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讓說我有2個表由一個一對多的關係是否可以使用外鍵值在JPA2中創建條件查詢?
public class Slave
{
@Id
@Column(name = "id")
long id;
@JoinColumn(name = "master", referencedColumnName = "id")
Master master;
}
public class Master
{
@Id
@Column(name = "id")
long id;
@OneToMany(mappedBy = "master", targetEntity = Slave.class)
Collection<Slave> slaves;
}
加入了是否有可能創造CriteriaQuery中選擇法師所有的奴隸與已知的ID? 生成SQL這樣的:
SELECT * FROM slave s WHERE s.master=XXX;
應該CriteriaQuery
不僅僅是 「本地查詢」 像這樣
_entityManager.createNativeQuery("SELECT s FROM master s WHERE s.master = ?1");
query.setParameter(1, XXX);
預先感謝您
剛一說明創建CriteriaQuery中,如果你改變'master'的財產,'masterId'不immediatelly改變,你需要堅持實體並從EntityManager中刷新它... – mirec 2014-10-04 11:41:08