Eager Loading

Eager loading is a data loading strategy in software development where related data is fetched from a database in a single query or operation, rather than making separate queries as needed. It is commonly used in object-relational mapping (ORM) frameworks to optimize performance by reducing the number of database calls, especially when dealing with relationships like one-to-many or many-to-many. This approach helps prevent the N+1 query problem, where accessing related data for multiple objects results in excessive database hits.

Also known as: Preloading, Join Loading, Eager Fetch, Eager Load, Eagerly Loaded

Why learn Eager Loading?

Developers should use eager loading when building applications that require efficient data retrieval for related entities, such as in web APIs, reporting tools, or data-intensive dashboards. It is particularly beneficial in scenarios where you know in advance that related data will be needed, such as displaying a list of blog posts with their comments or user profiles with associated orders. By reducing database round-trips, eager loading improves application performance and scalability, especially under high load.

Learning Resources

• docs: Laravel Documentation: Eager Loading
• docs: Active Record Query Interface - Ruby on Rails Guides
• docs: Eager Loading in Entity Framework Core - Microsoft Docs
• video: Eager Loading vs Lazy Loading - YouTube Tutorial
• tutorial: The N+1 Query Problem Explained - FreeCodeCamp Article