{
    "name": "jpa-patterns",
    "version": "1.0.0",
    "description": "JPA/Hibernate patterns for entity design, relationships, query optimization, transactions, auditing, indexing, pagination, and pooling in Spring Boot. Use when designing JPA entities or relationships, or when a Hibernate query, transaction, or N+1 problem needs fixing.",
    "system_prompt": "name jpa-patterns description JPA/Hibernate patterns for entity design, relationships, query optimization, transactions, auditing, indexing, pagination, and pooling in Spring Boot. Use when designing JPA entities or relationships, or when a Hibernate query, transaction, or N+1 problem needs fixing. metadata {\"origin\":\"ECC\"} JPA/Hibernate Patterns Use for data modeling, repositories, and performance tuning in Spring Boot. When to Activate Designing JPA entities and table mappings Defining relationships (@OneToMany, @ManyToOne, @ManyToMany) Optimizing queries (N+1 prevention, fetch strategies, projections) Configuring transactions, auditing, or soft deletes Setting up pagination, sorting, or custom repository methods Tuning connection pooling (HikariCP) or second-level caching Entity Design @Entity @Table(name = \"markets\", indexes = { @Index(name = \"idx_markets_slug\", columnList = \"slug\", unique = true) }) @EntityListeners(AuditingEntityListener.class) public class MarketEntity { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; @Column(nullable = false, length = 200) private String name; @Column(nullable = false, unique = true, length = 120) private String slug; @Enumerated(EnumType.STRING) private MarketStatus status = MarketStatus.ACTIVE; @CreatedDate private Instant createdAt; @LastModifiedDate private Instant updatedAt; } Enable auditing: @Configuration @EnableJpaAuditing class JpaConfig {} Relationships and N+1 Prevention @OneToMany(mappedBy = \"market\", cascade = CascadeType.ALL, orphanRemoval = true) private List<PositionEntity> positions = new ArrayList <>(); Default to lazy loading; use JOIN FETCH in queries when needed Avoid EAGER on collections; use DTO projections for read paths @Query(\"select m from MarketEntity m left join fetch m.positions where m.id = :id\") Optional<MarketEntity> findWithPositions ( @Param(\"id\") Long id) ; Repository Patterns public interface MarketRepository extends JpaRepository <MarketEntity, Long> { Optional<MarketEntity> findBySlug (String slug) ; @Query(\"select m from MarketEntity m where m.status = :status\") Page<MarketEntity> findByStatus ( @Param(\"status\") MarketStatus status, Pageable pageable) ; } Use projections for lightweight queries: public interface MarketSummary { Long getId () ; String getName () ; MarketStatus getStatus () ; } Page<MarketSummary> findAllBy (Pageable pageable) ; Transactions Annotate service methods with @Transactional Use @Transactional(readOnly = true) for read paths to optimize Choose propagation carefully; avoid long-running transactions @Transactional public Market updateStatus (Long id, MarketStatus status) { MarketEntity entity = repo.findById(id) .orElseThrow(() -> new EntityNotFoundException ( \"Market\" )); entity.setStatus(status); return Market.from(entity); } Pagination PageRequest page = PageRequest.of(pageNumber, pageSize, Sort.by( \"createdAt\" ).descending()); Page<MarketEntity> markets = repo.findByStatus(MarketStatus.ACTIVE, page); For cursor-like pagination, include id > :lastId in JPQL with ordering. Indexing and Performance Add indexes for common filters ( status , slug , foreign keys) Use composite indexes matching query patterns ( status, created_at ) Avoid select * ; project only needed columns Batch writes with saveAll and hibernate.jdbc.batch_size Connection Pooling (HikariCP) Recommended properties: spring.datasource.hikari.maximum-pool-size=20 spring.datasource.hikari.minimum-idle=5 spring.datasource.hikari.connection-timeout=30000 spring.datasource.hikari.validation-timeout=5000 For PostgreSQL LOB handling, add: spring.jpa.properties.hibernate.jdbc.lob.non_contextual_creation=true Caching 1st-level cache is per EntityManager; avoid keeping entities across transactions For read-heavy entities, consider second-level cache cautiously; validate eviction strategy Migrations Use Flyway or Liquibase; never rely on Hibernate auto DDL in production Keep migrations idempotent and additive; avoid dropping columns without plan Testing Data Access Prefer @DataJpaTest with Testcontainers to mirror production Assert SQL efficiency using logs: set logging.level.org.hibernate.SQL=DEBUG and logging.level.org.hibernate.orm.jdbc.bind=TRACE for parameter values Remember : Keep entities lean, queries intentional, and transactions short. Prevent N+1 with fetch strategies and projections, and index for your read/write paths.",
    "model_config": {
        "provider": "deepseek",
        "model": "deepseek-chat",
        "temperature": 0.7,
        "max_tokens": 4096,
        "top_p": 0.9
    },
    "trigger_words": [],
    "source": "DeepseekModel",
    "source_url": "https://deepseekmodel.com/skill?id=affaan-m-ecc-skills-jpa-patterns-skill-md"
}