休眠 - 只獲取元素的最新版本中包含集合

Question

我有一個實體：

@Entity 
@DiscriminatorValue("News") 
public class News extends TVProduction { 
private int audience; 
private Collection<Reportage> reportages; 

public News() { 
    super(); 
    setAudience(0); 
} 

@Column(name = "audience") 
public int getAudience() { 
    return audience; 
} 

public void setAudience(int audience) { 
    this.audience = audience; 
} 

@OneToMany 
@JoinTable(name = "Reportages_News", 
     joinColumns = @JoinColumn(name = "news_id"), 
     inverseJoinColumns = @JoinColumn(name = "reportage_id") 
) 
public Collection<Reportage> getReportages() { 
    return reportages; 
} 

public void setReportages(Collection<Reportage> reportages) { 
    this.reportages = reportages; 
} 

}

而且報告文學類看起來是這樣的：

@Entity 
@Table(name = "Reportage") 
public class Reportage { 
private Long id; 
private String subject; 
private int version; 
private String content; 
private Reporter reporter; 

public String getSubject() { 
    return subject; 
} 

public void setSubject(String subject) { 
    this.subject = subject; 
} 

public int getVersion() { 
    return version; 
} 

public void setVersion(int version) { 
    this.version = version; 
} 

public String getContent() { 
    return content; 
} 

public void setContent(String content) { 
    this.content = content; 
} 

@Id 
@GeneratedValue(strategy = GenerationType.AUTO) 
public Long getId() { 
    return id; 
} 

@SuppressWarnings("unused") 
private void setId(Long id) { 
    this.id = id; 
} 

@ManyToOne 
@JoinColumn(name = "reporter_fk") 
public Reporter getReporter() { 
    return reporter; 
} 

public void setReporter(Reporter reporter) { 
    this.reporter = reporter; 
} 

}

我想要的只是在獲取新聞時獲取報告的最高版本。我試圖詮釋報告文學：

@Loader(namedQuery = "fetchFinal") 
@NamedNativeQuery(name = "fetchFinal", query = "SELECT t.* FROM" + 
     "(SELECT id, subject, max(version) maxVersion, content, reporter" + 
     "FROM reportage GROUP BY id) x" + 
     "JOIN reportage t ON x.id = t.id AND x.maxVersion = t.version AND t.id = ?" 
) 

，但它不工作，他說：

初始SessionFactory的創建failed.org.hibernate.cfg.NotYetImplementedException：純天然的標量的查詢尚不支持

任何想法如何完成它？

Answer 1

如何：

select * from reportage t where t.version = (select max(t2.version) from reportage t2) 

UPDATE：

沒有嘗試這樣做我自己：

@NamedNativeQuery(name = "fetchFinal", query = "SELECT t.* FROM" + 
     "(SELECT id, subject, max(version) maxVersion, content, reporter" + 
     "FROM reportage GROUP BY id) x" + 
     "JOIN reportage t ON x.id = t.id AND x.maxVersion = t.version AND t.id = ?", 
     resultClass=Reportage.class) 

=添加Resultclass

UPDATE2

如果這不起作用，這當然會（因爲我自己做過）;使用標準：

Criteria crit = getSession().createCriteria(Reportage.class); 

DetachedCriteria dc = DetachedCriteria.forClass(Reportage.class); 
dc.setProjection(Projections.max("version")); 

crit.add(Property.forName("version").eq(dc)); 
return crit.list();