In case a value of a binded query parameter is null and is used with coalesce the following error is throw:

org.postgresql.util.PSQLException: ERROR: COALESCE types bytea and character varying cannot be matched

TypedQuery<Person> query = entityManager.createQuery("from Person p where p.name = coalesce(:name , p.name) ", Person.class);
			query.setParameter("name", null);
			List<Person> resultList = query.getResultList();