Java Hibernate 使用条件执行更新
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Hibernate execute update with criteria
提问by vlio20
Is it possible to execute an update while using Criteriain Hibernate? For example:
使用Criteriain 时是否可以执行更新Hibernate？例如：
Session session = getSession();
Criteria crit = session.createCriteria(User.class);
crit.add(Restrictions.eq("token", sessionToken));
User user= new User();
Transaction tx = session.getTransaction();
try
{
tx.begin();
session.updateWithCriteria(user, crit); //my imaginary function
tx.commit();
}
catch (Exception e)
{
e.printStackTrace();
tx.rollback();
}
session.close();
采纳答案by Radim K?hler
There is a very powerful feature called:
有一个非常强大的功能叫做：
15.4. DML-style operations
15.4. DML 风格的操作
small cite from doc:
来自 doc 的小引用：
... However, Hibernate provides methods for bulk SQL-style DML statement execution that is performed through the Hibernate Query Language...
... 但是，Hibernate 提供了通过 Hibernate 查询语言执行的批量 SQL 样式 DML 语句执行的方法...
So, while this is not about criteria- we still can use our domain model for querying, because it is about HQL. This is a snippet showing the power:
所以，虽然这不是关于criteria- 我们仍然可以使用我们的域模型进行查询，因为它是关于HQL 的。这是一个显示力量的片段：
Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();
String hqlUpdate = "update Customer c set c.name = :newName where c.name = :oldName";
// or String hqlUpdate = "update Customer set name = :newName where name = :oldName";
int updatedEntities = s.createQuery( hqlUpdate )
.setString( "newName", newName )
.setString( "oldName", oldName )
.executeUpdate();
tx.commit();
session.close();
SUMMARY: Having that in place:
总结：有了它：
- we can use query to filter results
- we can apply bulk update on it
- we won't need to load these rows in memory, into the session...
- 我们可以使用查询来过滤结果
- 我们可以对其应用批量更新
- 我们不需要将这些行加载到内存中，进入会话......
回答by ?smail Yavuz
First you should get the object then modify and update:
首先你应该得到对象然后修改和更新：
Query q = session.createQuery("from StockTransaction where tranId = :tranId ");
q.setParameter("tranId", 11);
StockTransaction stockTran = (StockTransaction)q.list().get(0);
stockTran.setVolume(4000000L);
session.update(stockTran);
If you want to use partial/dynamic update feature then put
如果你想使用部分/动态更新功能，那么把
@org.hibernate.annotations.Entity(
dynamicUpdate = true
)
annotation on top of the dao class.
dao 类顶部的注释。
Example from: http://www.mkyong.com/hibernate/hibernate-dynamic-update-attribute-example/
示例来自：http: //www.mkyong.com/hibernate/hibernate-dynamic-update-attribute-example/
Note: The Question is "with criteria" but the accepted answer is NOT "with criteria" but SQL.
注意：问题是“有条件”，但接受的答案不是“有条件”而是 SQL。
回答by Payal Bansal
Now we can do something like this for bulk update and delete. New api's released for criteriaUpdate and CriteriaDelete
现在我们可以为批量更新和删除做这样的事情。发布了用于标准更新和标准删除的新 api
CriteriaBuilder cb = this.em.getCriteriaBuilder();
// create update
CriteriaUpdate<Order> update = cb.createCriteriaUpdate(Order.class);
// set the root class
Root e = update.from(Order.class);
// set update and where clause
update.set("amount", newAmount);
update.where(cb.greaterThanOrEqualTo(e.get("amount"), oldAmount));
// perform update
this.em.createQuery(update).executeUpdate();
