Java JPA REQUIRES_NEW 事务何时提交
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When exactly does JPA REQUIRES_NEW transaction commit
提问by Ahmad Y. Saleh
In a spring container, with the code below:
在 spring 容器中，代码如下：
public class A {
@Transactional
public void m1() {
...
b.m2(); // call in a new transaction
...
}
}
public class B {
@Transactional(propagation = Propagation.REQUIRES_NEW)
public void m2() {
...
}
}
when exactly the transaction created for m2()is committed?once m2()invocation ends, or once m1()invocation ends?
何时m2()提交为其创建的事务？一旦m2()调用结束，或者一旦m1()调用结束？
When does @TransactionAttribute(TransactionAttributeType.REQUIRES_NEW) commit?answers it for EJB, but it doesn't seem to be the same behavior for JPA.
@TransactionAttribute(TransactionAttributeType.REQUIRES_NEW) 什么时候提交？为 EJB 回答它，但它似乎与 JPA 的行为不同。
I debugged it and I can only see the effect of m2()on DB after m1()ends, but that seems odd to me, am I missing something here?
我调试了它，我只能看到结束m2()后对 DB的影响m1()，但这对我来说似乎很奇怪，我在这里遗漏了什么吗？
UPDATE:
更新：
I was passing the entity I retrieved in m1()to m2()and updating it from there.
So, actually merging the entity in m2()solves this and Mik378answer is correct.
我正在传递我检索m1()到的实体m2()并从那里更新它。所以，实际上合并实体m2()解决了这个问题，Mik378 的答案是正确的。
采纳答案by Mik378
From here:
从这里：
Whether you're using the Spring Framework or EJB, use of the REQUIRES_NEW transaction attribute can have negative results and lead to corrupt and inconsistent data.
The REQUIRES_NEW transaction attribute always starts a new transaction when the method is started, whether or not an existing transaction is present.
无论您使用的是 Spring Framework 还是 EJB，使用 REQUIRES_NEW 事务属性都会产生负面结果并导致数据损坏和不一致。
REQUIRES_NEW 事务属性总是在方法启动时启动一个新事务，无论是否存在现有事务。
REQUIRES_NEWstarts a new transaction even if an existing transaction exist in the context.
REQUIRES_NEW即使上下文中存在现有事务，也会启动新事务。
So the short answer is: once m2()invocation ends
所以简短的回答是：一旦m2()调用结束
