blocks|key|1133468|text|另一个示例是在"created_on“列上，您希望让数据库处理日期创建|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1133469|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

An other example would be on the "created_on" column where you want to let the database handle the date creation

blocks|key|918913|text|另一个原因可能是您的属性映射到视图的列(例如，您的hibernate实体是表和视图的融合)。因此，您的列不能被插入(也不能被更新)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|918914|@Entity
@Table(name+=+"THE_VIEW")
@SecondaryTable(name+=+"THE_TABLE",+pkJoinColumns+=+@PrimaryKeyJoinColumn(name+=+"THE_ID"))
public+class+MyEntity+{

++++@Id
++++@Column(name+=+"THE_ID")
++++private+Integer+id;

++++@Column(name+=+"VIEW_COLUMN",+updatable+=+false,+insertable+=+false)
++++private+String+viewColumn

++++@Column(name+=+"TABLE_COLUMN",+table+=+"THE_TABLE")
++++private+String+tableColumn;|code-block|syntax|javascript|918915|(我不在这里讨论可更新的视图)|918916|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Another reason could be that your attribute is mapper to a column of a view (Example, your hibernate entity is the fusion of a table and a view). So it does not make sens that your column can be inserted (nor updated).
<pre><code>@Entity
@Table(name = &quot;THE_VIEW&quot;)
@SecondaryTable(name = &quot;THE_TABLE&quot;, pkJoinColumns = @PrimaryKeyJoinColumn(name = &quot;THE_ID&quot;))
public class MyEntity {

 @Id
 @Column(name = &quot;THE_ID&quot;)
 private Integer id;

 @Column(name = &quot;VIEW_COLUMN&quot;, updatable = false, insertable = false)
 private String viewColumn

 @Column(name = &quot;TABLE_COLUMN&quot;, table = &quot;THE_TABLE&quot;)
 private String tableColumn;
</code></pre>
(I don't talk about updatable views here)

blocks|key|918985|text|除了前面的回答之外，insertable=false,+updatable=false的一个常见用途是保存冗余的数据库查询，从而提高性能。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|918986|想象一下，有一个Client类，它有一个父实体。如果您只想检查客户端是否有父级，则只需检查其parent_id列中是否存在值。不需要要求Hibernate获取父实体，可能还有它的所有其他关联，这会导致额外数量的查询：|918987|public+class+Client+{
++++@ManyToOne(cascade+=+{CascadeType.MERGE,+CascadeType.PERSIST},+fetch+=+FetchType.LAZY)
++++@JoinColumn(name+=+"parent_id")
++++private+Parent+parent;

++++@Column(name+=+"parent_id",+insertable+=+false,+updatable+=+false)
++++private+UUID+parentId;
}|code-block|syntax|javascript|918988|通过上面的设置，parentId字段将简单地获取存储在parent_id列中的任何值，该列仅由父实体编辑/更新。|918989|entityMap^0|A|X|0|1A|9|0|0|8|8|R|9|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@$9|U|A|V|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|W|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|X|8|@$9|Y|A|Z|B|C]|$9|10|A|11|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|12|8|@]|D|@]|E|$]]]|P|$]]

Adding to the previous answers, a common use of <code>insertable=false, updatable=false</code> is to save redundant database queries, thereby improving performance.
Imagine having a Client class, which has a Parent entity. If you just want to check if a Client has a Parent, you simply need to check for the presence of value in its <code>parent_id</code> column. There is no need to ask Hibernate to fetch the Parent entity, with possibly all of its other associations, leading to additional number of queries:
<pre><code>public class Client {
 @ManyToOne(cascade = {CascadeType.MERGE, CascadeType.PERSIST}, fetch = FetchType.LAZY)
 @JoinColumn(name = &quot;parent_id&quot;)
 private Parent parent;

 @Column(name = &quot;parent_id&quot;, insertable = false, updatable = false)
 private UUID parentId;
}
</code></pre>
With the setup above, the <code>parentId</code> field will simply fetch whatever value is stored in the <code>parent_id</code> column, which is solely edited/updated by the Parent entity.

blocks|key|919023|text|我认为这仅仅意味着：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|919024|列是否包含在持久性提供程序生成的SQL+INSERT语句中。|919025|参考：https://www.objectdb.com/api/java/jpa/Column|offset|length|919026|entityMap|0|LINK|mutability|MUTABLE|url|https://www.objectdb.com/api/java/jpa/Column^0|0|0|3|18|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@$F|S|G|T|1|U]]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

I think it simply mean :
Whether the column is included in SQL INSERT statements generated by the persistence provider.
Reference: <a href="https://www.objectdb.com/api/java/jpa/Column" rel="nofollow noreferrer">https://www.objectdb.com/api/java/jpa/Column</a>

If a field is annotated <code>insertable=false, updatable=false</code>, doesn't it mean that you cannot insert value nor change the existing value? Why would you want to do that?

<pre><code>@Entity
public class Person {

 @Id
 @GeneratedValue(strategy = GenerationType.AUTO)
 private Long id;

 @OneToMany(mappedBy="person", cascade=CascadeType.ALL)
 private List&lt;Address&gt; addresses;
}

@Entity
public class Address {

 @Id
 @GeneratedValue(strategy = GenerationType.AUTO)
 private Long id;

 @ManyToOne
 @JoinColumn(name="ADDRESS_FK")
 @Column(insertable=false, updatable=false)
 private Person person;
}
</code></pre>

Please explain about insertable=false and updatable=false in reference to the JPA @Column annotation

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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如果一个字段被注释为insertable=false, updatable=false，这不是意味着您不能插入值或更改现有值吗？你为什么要这么做呢？@Entitypublic class Person {    @Id    @GeneratedValue(strategy = GenerationType.AUTO)...

问请参考JPA @Column注解解释一下insertable=false和updatable=false
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问请参考JPA @Column注解解释一下insertable=false和updatable=falseEN

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问请参考JPA @Column注解解释一下insertable=false和updatable=false
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