Watch Mouse: Retrieving the data as List from HQL

Retrieving the data from the query as collection of pair.

Suppose the query is "Select username, count(id)..". If the query

returns a list String, Long pair then the query actually

returns it as list<Object[]>. So collect the result in a

variable List<Object[]>.

And then iterate over the object array. To get the values,

Cast the corresponding object.

 Query q1 = em.createQuery("SELECT e.name, e.salary

 FROM Employee e");
    List&lt;Object[]&gt; result1 = q1.getResultList();
    for (Object[] resultElement : result1) {
        String name = (String)resultElement[0];
        Double salary = (Double)resultElement[1];
        ...
    }

    Query q2 = em.createQuery("SELECT e.name, e.salary,

e.department FROM Employee e");
    List&lt;Object[]&gt; result2 = q2.getResultList();
    for (Object[] resultElement : result2) {
        String name = (String)resultElement[0];
        Double salary = (Double)resultElement[1];
        Department dept = (Department)resultElement[2];
        ...
    }

    Query q3 = em.createQuery("SELECT COUNT(e),

SUM(e.salary) FROM Employee e");
    Object[] result3 = (Object[])q3.getSingleResult();
    Long count = (Long)result3[0];
    Double sum = (Double)result3[1];