What behavior can be expected when applying the LAZY data loading strategy in an ORM environment?

When using the LAZY data loading strategy in an ORM environment, objects related to the main entity are not loaded immediately upon selection. Instead, they are loaded only upon the first access to these related data.

This helps reduce the initial load on the database and speeds up loading of the main data, especially if related data is not always needed.

However, it is important to consider:

• The first access to lazily loaded data will trigger a separate query to the database, which can lead to the "N+1 query" problem.
• In some cases, if the session or ORM context is closed, accessing lazily loaded data will cause an error.

Example in Java with JPA:

@Entity
public class User {
    @OneToMany(fetch = FetchType.LAZY)
    private List<Order> orders;
}

// When loading User, orders are not loaded immediately.
User user = entityManager.find(User.class, userId);
// Accessing user.getOrders() will trigger a separate database query.

Thus, LAZY loading helps optimize performance but requires careful management of sessions and understanding of ORM behavior.