Manage data of service

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Data management
In Microservices

2. Data management in Microservices
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Data management
in Microservices

3. Data management in Microservices
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Monolithic
Application
DB

4. Data management in Microservices
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Microservices
Service 1 Service 2 Service 3

5. Data management in Microservices
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Microservices
Service 1 Service 2 Service 3
1. Shared database
DB

6. Data management in Microservices
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Microservices
Service 1 Service 2 Service 3
2. Database per service
DBDB DB

7. Data management in Microservices
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Database per service
High complexity
Query data across multiple databases
Challenge “How to join data ?”
Maintain database consistency

8. Data management in Microservices
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How to maintain data
consistency across services ?

9. Data management in Microservices
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We need …
Don’t need distributed transaction
Reduce complexity of code
Reliable

10. Data management in Microservices
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???
Service 1
Service 2
Service 3
Sequence of Tx and emit event or message
that trigger the next process in Tx
Event
produce
consume
Event
produce
consume
Timeline

11. Data management in Microservices
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???
Service 1
Service 2
Service 3
Sequence of Tx and emit event or message
that trigger the next process in Tx
1. command 2. response
3. command
4. response

12. Data management in Microservices
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Message vs Event
Message is addressed to someone
Event is something that happen and someone
can react to that

13. Data management in Microservices
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“Saga”

14. Data management in Microservices
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Event sourcing
Maintain source of truth of business
Immutable sequence of events
Event Event TimelineEventEvent Event
Sequence of event is keep in Event store

15. Data management in Microservices
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Event store
Keep events in order
Broadcast new event
Service 1 Service 2 Service 3
Event store
produce consume consume

16. Data management in Microservices
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With Event sourcing, we can
decouple services (query and
command)

17. Data management in Microservices
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CQRS
Command Query Responsibility Segregation

18. Data management in Microservices
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CQRS
Separate command and query services
Command Query
Event store
produce consume
DB

19. Data management in Microservices
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Event sourcing with database
Working with database
Bin log Event storeDB
bin log event
Binlog or Binary log event is information about data modification made to database
Event Event Event

20. Data management in Microservices
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Event sourcing
Duplication data (denormalize database)
Complexity (separate query and command)
Difficult to maintain

21. Data management in Microservices
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Event sourcing can’t solve all
problems

22. Data management in Microservices
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Start with understand your
purpose

23. Data management in Microservices
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Start with understand your
problem to resolve