JPQL更新查询的执行更新时事务必需的异常 [英] Transaction required exception on execute update for JPQL update query

问题描述

尝试运行此代码时出现此错误.

I get this error when I try to run this code.

错误:

javax.persistence.TransactionRequiredException:通过容器管理的事务性EntityManager的非事务访问获得的Query对象不支持executeUpdate

javax.persistence.TransactionRequiredException: executeUpdate is not supported for a Query object obtained through non-transactional access of a container-managed transactional EntityManager

代码:(_ ut是一个UserTransaction对象)

Code: (_ut is a UserTransaction object)

public void setMainCategory(Integer deptId，Integer catId){

public void setMainCategory(Integer deptId, Integer catId) {

        try {
            Query setmain = _entityManager.createNamedQuery("Category.setAsMain");
            Query removeMain = _entityManager.createNamedQuery("Category.removeMain");
            setmain.setParameter("categoryId", catId);
            Department d;
            d=_entityManager.find(Department.class, deptId);
            removeMain.setParameter("department", d);
            _ut.begin();
            removeMain.executeUpdate();
            _ut.commit();
            _ut.begin();
            setmain.executeUpdate();
            _ut.commit();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

我还有其他在实现上相同的功能，它们不会引发此错误.

I have other functions that are identical in implementation and they do not throw this error.

任何建议将不胜感激.

谢谢.

推荐答案

您正在使用EntityManager获取命名查询，并且还使用了(我认为是)注入的UserTransaction

You are using an EntityManager to get the Named Queries and also using an (what I think is) injected UserTransaction.

看到错误消息显示为"...通过非事务访问获得的查询对象..." .这意味着您将通过非事务访问获得"NamedQuery" ，因为EntityManager与_ut不在同一事务中.因此，首先将EntityManager加入UserTransaction，然后获取并执行查询.

See that the error message says "...Query object obtained through non-transactional access...". This means you are getting the "NamedQuery" through non-transactional access, because the EntityManager is not in the same transaction as _ut. So, you first join the EntityManager to the UserTransaction then you get and execute the query.

最后，您的区块应如下所示:

Finally your block should look like:

@PersistenceContext(unitName = "myPU")
EntityManager em;

@Inject
UserTransaction ut;

public void doSomeStuff()
{
    ut.begin();
    em.joinTransaction();

    em.createNamedQuery("query1").executeUpdate();

    ut.commit();
}

这篇关于JPQL更新查询的执行更新时事务必需的异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！