title: Load property of entity using spring-data-jpa query methods
body: <p>For example, I have entity <code>User</code> with fields <code>id</code>, <code>active</code> and 10 more.
  How could I get all active Users? Easy:</p>
  
  <pre><code>public interface UserRepository extends JpaRepository&lt;User, Integer&gt; {
      List&lt;User&gt; findAllByActiveTrue();
  }
  </code></pre>
  
  <p>How could I load list of <code>id</code> of active users? I need a <code>@Query</code> annotation to write JPQL by myself, like this:</p>
  
  <pre><code>public interface UserRepository extends JpaRepository&lt;User, Integer&gt; {
      @Query("select u.id from User u where u.active = true")
      List&lt;Integer&gt; fetchActiveUsersIds();
  }
  </code></pre>
  
  <p><strong>My question is</strong>: could I name somehow a method to avoid writing JQPL by myself, like in first case?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>I need something like this:</p>
  
  <pre><code>public interface UserRepository extends JpaRepository&lt;User, Integer&gt; {
      List&lt;Integer&gt; findAll_Id_ByActiveTrue();
  }
  </code></pre>