Spring data JPA fetch data as stream of list of Object

Question

I've a Spring web application which uses Spring Data JPA to interact with DB. I've a table consisting millions of records and I want to export a CSV consisting huge amount of data, for this I considered using Stream.

@Query(value = "SELECT * FROM table WHERE id=:id", nativeQuery = true)
public Stream<Object[]> getData(@Param("id") long id);

Executing query works fine and I get the data as stream but the problem occurs when I try to process the stream and I get ClassCastException ie BigInteger cannot be cast to Object . Can someone please suggest where I'm mistaking.

Answer 1

You got ClassCastException because it fetches only first field in select query which may be a numeric type. I have the same problem and updating spring-boot-starter-parent to version 1.4.1.RELEASE make it works. (spring-data-jpa: 1.10.3.RELEASE hibernate-core: 5.0.11.Final)