孤儿仍然在数据库中，即使orphanRemoval = true在一对多关系（JPA / Hibernate） [英] Orphans remain in database even with orphanRemoval=true on one-to-many relationship (JPA/Hibernate)
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问题描述
@Entity
@Inheritance（strategy = InheritanceType.SINGLE_TABLE）
@Table（name =company_policies）
@DiscriminatorColumn（name = rule_name）
public abstract class AbstractPolicyRule implements Serializable {
@Transient
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue
私人长ID;
私有字符串值;
...
}
_
@Entity
public class类实现Serializable {
@Transient
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue
私人长ID;
@Column（name =category_name）
私人字符串名称;
@OneToMany（fetch = FetchType.EAGER，cascade = {CascadeType.ALL}，orphanRemoval = true）
@JoinColumn（name =category_policy_id，referencedColumnName =id）
private Set< AbstractPolicyRule> activePolicyRules;
...
}
现有的activePolicyRules将其category_policy_id在数据库中设置为null，并插入新的。我想要将原始的删除。
我认为加入orphanRemoval = true会做到这一点，但事实并非如此。我在其中看到的其他问题似乎具有双向关系，并将父级设置为null可解决此问题，但这不是双向关系。
任何建议？
使用Hibernate 3.5.3
编辑：
只有当现有的AbstractPolicyRule存在于数据库中，我从列表中删除它，然后再次保存类别。
[DEBUG]找到的集合：[domain.category。 Category.activePolicyRules＃1]是：
[< unreferenced>]（初始化）
[DEBUG]刷新：0插入，2更新，0删除2个对象
[DEBUG]刷新：1个（重新创建），0个更新，1个删除到1个集合
...
[DEBUG]删除集合：[domain.category.Category2.activePolicyRules＃1]
[DEBUG]即将打开PreparedStatement（打开PreparedStatements：0，全局为0）
[DEBUG] update company_policies set category_policy_id = null where category_policy_id =？
[DEBUG]完成删除集合
还尝试了一个连接表，因为Hibernate文档不鼓励以前的方式：
@Entity
public class类实现Serializable {
@Transient
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue
私人长ID;
@Column（name =category_name）
私人字符串名称;
@OneToMany（fetch = FetchType.EAGER，cascade = {CascadeType.ALL}，orphanRemoval = true）
@JoinTable（name =policy_rule_mapping，
joinColumns = @JoinColumn （name =category_id），
inverseJoinColumns = @JoinColumn（name =rule_id））
private Set< AbstractPolicyRule> activePolicyRules;
...
}
这有同样的问题。映射表中的行将被删除，但AbstractPolicyRule仍包含已删除的项目。
解决方案
c> orphanRemoval = true 与一个单向一对多关联没有任何问题。
实际上，我测试了您的代码和以下内容方案（ AbstractPolicyRule 正确地）执行等于 / hashCode / p>
Category category = new Category（）;
AbstractPolicyRule policyRule1 = new AbstractPolicyRule（foo）;
category.addToActivePolicyRules（policyRule1）;
em.persist（category）;
em.flush（）;
assertNotNull（category.getId（））;
assertNotNull（category.getActivePolicyRules（））;
assertEquals（1，category.getActivePolicyRules（）。size（））;
category.removeFromActivePolicyRules（policyRule1）;
category.addToActivePolicyRules（new AbstractPolicyRule（bar））;
// category = em.merge（category）; //可以使用或不使用
em.flush（）;
assertEquals（1，category.getActivePolicyRules（）。size（））;
正常工作。在生成的跟踪下面：
22：54：30.817 [main] DEBUG org.hibernate.SQL - 插入类别（id，category_name）值（空，？）
Hibernate：插入类（id，category_name）值（空，？）
22：54：30.824 [main] TRACE org.hibernate.type.StringType - 参数：1
22：54：30.844 [main] DEBUG ohid.IdentifierGeneratorHelper - 本地生成的标识：1
...
22：54：30.872 [main] DEBUG org.hibernate。 SQL插入AbstractPolicyRule（id，name）values（null，？）
Hibernate：插入AbstractPolicyRule（id，name）values（null，？）
22：54：30.873 [main] TRACE org .hibernate.type.StringType - 将'foo'绑定到参数：1
22：54：30.874 [main] DEBUG ohid.IdentifierGeneratorHelper - 本地生成的标识：1
...
22 ：54：30.924 [main] DEBUG org.hibernate.SQL - update AbstractPolicyRule set category_policy_id =？其中id =？
Hibernate：更新AbstractPolicyRule set category_policy_id =？其中id =？
22：54：30.927 [main] TRACE org.hibernate.type.LongType - 绑定'1'参数：1
22：54：30.928 [main] TRACE org.hibernate.type.LongType - 绑定'1'到参数：2
22：54：30.929 [main] DEBUG ohpcAbstractCollectionPersister - 完成插入集合：插入1行
22：54：30.929 [main] DEBUG org.hibernate.jdbc。 AbstractBatcher - 执行批量大小：1
...
22：54：30.945 [main] DEBUG org.hibernate.SQL - 插入AbstractPolicyRule（id，name）values（null，？）
Hibernate：插入到AbstractPolicyRule（id，name）values（null，？）
22：54：30.948 [main] TRACE org.hibernate.type.StringType - 绑定bar到参数：1
22：54：30.948 [main] DEBUG org.hibernate.SQL - 更新AbstractPolicyRule set category_policy_id =更新AbstractPolicyRule set_type_policy_id = null where category_policy_id =？和id =？
Hibernate：update AbstractPolicyRule set category_policy_id = null where category_policy_id =？和id =？
22：54：30.991 [main] TRACE org.hibernate.type.LongType - 将参数绑定为'1'：1
22：54：30.992 [main] TRACE org.hibernate.type.LongType - 绑定'1'参数：2
22：54：30.993 [main] DEBUG ohpcAbstractCollectionPersister - 完成删除集合行：1删除
22：54：30.993 [main] DEBUG ohpcAbstractCollectionPersister - 插入集合：[com.stackoverflow.q3304092.Category.activePolicyRules＃1]
22：54：30.994 [main] DEBUG org.hibernate.jdbc.AbstractBatcher - 执行批处理大小：1
...
22：54：30.996 [main] DEBUG org.hibernate.SQL - update AbstractPolicyRule set category_policy_id =？其中id =？
Hibernate：更新AbstractPolicyRule set category_policy_id =？其中id =？
22：54：30.997 [main] TRACE org.hibernate.type.LongType - 绑定参数为'1'：1
22：54：30.998 [main] TRACE org.hibernate.type.LongType - 绑定'2'到参数：2
22：54：31.002 [main] DEBUG ohpcAbstractCollectionPersister - 完成插入行：1插入
...
22：54：31.015 [main] DEBUG org.hibernate.SQL - 从AbstractPolicyRule中删除，其中id =？
Hibernate：从AbstractPolicyRule中删除，其中id =？
22：54：31.017 [main] TRACE org.hibernate.type.LongType - 将参数绑定为'1'：1
第一条政策规则被删除。
如果这并不代表您在做什么，那么您应该提供更多代码。
更新：回答OP的评论...
哇将saveOrUpdate调用更改为合并，现在它正在适当地删除。你有什么洞察力，为什么这是？
只是一个猜测：因为 orphanRemoval 是一个JPA的东西，我不知道是否 saveOrUpdate 会适当地处理它（实际上，我以为你使用 EntityManager API，因为你提到过JPA）。
@Entity
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@Table(name = "company_policies")
@DiscriminatorColumn(name = "rule_name")
public abstract class AbstractPolicyRule implements Serializable {
@Transient
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue
private Long id;
private String value;
...
}
_
@Entity
public class Category implements Serializable {
@Transient
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue
private Long id;
@Column(name = "category_name")
private String name;
@OneToMany(fetch = FetchType.EAGER, cascade = { CascadeType.ALL }, orphanRemoval = true)
@JoinColumn(name = "category_policy_id", referencedColumnName = "id")
private Set<AbstractPolicyRule> activePolicyRules;
...
}
When this Set is updated the existing activePolicyRules have their category_policy_id set to null in the database and new ones are inserted. I'd like for the original ones to be deleted.
I thought adding the orphanRemoval = true would do that but it's not. Other questions I've seen on this appear to have bi-directional relationships and setting the parent to null solves it, but this is not a bi-directional relationship.
Any suggestions?
Using Hibernate 3.5.3
Edit: This only happens when an existing AbstractPolicyRule exists in the database, I remove it from the list and then save the Category again. It's foreign key, category_policy_id, is set to null instead of being deleted.
[DEBUG] Collection found: [domain.category.Category.activePolicyRules#1], was:
[<unreferenced>] (initialized)
[DEBUG] Flushed: 0 insertions, 2 updates, 0 deletions to 2 objects
[DEBUG] Flushed: 1 (re)creations, 0 updates, 1 removals to 1 collections
...
[DEBUG] Deleting collection: [domain.category.Category2.activePolicyRules#1]
[DEBUG] about to open PreparedStatement (open PreparedStatements: 0, globally: 0)
[DEBUG] update company_policies set category_policy_id=null where category_policy_id=?
[DEBUG] done deleting collection
Also tried a join table since the Hibernate documentation discourages the previous way:
@Entity
public class Category implements Serializable {
@Transient
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue
private Long id;
@Column(name = "category_name")
private String name;
@OneToMany(fetch = FetchType.EAGER, cascade = { CascadeType.ALL }, orphanRemoval = true)
@JoinTable(name = "policy_rule_mapping",
joinColumns = @JoinColumn(name = "category_id"),
inverseJoinColumns = @JoinColumn(name = "rule_id"))
private Set<AbstractPolicyRule> activePolicyRules;
...
}
This has the same issue. The row in the mapping table is deleted but the AbstractPolicyRule still contains the removed item.
解决方案
I'm using orphanRemoval=true with an unidirectional One-to-Many association without any problem.
And actually, I tested your code and the following scenario (AbstractPolicyRule implementing equals/hashCode correctly):
Category category = new Category();
AbstractPolicyRule policyRule1 = new AbstractPolicyRule("foo");
category.addToActivePolicyRules(policyRule1);
em.persist(category);
em.flush();
assertNotNull(category.getId());
assertNotNull(category.getActivePolicyRules());
assertEquals(1, category.getActivePolicyRules().size());
category.removeFromActivePolicyRules(policyRule1);
category.addToActivePolicyRules(new AbstractPolicyRule("bar"));
// category = em.merge(category); // works with or without
em.flush();
assertEquals(1, category.getActivePolicyRules().size());
just works as expected. Below the generated traces:
22:54:30.817 [main] DEBUG org.hibernate.SQL - insert into Category (id, category_name) values (null, ?) Hibernate: insert into Category (id, category_name) values (null, ?) 22:54:30.824 [main] TRACE org.hibernate.type.StringType - binding null to parameter: 1 22:54:30.844 [main] DEBUG o.h.id.IdentifierGeneratorHelper - Natively generated identity: 1 ... 22:54:30.872 [main] DEBUG org.hibernate.SQL - insert into AbstractPolicyRule (id, name) values (null, ?) Hibernate: insert into AbstractPolicyRule (id, name) values (null, ?) 22:54:30.873 [main] TRACE org.hibernate.type.StringType - binding 'foo' to parameter: 1 22:54:30.874 [main] DEBUG o.h.id.IdentifierGeneratorHelper - Natively generated identity: 1 ... 22:54:30.924 [main] DEBUG org.hibernate.SQL - update AbstractPolicyRule set category_policy_id=? where id=? Hibernate: update AbstractPolicyRule set category_policy_id=? where id=? 22:54:30.927 [main] TRACE org.hibernate.type.LongType - binding '1' to parameter: 1 22:54:30.928 [main] TRACE org.hibernate.type.LongType - binding '1' to parameter: 2 22:54:30.929 [main] DEBUG o.h.p.c.AbstractCollectionPersister - done inserting collection: 1 rows inserted 22:54:30.929 [main] DEBUG org.hibernate.jdbc.AbstractBatcher - Executing batch size: 1 ... 22:54:30.945 [main] DEBUG org.hibernate.SQL - insert into AbstractPolicyRule (id, name) values (null, ?) Hibernate: insert into AbstractPolicyRule (id, name) values (null, ?) 22:54:30.948 [main] TRACE org.hibernate.type.StringType - binding 'bar' to parameter: 1 22:54:30.948 [main] DEBUG o.h.id.IdentifierGeneratorHelper - Natively generated identity: 2 ... 22:54:30.990 [main] DEBUG org.hibernate.SQL - update AbstractPolicyRule set category_policy_id=null where category_policy_id=? and id=? Hibernate: update AbstractPolicyRule set category_policy_id=null where category_policy_id=? and id=? 22:54:30.991 [main] TRACE org.hibernate.type.LongType - binding '1' to parameter: 1 22:54:30.992 [main] TRACE org.hibernate.type.LongType - binding '1' to parameter: 2 22:54:30.993 [main] DEBUG o.h.p.c.AbstractCollectionPersister - done deleting collection rows: 1 deleted 22:54:30.993 [main] DEBUG o.h.p.c.AbstractCollectionPersister - Inserting rows of collection: [com.stackoverflow.q3304092.Category.activePolicyRules#1] 22:54:30.994 [main] DEBUG org.hibernate.jdbc.AbstractBatcher - Executing batch size: 1 ... 22:54:30.996 [main] DEBUG org.hibernate.SQL - update AbstractPolicyRule set category_policy_id=? where id=? Hibernate: update AbstractPolicyRule set category_policy_id=? where id=? 22:54:30.997 [main] TRACE org.hibernate.type.LongType - binding '1' to parameter: 1 22:54:30.998 [main] TRACE org.hibernate.type.LongType - binding '2' to parameter: 2 22:54:31.002 [main] DEBUG o.h.p.c.AbstractCollectionPersister - done inserting rows: 1 inserted ... 22:54:31.015 [main] DEBUG org.hibernate.SQL - delete from AbstractPolicyRule where id=? Hibernate: delete from AbstractPolicyRule where id=? 22:54:31.017 [main] TRACE org.hibernate.type.LongType - binding '1' to parameter: 1
The first policy rule gets deleted.
If this is not representative of what you're doing, you should maybe provide more code.
Update: Answering a comment from the OP...
Wow I just changed the saveOrUpdate call to merge and now it's removing appropriately. You have any insight why that is?
Just a guess: since orphanRemoval is a JPA thing, I wonder if saveOrUpdate will deal appropriately with it (actually, I thought you were using the EntityManager API since you mentioned JPA).
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