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you just described wal files of a database.

The generalized architecture is called event sourcing

Well, I'd argue that it's just two different names for similar concepts, but applied at different levels. WAL is a low-level implementation detail, usually for durability, while Event Source is a architecture applied to solve business problems.

A WAL would usually disappear or truncate it's length after a while, and you'd only rerun things from it if you absolutely have two. Changes in business requirements shouldn't require you to do anything with a WAL.

In contrast, Event sourcing log would be kept indefinitely, so when business requirements change, you could (if you want to, not required) re-run N previous events so you can apply new changes to old data in your data storage.

But, if you really want to, it's basically the same, but in the end, applied differently :)

WAL is just one moving piece of database, that could be using SSTable or LSM tree or some other append-only immutable data structure, and the Event Sourcing is enterprise architecture pattern applied to business applications that heavily relies on immutable append-only data structures as the backbone

ha I was just thinking how similar this was to postgres pg-audit way of reusing the logs to sum up the correct state

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