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.

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 automatically create entity classes.

To enable foreign key constraints.

None

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

By directly instantiating the RoomDatabase class.

By writing raw SQL queries.

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

By creating a custom SQL engine.

None

Which library is required for handling asynchronous Room database queries?

Retrofit

Dagger

Coroutines

Glide

None

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

Connect to a physical device.

Run the app on an emulator or connected device.

Enable ProGuard settings.

Enable a debug mode in Room configuration.

None

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

To create a backup of database data.

To define database table schemas.

To store search results for observed updates.

To manage UI theme changes.

None

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

launch() with Dispatchers.IO

runOnUiThread()

AsyncTask()

Thread.sleep()

None

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

To manage API calls.

To create UI components.

To provide direct access to the database.

To abstract data operations and interact with the DAO.

None

What is the purpose of the 'MainViewModelFactory' class?

To create instances of the Room database.

To manage database migrations.

To define custom SQL queries.

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

None

Which component in Room is responsible for defining SQL queries?

DAO

Entity

ViewModel

Repository

None

10.

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

11.

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

To ensure the app’s UI remains responsive.

To reduce battery consumption.

To enable debugging features.

To improve network performance.

None

12.

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

By storing data in SharedPreferences.

By setting up manual refresh methods in the DAO.

By directly accessing the database in the UI.

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

None

13.

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

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

Prevents data loss during migrations.

Backs up the database before migration.

Automatically updates the database schema without data loss.

None

14.

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

@Database

@Table

@Entity

@Dao

None

15.

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

Repository

DAO

Database

ViewModel

None

16.

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

Executes a custom SQL query.

Updates existing records in the database.

Inserts new records into the database.

Deletes records from the database.

None