c) If a client in transaction context A calls an entity object (the
logical object as seen by him), then the container delegates the call
to an entity bean instance (say, EJB-A). Until the transaction
commits, this instance is only(!) accessible wihtin the transaction
context A.
This means, that another client and/or another transaction context
calling this entity object will not(!) be delegated to EJB-A, but to
another entity bean instance EJB-B. EJB-A and EJB-B represent the same
logical entity object and both can be understood as being in-memory
copies (caches) of the same database
这段话的意思是不是说:一条数据库记录在内存中可能有两个缓寸数据?请指教,谢谢!