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?

Deletes records from the database.

Inserts new records into the database.

Updates existing records in the database.

Executes a custom SQL query.

None

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

By writing raw SQL queries.

By directly instantiating the RoomDatabase class.

By creating a custom SQL engine.

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

None

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

Backs up the database before migration.

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

Prevents data loss during migrations.

Automatically updates the database schema without data loss.

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

Why is 'LiveData' used in Room database queries?

To improve database performance.

To observe and automatically update the UI with database changes.

To ensure queries are executed on the main thread.

To handle database transactions.

None

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

launch() with Dispatchers.IO

AsyncTask()

Thread.sleep()

runOnUiThread()

None

What is the purpose of the 'MainViewModelFactory' class?

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

To create instances of the Room database.

To define custom SQL queries.

To manage database migrations.

None

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

Connect to a physical device.

Enable ProGuard settings.

Enable a debug mode in Room configuration.

Run the app on an emulator or connected device.

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 manage API calls.

To create UI components.

None

10.

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

To enable foreign key constraints.

To manage schema migrations automatically.

To auto-generate primary key values for new records.

To automatically create entity classes.

None

11.

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

To improve network performance.

To enable debugging features.

To ensure the app’s UI remains responsive.

To reduce battery consumption.

None

12.

Which library is required for handling asynchronous Room database queries?

Glide

Coroutines

Dagger

Retrofit

None

13.

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

@Table

@Dao

@Entity

@Database

None

14.

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

Database

ViewModel

Repository

DAO

None

15.

Which component in Room is responsible for defining SQL queries?

DAO

ViewModel

Entity

Repository

None

16.

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