How to choose a Spring #Query annotation to suit the DB (e.g. HSQLDB, Postgres)? - spring-data-jpa

Question

Say I have this annotated Java code:
#Transactional
public interface EventRepository extends JpaRepository<Event, Long> {
#Query("from Event where path like ?1% and date(start_time)=CURRENT_DATE")
Stream<Event> findAllChildrenToday(String path);
This works for Postgres. However, when running unit tests I want to use an in-memory database such as HSQLDB. Unfortunately the SQL date(...) command doesn't work on HSQLDB, so I really need something that changes query according to the database like the following in which I've made up an imaginary "db=" tag:
#Query(db="Postgres", "from Event where path like ?1% and date(start_time)=CURRENT_DATE")
#Query(db="HSQLDB", "from Event where path like ?1% and start_time >= CURRENT_DATE and (start_time < CURRENT_DATE + 1)")
Stream<Event> findAllChildrenToday(String path);
How do I do this for real?
I'm not too familiar with Spring so please be fairly detailed in your answers. Thanks.

Answer 1

You can make the following trick with Spring profiles:
#NoRepositoryBean
public interface EventRepo extends JpaRepository<Event, Long> {
Stream<Event> findAllChildrenToday(String path);
}
#Profile("postgres")
public interface PostgresRepo extends EventRepo {
#Override
#Query(/* a postgres specific query */)
Stream<Event> findAllChildrenToday(String path);
}
#Profile("hsqldb")
public interface HsqldbRepo extends EventRepo {
#Override
#Query(/* a hsqldb specific query */)
Stream<Event> findAllChildrenToday(String path);
}
Then in your service (or controller):
#Service
public class EventService {
#Autowired
private EventRepo eventRepo;
//...
}
In the application.properties file you set 'postgres' profile (this profile will be used by default in the production):
spring.profiles.active=postgres
And in your IDE you set 'hsqldb' profile: -Dspring.profiles.active=hsqldb (as JVM option).
Thanks to this the repo injection will depend on the used Spring profile.