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

To improve network performance.

To ensure the app’s UI remains responsive.

To reduce battery consumption.

To enable debugging features.

None

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

By storing data in SharedPreferences.

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

By directly accessing the database in the UI.

By setting up manual refresh methods in the DAO.

None

What is the purpose of the 'MainViewModelFactory' class?

To manage database migrations.

To define custom SQL queries.

To create instances of the Room database.

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

None

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

Repository

DAO

ViewModel

Database

None

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

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

Enable a debug mode in Room configuration.

Enable ProGuard settings.

Connect to a physical device.

Run the app on an emulator or connected device.

None

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

By writing raw SQL queries.

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

By directly instantiating the RoomDatabase class.

By creating a custom SQL engine.

None

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

To store search results for observed updates.

To create a backup of database data.

To define database table schemas.

To manage UI theme changes.

None

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

10.

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

To manage API calls.

To provide direct access to the database.

To abstract data operations and interact with the DAO.

To create UI components.

None

11.

Which library is required for handling asynchronous Room database queries?

Glide

Retrofit

Coroutines

Dagger

None

12.

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

launch() with Dispatchers.IO

AsyncTask()

runOnUiThread()

Thread.sleep()

None

13.

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

@Dao

@Database

@Entity

@Table

None

14.

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

15.

Why is 'LiveData' used in Room database queries?

To ensure queries are executed on the main thread.

To handle database transactions.

To improve database performance.

To observe and automatically update the UI with database changes.

None

16.

Which component in Room is responsible for defining SQL queries?

Entity

Repository

DAO

ViewModel

None