Hibernate 和 Ehcache - 如何确保每个“选择”都有效通过实体缓存？
我有一个实体（带有 Hibernate 查询接口的 JPA 注释），它具有两个属性的复合业务键（一个 external-id 和一个 subsidiary-id [这是一个外键] ]) 和主数据库键。
我有一个 JavaSE 多线程进程，它“相对于子公司”运行，并且需要使用该组合键查询/更新/插入这些实体（它获取这些 external-ids 的数据集）。
我可以保证，一旦这样的进程加载，其他进程将不会尝试插入/更新/删除该子公司。
我想要的是在启动时加载该子公司的所有现有实体，然后让每个查询对一对 [externalId,subsidiaryId] 进行缓存，并且仅当未命中时才进行缓存数据库。如果进程中的一个线程插入一个实体，我当然希望将其添加到该缓存中。
最好的做法是什么？
我知道有查询缓存，但据我所知，每 [externalId,subsidiaryId] 对的第一次仍然会错过。
谢谢，如果有任何不清楚的地方，请询问
更新
我不得不停止调查这个问题，但现在我又回到了这个问题，我认为只有查询缓存和 JB Nizet 的答案是唯一适用的似乎是合理的。
我会接受 JB Nizet 的回答，因为它很有趣，我可能会使用它（还不确定）。
I have an entity (JPA annotations with Hibernate query interface) which has a composite business key of two properties (an external-id and a subsidiary-id [that's a foreign key]) and a primary db key.
I have a JavaSE multi-threaded process which runs "with respect to a subsidiary" and needs to query/update/insert those entities using that composite key (it gets datasets of those external-ids).
I can guarantee that once such a process loads no other process will try to insert/update/remove that subsidiary.
What I want is to load all existing entities of that subsidiary on startup and then have every query for a pair of [externalId,subsidiaryId] to go through the cache and only if there's a miss to go through the db. In case one of the threads from the process inserts an entity I of course want that to be added to that cache.
What's the best course of action?
I know there's query caching but from what I can gather that will still be a miss the first time of every [externalId,subsidiaryId] pair.
Thanks and if there's anything which I'm not clear about please ask
Update
I had to stop investigating this issue but now that I've come back to it I think that it's seems reasonable that only the query cache and JB Nizet's answer are the only ones applicable.
I'll accept JB Nizet's answer as it is interesting and I might use it (not sure yet).
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我将为实体使用二级缓存，在启动时查询所有子公司的实体（这将填充二级缓存），并初始化一个仅映射
[externalId,subsidiaryId] 到 <代码>[id]。然后，每次搜索具有给定
[externalId,substitutionId]的实体时，首先从应用程序缓存中获取其 ID，然后I would use a second-level cache for the entity, query for all the subsidiry's entities at startup (this will fill the second-level cache), and initialize an application cache which would just map
[externalId, subsidiaryId]to[id].Then, each time you're searching for an entity with a given
[externalId, subsidiaryId], first get its ID from the application cache, then