CQRS Documents by Greg Young
Figure 17 An Event Stream
The problem that exists is that there may be a very large number of events between the beginning of time and the current point. It can be easily imagined that there is an event stream with a million or more events that have occurred, such an event stream would be quite inefficient to load. The solution is to use a Rolling Snapshot, to place a denormalization of the state at a given point in time. It would then be possible to only play the events from that point in time forward in order to load the Aggregate.
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