Mongodb 更改流获取以前的值？

Question

Recently I learned about change streams in mongodb and how powerful they are, but I'm in need of getting the previous values before an update. However, I seem to have learned through some research that it's impossible to get the previous values? So this got me thinking about what alternatives exist in order to retrieve those previous values?

What I want to achieve is a logging system such as, “Record A field has changed from {old_value} to {new_value}.” I'm using socket.io to push these updates to a react front-end client. The updates to records would be happening from a completely different system and not on the same blackened server where the change streams would be listening so I won't be able to query the document before updating.

So I started to think of a different solution…maybe I could have two databases? One contains the old records and the other the updated records but this sounds like a duplication of data. And I can't imagine having thousands of records.

I need some guidance as I really don't know what the best option is? Is there really no way you can use change streams and get the previous values? Is it possible to somehow query the document before a change stream event? Thank you.

Answer 1

不知道我是怎么错过的，但解决方案是对数据进行版本控制。