java 49 lines · 8 steps

Keyset pagination with Spring Data JPA

Cursor-based paging that stays fast on deep pages by seeking past the last row instead of counting offsets.

Explained by highlit

Spring Advanced pagination cursor jpa query tie-breaker

1@Repository
2public interface OrderRepository extends JpaRepository<Order, Long> {
3 
4    @Query("""
5        select o from Order o
6        where o.customerId = :customerId
7          and (o.createdAt < :lastCreatedAt
8               or (o.createdAt = :lastCreatedAt and o.id < :lastId))
9        order by o.createdAt desc, o.id desc
10        """)
11    List<Order> findNextPage(
12            @Param("customerId") Long customerId,
13            @Param("lastCreatedAt") Instant lastCreatedAt,
14            @Param("lastId") Long lastId,
15            Pageable pageable);
16 
17    @Query("""
18        select o from Order o
19        where o.customerId = :customerId
20        order by o.createdAt desc, o.id desc
21        """)
22    List<Order> findFirstPage(@Param("customerId") Long customerId, Pageable pageable);
23}
24 
25@Service
26@RequiredArgsConstructor
27class OrderPageService {
28 
29    private final OrderRepository orders;
30 
31    KeysetPage<Order> loadPage(Long customerId, String cursor, int size) {
32        Pageable limit = PageRequest.of(0, size + 1);
33        List<Order> rows = (cursor == null)
34                ? orders.findFirstPage(customerId, limit)
35                : loadAfter(customerId, Cursor.decode(cursor), limit);
36 
37        boolean hasNext = rows.size() > size;
38        List<Order> page = hasNext ? rows.subList(0, size) : rows;
39        String nextCursor = hasNext
40                ? Cursor.encode(page.get(page.size() - 1))
41                : null;
42 
43        return new KeysetPage<>(page, nextCursor);
44    }
45 
46    private List<Order> loadAfter(Long customerId, Cursor c, Pageable limit) {
47        return orders.findNextPage(customerId, c.createdAt(), c.id(), limit);
48    }
49}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Keyset pagination seeks by the last row's values rather than skipping N rows, keeping deep pages cheap.
2Ordering on a non-unique column needs a unique tie-breaker like the id to make the cursor deterministic.
3Fetching size + 1 rows tells you whether a next page exists without a separate count query.

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