Event Sourcing

This is a system design pattern where any state changes are written as history of events and this history is the single source of truth.

How this is used?

• All other systems use this to trigger other tasks.
• The event history is then represented in different ways using projections.

How projections are used?

For example, the event data is used to build a view which shows just the final state of an object.

different from CDC

In case of CDC, the final state is written to database and the database log is used to trigger other processes.

Whereas in case of event sourcing, only the history is the single source of truth. All events and states are triggered from it.