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CQRS: Write operation are not done in the same persistence storage than on the read operation.
When users interact with the information they use various presentations of this information.
Splitting the conceptual model into separate models for update and display.
CQRS fits well with event-based programming models (stream).
Having separate models raises questions about how hard to keep those models consistent, which raises the likelihood of using eventual consistency.
It applies the CQS principle by using separate Query and Command objects to retrieve and modify data, respectively