Hi, Prithvi, thanks for looking into this. In Hibernate 5.6.15.Final, please modify your test code like this

{{NativeQuery<Integer> query=session.createNativeQuery(sql); }}
query.addScalar( "user_id", StandardBasicTypes.INTEGER );
List<Integer> rsList = query.list();

Your test should work with or without the addScalar() call in Hibernate 5.6.15.Final, i.e.,

{{NativeQuery<Integer> query=session.createNativeQuery(sql); }}
List<Integer> rsList = query.list();