Using ________ type of loading for related entities can significantly affect performance in Entity Framework.
- Lazy
- Eager
- Deferred
- Explicit
The correct option is "Eager". Eager loading retrieves all related entities in a single query, which can lead to performance issues.
Optimizing the ________ of entities can help improve query performance in Entity Framework.
- Structure
- Properties
- Relationships
- Mapping
The correct option is "Properties". Optimizing the properties of entities, such as selecting only necessary columns, can boost performance.
To optimize query performance, Entity Framework can pre-generate views using ________.
- Code-First Migrations
- Database Views
- Model-First Approach
- Stored Procedures
Entity Framework can pre-generate views using database views. This technique helps in improving query performance by reducing the overhead of dynamically generating SQL queries during runtime.
For complex queries, using ________ over LINQ can sometimes result in better performance in Entity Framework.
- Entity SQL
- Object-SQL Mapping
- Raw SQL Queries
- Stored Procedures
In Entity Framework, using raw SQL queries directly instead of LINQ can sometimes lead to better performance, especially for complex queries, as it allows developers to optimize the query execution plan.
In a scenario with high transaction rates, what Entity Framework strategies can be employed to optimize performance?
- Optimistic concurrency control
- Batch processing
- Database sharding
- Connection resiliency
Option 4, Connection resiliency, involves techniques such as connection pooling and retry logic to handle transient failures, ensuring that the application remains responsive even under high transaction rates. These strategies help optimize performance by efficiently managing connections and ensuring the application's resilience to temporary network issues.
Consider a situation where an Entity Framework application experiences slow response times due to large object graphs. How would you address this for performance improvement?
- Lazy loading
- Eager loading
- Proxy generation
- Entity splitting
Option 2, Eager loading, retrieves related entities along with the main entity in a single query, reducing the number of database round trips and mitigating the impact of large object graphs on performance. By eagerly loading related data, the application can fetch all necessary information upfront, improving response times and overall performance, especially in scenarios with large object graphs.
How would you optimize an Entity Framework application that requires frequent data writes and reads from a high-latency database?
- Asynchronous programming
- Database indexing
- Connection pooling
- Query caching
Option 1, Asynchronous programming, allows the application to perform multiple operations concurrently, reducing the impact of latency on performance. By utilizing asynchronous programming techniques such as async/await, the application can continue executing other tasks while waiting for database operations to complete, thereby improving overall responsiveness and throughput, especially in scenarios involving frequent data reads and writes to a high-latency database.
What type of caching is natively supported by Entity Framework?
- Eager loading
- Explicit loading
- Lazy loading
- No caching
Entity Framework natively supports eager loading, which is the process of loading related entities along with the main entity being queried. This helps reduce the number of database queries by fetching all required data in a single query, enhancing performance.
How does Entity Framework utilize caching when retrieving the same entity multiple times in a single context?
- It caches entities only once per context and serves subsequent requests from memory.
- It invalidates the cache and fetches the entity again from the database.
- It re-executes the query against the database each time the entity is requested, ensuring data freshness.
- It stores entities in memory for the duration of the context, allowing quick retrieval when requested again.
Entity Framework utilizes the first-level cache, also known as the ObjectStateManager, to store entities retrieved during a context's lifespan. When an entity is requested multiple times within the same context, Entity Framework fetches it from the cache rather than executing a new query, improving performance.
What happens in Entity Framework when you query an entity that has already been retrieved in the current context?
- It fetches the entity from the database again, ignoring any previously retrieved instances.
- It merges the changes from the database into the tracked entity, ensuring data consistency.
- It returns the entity from the cache, avoiding a database round trip.
- It throws an exception indicating that the entity is already being tracked by the context.
Entity Framework utilizes its change tracking mechanism to detect changes made to entities within the context. When an entity is queried again, Entity Framework returns the already retrieved instance from the cache, ensuring data consistency and avoiding unnecessary database queries.