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  Query query = em.createQuery("SELECT c from Customer c");
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  query = em.createNamedQuery("findCustomerByName");
  query.setParameter("name", "t,om");
  query.setMaxResults(10);
  query.setFirstResult(3);
  List customers = query.getResultList();
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  SELECT o from Order i WHERE i.orderNo = ?1
  query.setParameter(1, 100.00);
  SELECT o from Order i WHERE o.price = :price
  query.setParameter("price", 100.00);
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  query.getSingleResult();
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  WHERE c.orders IS EMPTY
  WHERE CONCAT(c.fname, c.lname) = 't,om'
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  SELECT o from Order I WHERE o.customer


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