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 manage schema migrations automatically.

To auto-generate primary key values for new records.

To automatically create entity classes.

To enable foreign key constraints.

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

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

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

By creating a custom SQL engine.

By writing raw SQL queries.

By directly instantiating the RoomDatabase class.

None

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

To provide direct access to the database.

To abstract data operations and interact with the DAO.

To create UI components.

To manage API calls.

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

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

To ensure the app’s UI remains responsive.

To enable debugging features.

To reduce battery consumption.

To improve network performance.

None

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

By setting up manual refresh methods in the DAO.

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

By storing data in SharedPreferences.

By directly accessing the database in the UI.

None

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

Repository

Database

ViewModel

DAO

None

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

Updates existing records in the database.

Inserts new records into the database.

Executes a custom SQL query.

Deletes records from the database.

None

10.

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

Connect to a physical device.

Enable a debug mode in Room configuration.

Enable ProGuard settings.

Run the app on an emulator or connected device.

None

11.

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

To create a backup of database data.

To manage UI theme changes.

To define database table schemas.

To store search results for observed updates.

None

12.

Which component in Room is responsible for defining SQL queries?

Repository

ViewModel

DAO

Entity

None

13.

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

@Dao

@Database

@Table

@Entity

None

14.

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

Thread.sleep()

AsyncTask()

launch() with Dispatchers.IO

runOnUiThread()

None

15.

Which library is required for handling asynchronous Room database queries?

Coroutines

Retrofit

Glide

Dagger

None

16.

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

Prevents data loss during migrations.

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

Backs up the database before migration.

Automatically updates the database schema without data loss.

None