java 31 lines · 8 steps

Deriving JPA queries from method names in Spring

Spring Data JPA generates real SQL from repository method names, so a naming convention replaces hand-written queries.

Explained by highlit

Spring Intermediate query derivation repositories pagination orm convention over configuration

1package com.example.shop.repository;
2 
3import com.example.shop.domain.Order;
4import com.example.shop.domain.OrderStatus;
5import org.springframework.data.domain.Page;
6import org.springframework.data.domain.Pageable;
7import org.springframework.data.jpa.repository.JpaRepository;
8import org.springframework.stereotype.Repository;
9 
10import java.math.BigDecimal;
11import java.time.Instant;
12import java.util.List;
13import java.util.Optional;
14 
15@Repository
16public interface OrderRepository extends JpaRepository<Order, Long> {
17 
18    List<Order> findByCustomerIdOrderByCreatedAtDesc(Long customerId);
19 
20    Page<Order> findByStatusAndTotalGreaterThanEqual(OrderStatus status, BigDecimal minTotal, Pageable pageable);
21 
22    Optional<Order> findFirstByCustomerIdAndStatusOrderByCreatedAtDesc(Long customerId, OrderStatus status);
23 
24    List<Order> findByStatusInAndCreatedAtBetween(List<OrderStatus> statuses, Instant from, Instant to);
25 
26    boolean existsByReferenceIgnoreCase(String reference);
27 
28    long countByCustomerIdAndStatus(Long customerId, OrderStatus status);
29 
30    List<Order> findTop10ByCustomerCountryAndStatusNotOrderByTotalDesc(String country, OrderStatus excludedStatus);
31}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Method names in a Spring Data repository are parsed into queries, so structure beats boilerplate.
2Return types shape behavior: Optional guards absence, Page adds paging metadata, List returns everything.
3Keywords like In, Between, GreaterThanEqual, and Top10 express filtering, ranges, and limits without any SQL.

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