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copied!<p>You can create any object in your QL using the "new" syntax - your class just needs a constructor that takes the values returned by your query.</p> <p>For example, with a class like DepartmentEmployeeCount, with a constructor:</p> <pre><code>public DepartmentEmployeeCount(String departmentName, Integer employeeCount) </code></pre> <p>you could use QL something like:</p> <pre><code>SELECT NEW DepartmentEmployeeCount(D.DEPARTMENT_NAME, count(E.id)) from Department D left join D.employees E GROUP BY D.DEPARTMENT_NAME </code></pre> <p>Or if you were just selecting the count(*) you could simply cast the query result to a Number.</p> <p>Alternatively, to do the same without the DepartmentEmployeeCount class, you could leave out the NEW, so:</p> <pre><code>SELECT D.DEPARTMENT_NAME, count(E.id) </code></pre> <p>This would return a <code>List<Object[]></code> where each list item was an array of 2 elements, departmentName and count.</p> <p>To answer your later question in the comments, to populate all fields of a Department plus a transient employeeCount field, one suggestion would be to do 2 queries. This would still be more efficient than your original query (a subselect for each employee count).</p> <p>So one query to read the departments</p> <pre><code>SELECT D from Department D </code></pre> <p>giving you a <code>List<Department></code></p> <p>Then a 2nd query returning a temporary array:</p> <pre><code>SELECT D.DEPARTMENT_ID, count(E.id) from Department D left join D.employees E GROUP BY D.DEPARTMENT_ID </code></pre> <p>giving you a <code>List<Object[]></code> with DEPARTMENT_ID and count in it.</p> <p>Then you use the 2nd list to update the transient count property on your first list. (You could try selecting into a Map to make this lookup easier, but I think that's a Hibernate feature).</p>

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