title: jpa @Inheritance(strategy=InheritanceType.JOINED) how to select super entity not contain child
body: <p>I have question: Let's assume I have two classes User and person, person extends User. In User I have <code>@Inheritance(strategy=InheritanceType.JOINED)</code>. Sometimes I only want to select the user info not contain the child table info,</p>
  
  <p>User.java(super class)</p>
  
  <pre><code>@Entity
  @Inheritance(strategy=InheritanceType.JOINED)
  @DiscriminatorColumn(name = "user_type")
  @Table(name = "users")
  public class User {.........}
  </code></pre>
  
  <p>Person.java</p>
  
  <pre><code>@Entity
  public class Person extends User {......}
  </code></pre>
  
  <p>Company.java</p>
  
  <pre><code>@Entity
  public class Company extends User {.............}
  </code></pre>
  
  <p>UserRepository.java</p>
  
  <pre><code>@Transactional
  public interface UserRepository extends UserBaseRepository&lt;User&gt; {
  
  //@Query(value="select u from User u where u.email=?1")
  @Query(value="select u.id,u.email from User u where u.email=?1")
  User getUser(String email);
  
  @Query("select u from User u where u.email=?1")
  User getUser2(String email);
  
  @Query(value="select * from Users where email=:email",nativeQuery=true)
  User getUser3(String email);
  }
  </code></pre>
  
  <p>The following exception occurs:</p>
  
  <pre><code>Hibernate: select user0_.id as col_0_0_, user0_.email as col_1_0_ from users user0_ where user0_.email=?
  org.springframework.core.convert.ConversionFailedException: Failed to convert from type java.lang.Object[] to type netgloo.models.User for value '{1, 635@qq.com}';
  nested exception is org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type java.lang.Long to type netgloo.models.User
  </code></pre>
  
  <ol>
  <li>how to  get the user info not contain Person,Company</li>
  <li>how to  get the Person info not contain user ,Company</li>
  </ol>