Spring Data JPA, Hibernate ORM & N+1 Query Optimization
Master Object-Relational Mapping (ORM) with Hibernate, Spring Data JPA repositories, `@Entity`, `@OneToMany`, `@ManyToOne`, JPQL queries, and resolving N+1 performance bottlenecks with `JOIN FETCH`.
Spring Data JPA & The N+1 Select Problem
### The N+1 Select Problem & Solution
When fetching a list of N parent entities with LAZY child associations, accessing child elements triggers **N additional SELECT queries**!
- **Fix**: Use `JOIN FETCH` in JPQL or `@EntityGraph` to retrieve parent and children in a single unified SQL JOIN query!
