title: Spring data : CrudRepository's save method and update
body: <p>I wanted to know if the <code>{save}</code> method in <code>CrudRepository</code> do an update if it finds already the entry in the database like : </p>
  
  <pre><code>@Repository
  public interface ProjectDAO extends CrudRepository&lt;Project, Integer&gt; {}
  
  @Service
  public class ProjectServiceImpl {
  
  @Autowired private ProjectDAO pDAO;
  
  public void save(Project p) { pDAO.save(p); } }
  </code></pre>
  
  <p>So if I call that method on an already registred entry, it'll update it if it finds a changed attribute ?</p>
  
  <p>Thanks.</p>