使用Entity entity = hibernateTemplate.get(Entity.class, id);when I hit a entity.getChild()which is a OneToOne relation,所有其他 OneToOne 關系也被加載。我使用休眠 5.4.1-Final。我使用字節碼增強如下:<configuration> <failOnError>true</failOnError> <enableLazyInitialization>true</enableLazyInitialization> <enableDirtyTracking>false</enableDirtyTracking> <enableAssociationManagement>true</enableAssociationManagement></configuration>A.java@Entity@Table(name = "A")public class A { @Id @Column(name = "ID_A") private String id; @OneToOne(fetch = FetchType.LAZY) @JoinColumn(name = "ID_A") @LazyToOne(LazyToOneOption.NO_PROXY) private B b; @OneToOne(fetch = FetchType.LAZY) @JoinColumn(name = "ID_A") @LazyToOne(LazyToOneOption.NO_PROXY) private C c;...getters/setters...B.java@Entity@Table(name = "B")public class B { @Id @Column(name = "ID_A") private String id;}C.java@Entity@Table(name = "C")public class C { @Id @Column(name = "ID_A") private String id;}所以當我做A a = hibernateTemplate.get(A.class, "100"); // triggers an Hibernate query only on A entity. The B and C aren't fetched => OK// Hibernate: select a0_.ID_A as ID_A_27_0_ from A a0_ where a0_.ID_A=?a.getB(); // ERROR : triggers two queries : one on C and one on B// Hibernate: select c0_.ID_A as ID_A _26_0_ from C c0_ where c0_.ID_A =?// Hibernate: select b0_.ID_A as ID_A _13_0_ from B b0_ where b0_.ID_A =?即使我獲取了B一個HQLQuery,我仍然有一個查詢C:Query<A> queryA = hibernateTemplate.createHQLQuery("from A a join fetch a.b where a.id=:id", A.class);queryA.setParameter("id", "100");A a = queryA.uniqueResult(); // triggers an inner join// Hibernate: select a0_.as ID_A1_27_0_, b1_.ID_A as ID_A1_13_1_ from A a0_ inner join B b1_ on a0_.ID_A=b1_.ID_A where a0_.ID_A=? a.getB(); // KO -> triggers a query to select C !// Hibernate: select c0_.ID_A as ID_A1_26_0_ from C c0_ where c0_.ID_A=?我嘗試進行雙映射(指定了 mappedBy 的 OneToOne)但沒有成功。B和C的PK和A一樣。我希望a.getB();不會觸發 C 的獲取。這是一個休眠錯誤嗎?我在他們的文檔中找不到有關此行為的任何信息。我的映射正確嗎?
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largeQ
TA貢獻2039條經驗 獲得超8個贊
它似乎按設計工作:) b 和 c 屬于相同的默認“LazyGroup”。如果需要加載 b 或 c 中的任何一個,則整個組都會加載。
引用字節碼增強器文檔:
惰性屬性可以指定一起加載,這稱為“惰性組”。默認情況下,所有單數屬性都是單個組的一部分,這意味著當訪問一個惰性單數屬性時,將加載所有惰性單數屬性。惰性復數屬性,默認情況下,每個屬性都是一個惰性組。此行為可通過 @org.hibernate.annotations.LazyGroup 注釋顯式控制。
@LazyGroup("b")
只需在 b 字段和 c 上添加,它應該按預期工作:b 將僅在, anc c on 上@LazyGroup("c")
加載。getB()
getC()
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