The ________ method of DbContext can be overridden to configure domain classes using Fluent API.
- Configure
- Customize
- Mapping
- OnModelCreating
In Entity Framework, the OnModelCreating method of DbContext can be overridden to configure domain classes using Fluent API. This method is called when the model for a derived context has been initialized, allowing you to specify how the model should be configured.
In Entity Framework, ________ loading can be achieved by using the Include method with DbSet queries.
- Deferred
- Eager
- Immediate
- Lazy
In Entity Framework, eager loading can be achieved by using the Include method with DbSet queries. Eager loading allows you to retrieve related entities along with the main entities in a single query, reducing the number of database round trips and improving performance.
When detaching entities from the context, ________ method of DbContext is commonly used.
- Detach
- Dispose
- Remove
- Unload
The correct method is Detach. When you detach an entity from the context, it will no longer be tracked by the context for changes. This can be useful when you want to manipulate an entity outside of the context's scope.
To handle optimistic concurrency in Entity Framework, the ________ attribute is used on entity properties.
- ConcurrencyCheck
- OptimisticConcurrency
- Timestamp
- Version
The correct attribute is ConcurrencyCheck. Adding this attribute to properties ensures that Entity Framework checks for concurrency conflicts when updating or deleting rows in the database, ensuring data integrity in a multi-user environment.
In a disconnected scenario, the ________ method of DbSet is used to update an existing entity.
- Attach
- Modify
- Refresh
- Update
The correct method is Attach. In a disconnected scenario, when you have an entity that was not originally tracked by the context, you use the Attach method to attach it to the context so that any changes made to it can be persisted back to the database.
In a scenario where multiple users are modifying the same data, how does DbContext ensure data integrity?
- Automatic conflict resolution
- Explicit locking
- Optimistic concurrency control
- Pessimistic concurrency control
DbContext utilizes optimistic concurrency control to ensure data integrity in scenarios where multiple users are modifying the same data. This approach relies on versioning and optimistic locking to detect and handle conflicts, minimizing the risk of data inconsistency.
When implementing a complex transaction involving multiple DbSet operations, how does DbContext manage these operations to ensure data consistency?
- DbContext applies compensating transactions for rollback
- DbContext employs distributed transactions for consistency
- DbContext ensures atomicity of transactions
- DbContext uses savepoints to isolate operations
DbContext ensures atomicity of transactions when dealing with complex transactions involving multiple DbSet operations. This ensures that either all operations within the transaction are successfully completed, or none of them are, maintaining data consistency.
In which approach do you create database tables directly from your code models?
- Code First
- Database First
- Entity First
- Model First
Code First approach involves creating database tables directly from code models. It allows developers to define their domain model using C# or VB.NET classes, and the database schema is generated based on these classes during runtime. This approach provides flexibility and control over the database schema, making it suitable for scenarios where the database evolves with the application.
Which Entity Framework approach involves designing the database schema in a visual designer before generating the code?
- Code First
- Database First
- Entity First
- Model First
Model First approach involves designing the database schema visually using Entity Framework Designer in Visual Studio before generating the code. Developers can create entity types, relationships, and mappings using the designer, and then the corresponding code classes are generated from the model. This approach is useful when the database schema is finalized early in the development process.
Which approach requires the database to be designed first, followed by the generation of entity classes?
- Code First
- Database First
- Entity First
- Model First
Database First approach requires the database schema to be designed first using tools like SQL Server Management Studio or other database design tools. Then, Entity Framework generates entity classes based on the existing database schema. This approach is suitable for scenarios where the database already exists or when working with legacy databases.