Retrieve Multiple Properties

If you would like to retrieve more than one property, but still not the entire object, you can comma-separate the requested properties within a SELECT statement.

    String queryString = "SELECT s.firstName, s.lastName FROM Staff s";

    List<Object[]> results = em.createQuery(queryString, Object[].class)
                               .getResultList();

Practice Exercise

Notice that the second argument to createQuery is now Object[].class and the collection is typed as List<Object[]>. Each row that returns from the query is placed into its own Object[]. In our case index 0 would hold the firstName value and index 1 would hold the lastName value. If we wanted to print off the result list we could access the data as follows:

String queryString = "SELECT s.firstName, s.lastName FROM Staff s";

List<Object[]> results = em.createQuery(queryString, Object[].class)
                          .getResultList();
for(Object[] arr : results){
  System.out.println("First name: " + arr[0] + " Last name: " + arr[1]);
}

Drill

1. In your JPQLClient class, write a JPQL statement to retrieve the firstName and lastName of any staff member whose id is less than 10.
2. Iterate over the returned collection and print off the results.

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