ASP.NET Core Entity Framework Core 2

Question 1

What does AsNoTracking() do in an EF Core LINQ query?

Accepted Answer

Returns entities without adding them to the change tracker, improving read performance

Answer

Disables lazy loading for the query

Answer

Prevents the query from being cached

Answer

Marks entities as read-only in the schema

Question 2

Which EF Core method applies pending migrations to the database?

Accepted Answer

dotnet ef database update

Answer

dotnet ef migrations apply

Answer

dotnet ef db migrate

Answer

dotnet ef schema update

Question 3

What is the purpose of the Fluent API in Entity Framework Core?

Accepted Answer

To configure entity mappings and relationships in OnModelCreating using method chaining

Answer

To write raw SQL with a fluent syntax

Answer

To define navigation properties on entities

Answer

To configure DI for EF Core services

Question 4

Which EF Core loading strategy fetches related entities in the same query using a JOIN?

Accepted Answer

Eager loading with Include()

Answer

Lazy loading

Answer

Explicit loading with Load()

Answer

Deferred loading

Question 5

What does the [Key] attribute do on an entity property in EF Core?

Accepted Answer

Designates the property as the primary key for the entity

Answer

Creates a database index on the column

Answer

Marks the property as required

Answer

Encrypts the column value

Question 6

Which EF Core query returns only the first matching entity or null if not found?

Accepted Answer

FirstOrDefaultAsync()

Answer

SingleOrDefaultAsync()

Answer

FindAsync()

Answer

FirstAsync()