How to get aggregation function request using spring -data-jpa

Question

I am using Spring jpa 1.2 data, and I still cannot find the result of the generic query, like the following.

select count(v), date(v.createTimestamp) from UserEntity v group by date(v.createTimestamp) 

What works great with embedded JPA

 @Entity() public class UserEntity { @Id private long id; . . @Column(columnDefinition = "TIMESTAMP DEFAULT CURRENT_TIMESTAMP") private Timestamp createTimestamp; } 

any my jpa repository

 public interface UserRepository extends JpaRepository<UserEntity, Long>, JpaSpecificationExecutor<UserEntity> { } 

since I can execute aggregate throw spring data queries, I don't see anything in the documentation

Answer 1

I found a way to do this

 public interface UserRepository extends JpaRepository<UserEntity, Long>, JpaSpecificationExecutor<UserEntity> { @Query(value = "select count(v), date(v.createTimestamp) from UserEntity v group by date(v.createTimestamp)", countQuery = "select count(1) from (select count(1) from UserEntity v group by date(v.createTimestamp)) z") public List<Object[]> findCountPerDay(); } 

Thus, we can obtain aggregate data together with the actual account (aggregated records)

Answer 2

"countBy" is currently not supported in Spring Data:

Support for countBy request methods

Does Spring Data JPA have any way to count questions using method name resolution?

Answer 3

You may have @Query for custom queries for unsupported methods in spring-data.

Answer 4

you can also use the @NativeQuery option