From C to Q, One Event at a Time: Event Sourcing in Pictures

on YouTube ↗47m

" summary

Introduces Event Sourcing and CQRS as alternatives to traditional relational, transactional persistence for scalable and microservice architectures. Explains problems that arise when scaling and moving to distributed, asynchronous systems, then shows how Command Sourcing and separation of writes and reads (CQRS) address those issues and how to handle eventual consistency. Concludes with pros/cons and hard-won lessons from real projects, using simple sketches rather than a single implementation or DDD assumption.

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" chapters (31)

1. 0:00Introduction
2. 2:50The concept of aggregate
3. 4:48How a traditional application works
4. 5:49More requests are needed
5. 7:54The synchronous process is one of the worst enemies of scalability
6. 10:32Why don’t we save the commands?
7. 12:18How do I do it well?
8. 14:57The flow of commands
9. 15:57Validating commands
10. 17:11Long transactions
11. 19:09Compensating action
12. 20:46Corrective action
13. 22:07Free history
14. 23:07Our world is consistent at the business level
15. 24:59The system applies well to distributed systems
16. 26:07The component transforms commands into events
17. 29:12Thinking fast or slow?
18. 30:27How to answer questions?
19. 32:30Separation between commands and queries
20. 33:44Downstream database
21. 35:52Materialized views
22. 37:43Disadvantages
23. 39:20Evolution and adjustment
24. 40:09Event log
25. 41:35Event flow
26. 42:07Common mistakes
27. 43:01Normalized schema
28. 43:53Don’t get bogged down
29. 44:22Let’s sum it all up
30. 45:41Advantages
31. 46:29Conclusions

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