'Is there a way to return collection instead of entity in @Repository's @Query

I have a query:

@Query(
    value = "select name, age, now() from received.scheme ;", 
    nativeQuery = true

)
public {???} selectData()

I cannot create or return an entity for such a scheme as there is no natural id in it, so is there a way to return something like List<Triple<String, Int, LocalDateTime>>?

javasqlspringhibernatespring-data-jpa


Solution 1:[1]

you can create another class with the required properties which you want to retrieve from the database and then you can return that class as List<Class>.

Solution 2:[2]

In your code you get the data from: scheme So the Entity SchemeEntity should contains those three fields:

  1. name
  2. age
  3. now (creationDate for example it depend on your logic)

Then your method should be like this:

@Query(value = "select name, age, now() from received.scheme ;", 
    nativeQuery = true
)
public List<SchemeEntity> selectData();

Solution 3:[3]

You can provide a PROJECTION entity which will have 3 attributes and must provide a parametrized constructor with those 3 attributes you want to fetch ,or you can still get them as a List<Object[]> and then hydrate your entity.

Solution 4:[4]

I've tried those things but what worked for me is using ctid as an @Id. Since I only needed some sort of a mock id, it worked fine.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 rg226965
Solution 2 Mohamed Aymen Charrada
Solution 3 karim farhouti
Solution 4 Jhanzaib Humayun

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