Yes, it should work, but I need to know how to write the code :) Willem Jiang
Twitter: willemjiang Weibo: 姜宁willem On Mon, Sep 10, 2018 at 2:01 PM 赵俊 <zhaoju...@jd.com> wrote: > > It seems that adding a version field in product entity will work. > > > On 10 Sep 2018, at 11:43 AM, Willem Jiang <willem.ji...@gmail.com> wrote: > > > > Hi， > > > > I submitted a PR[1] to show how to use TCC with JPA. There are some > > missing points with my limited knowledge of JPA. So I just send out > > this email to ask help from community. > > > > In the inventory service[2], we need to update the product in stock > > number[3]. As the reserver method could be invoked in multiple > > threads at the same time and JPA doesn't provide the isolation across > > these thread[4]. We may need to add optimis lock or use version to > > keep track for the change. But I didn't manage to get workable code > > by applying the optimic lock or using the version file to prevent the > > lost updates[5]. > > > > So I'm asking help from the expert of JPA for an example of this case. > > > > [1]https://github.com/apache/incubator-servicecomb-saga/pull/290 > > [2]https://github.com/apache/incubator-servicecomb-saga/tree/SCB-820/saga-demo/tcc-spring-demo/inventory > > [3]https://github.com/apache/incubator-servicecomb-saga/blob/SCB-820/saga-demo/tcc-spring-demo/inventory/src/main/java/org/apache/servicecomb/saga/demo/pack/inventory/InventoryService.java#L44 > > [4]https://vladmihalcea.com/a-beginners-guide-to-database-locking-and-the-lost-update-phenomena/ > > [5]https://vladmihalcea.com/preventing-lost-updates-in-long-conversations/ > > > > > > Willem Jiang > > > > Twitter: willemjiang > > Weibo: 姜宁willem >
