migration from traditional CRUD app to Axon app

Imported from Google Groups
#1

I currently move my app code from traditional CRUD app to Axon，

now i face the situation to move the data from old app to Axon，there may be two part of work to do：

1：old data -> read store （mapping from traditional mysql tables）
2：old data -> event store

I wonder if i can only create SNAPSHOT event in event store and skip recreate domain events to simplify the job of migrate old data to event store?

#2

Hi,

creating a snapshot (and inserting it as a snapshot) is not recommended. Snapshots are a temporary replacements for other events, basically meaning they aren’t really part of the past. However, it is possible to create some sort of “SomethingImportedEvent” that contains data relevant for the first state of the aggregate. It’s not really a snapshot, just a big event describing initial state.

In some cases, it is possible to deduce some of the past of an aggregate from its current state. In that case, you could re-use existing events to build that state in the event store.

Cheers,

Allard