I'm using a Postgresql database. I connect to it using the Postgresql JPA driver, and use Spring-data CRUD repository to access it (with a custom query).
My Repository interface looks like this:
public interface MyRepository extends CrudRepository<MyEntity,MyEntity.Id> {
@Query(value = """
SELECT vin as vin FROM unnest(array[:vins]) as params(vin)
""", nativeQuery = true)
List<String> findUnknownVins(List<String> vins);
}
My custom query currently is not finished, but a minimal example which already fails. The query in the current state should just retrieve the vins that are provided as a parameter. Later on I want to use the query to retrieve unfound vins from the database.
But for now, this query already fails. When I execute it from a SQL Console, it works. But when I use it from my Repository, I get an exception:
org.postgresql.util.PSQLException: ERROR: a column definition list is required for functions returning "record"
The exception occurs at the unnest() function. To my understanding, with the "as params(vin)" I'm providing a column definition list, and Spring Data / JPA should be able to map the return value to a List.
