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Building Event-Driven Microservices - Chapter 7 - Stateful-Streaming
Event-Driven Microservices need to materialize states. And it comes with the important things to think about. Two approaches to choose from:
Internal state store or External state store Both have pros and cons. Both have important scalability and recovery considerations.
Two approaches for changing data structures:
Bebuilding and Migration Transactions and how to emulate them in order to implement Effectively Once processing.
All of these is disclosed in the Chapter 7 of the book we are currently studying: