.

None

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

Backs up the database before migration.

Prevents data loss during migrations.

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

Automatically updates the database schema without data loss.

None

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

By creating a custom SQL engine.

By writing raw SQL queries.

By directly instantiating the RoomDatabase class.

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

None

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

Enable ProGuard settings.

Enable a debug mode in Room configuration.

Connect to a physical device.

Run the app on an emulator or connected device.

None

Why is 'LiveData' used in Room database queries?

To observe and automatically update the UI with database changes.

To handle database transactions.

To improve database performance.

To ensure queries are executed on the main thread.

None

What is the purpose of the 'MainViewModelFactory' class?

To define custom SQL queries.

To manage database migrations.

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

To create instances of the Room database.

None

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

@Entity

@Database

@Table

@Dao

None

10.

Which library is required for handling asynchronous Room database queries?

Dagger

Coroutines

Glide

Retrofit

None

11.

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

To auto-generate primary key values for new records.

To manage schema migrations automatically.

To enable foreign key constraints.

To automatically create entity classes.

None

12.

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

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

By setting up manual refresh methods in the DAO.

By storing data in SharedPreferences.

By directly accessing the database in the UI.

None

13.

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

Database

Repository

ViewModel

DAO

None

14.

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

To define database table schemas.

To store search results for observed updates.

To manage UI theme changes.

To create a backup of database data.

None

15.

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

To reduce battery consumption.

To improve network performance.

To ensure the app’s UI remains responsive.

To enable debugging features.

None

16.

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

To provide direct access to the database.

To manage API calls.

To create UI components.

To abstract data operations and interact with the DAO.

None