Select top 1 result using JPA

Question

I need to bring from DB only one single result. How can I do that with JPA?

Select top 1 * from table

I tried

"select t from table t"

query.setMaxResults(1);

query.getSingleResult();

but didn't work. Any other ideas?

Answer 1

Try like this

String sql = "SELECT t FROM table t";
Query query = em.createQuery(sql);
query.setFirstResult(firstPosition);
query.setMaxResults(numberOfRecords);
List result = query.getResultList();

It should work

UPDATE*

You can also try like this

query.setMaxResults(1).getResultList();

Answer 2

To use getSingleResult on a TypedQuery you can use

query.setFirstResult(0);
query.setMaxResults(1);
result = query.getSingleResult();

Answer 3

2021 att: you can use TOP or FIRST in Spring Data JPA

example:

User findFirstByOrderByLastnameAsc();

User findTopByOrderByAgeDesc();

Page<User> queryFirst10ByLastname(String lastname, Pageable pageable);

Slice<User> findTop3ByLastname(String lastname, Pageable pageable);

List<User> findFirst10ByLastname(String lastname, Sort sort);

List<User> findTop10ByLastname(String lastname, Pageable pageable);

doc: https://docs.spring.io/spring-data/jpa/docs/2.5.4/reference/html/#repositories.limit-query-result

Answer 4

The easiest way is by using @Query with NativeQuery option like below:

@Query(value="SELECT 1 * FROM table ORDER BY anyField DESC LIMIT 1", nativeQuery = true)

Answer 5

Use a native SQL query by specifying a @NamedNativeQuery annotation on the entity class, or by using the EntityManager.createNativeQuery method. You will need to specify the type of the ResultSet using an appropriate class, or use a ResultSet mapping.

Answer 6

Use Pageable with size is 1 and sort by the field you want it should work

  @Query("from Cat t order by t.name desc")
  Page<Cat> findCats(Pageable page);

the page should be use is

Pageable page = PageRequest.of(0, 1, Sort.by(Sort.Direction.DESC, "name"));