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 '@Insert' annotation in a DAO do?

Inserts new records into the database.

Deletes records from the database.

Updates existing records in the database.

Executes a custom SQL query.

None

Which library is required for handling asynchronous Room database queries?

Coroutines

Dagger

Retrofit

Glide

None

Which component in Room is responsible for defining SQL queries?

Repository

DAO

Entity

ViewModel

None

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

To enable debugging features.

To reduce battery consumption.

To ensure the app’s UI remains responsive.

To improve network performance.

None

Why is 'LiveData' used in Room database queries?

To improve database performance.

To observe and automatically update the UI with database changes.

To handle database transactions.

To ensure queries are executed on the main thread.

None

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

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

By directly instantiating the RoomDatabase class.

By writing raw SQL queries.

By creating a custom SQL engine.

None

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

To manage UI theme changes.

To define database table schemas.

To create a backup of database data.

To store search results for observed updates.

None

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

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

By directly accessing the database in the UI.

By storing data in SharedPreferences.

By setting up manual refresh methods in the DAO.

None

What is the purpose of the 'MainViewModelFactory' class?

To create instances of the Room database.

To manage database migrations.

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

To define custom SQL queries.

None

10.

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

@Database

@Table

@Dao

@Entity

None

11.

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

Repository

DAO

Database

ViewModel

None

12.

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

Enable ProGuard settings.

Connect to a physical device.

Enable a debug mode in Room configuration.

Run the app on an emulator or connected device.

None

13.

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

Prevents data loss during migrations.

Automatically updates the database schema without data loss.

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

Backs up the database before migration.

None

14.

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

To abstract data operations and interact with the DAO.

To provide direct access to the database.

To manage API calls.

To create UI components.

None

15.

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

launch() with Dispatchers.IO

AsyncTask()

Thread.sleep()

runOnUiThread()

None

16.

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

To enable foreign key constraints.

To auto-generate primary key values for new records.

To manage schema migrations automatically.

To automatically create entity classes.

None