asya999

I think Mark meant to link to

https://docs.mongodb.com/manual/reference/operator/aggregation/lookup/

(as did the datalake docs page - bug report filed).

Your comments/complaints are 100% valid - as Mark said, we need to do better. Sometimes fast growth (of product, of company) means not every function manages to keep up - we are committed to doing better, and MongoDB University is *not* going away and hopefully will get better (again) soon.

> Graduated Harvard 2019...so 23ish?

Right, and that means he was -10 when he graduated from CalTech!

Operationally, I don't know of any relational databases that were built with replication and sharding as first class parts of the cluster architecture, in my experience they were always bolted on after the fact, and usually for a whole lot of extra $$$.

As far as object in code mapping directly to documents in the database, I suppose there were object databases for a while (a bit before their time) but relational databases certain don't support it - you have to add an extra layer to map your objects to tables which is where a lot of disconnect happens and performance issues creep in.

This is probably not the best venue for these questions (https://community.mongodb.com probably is the right place) but I can tell you right off that since you want to replace already existing documents, you should probably use update operation with upsert option, rather than insert operation.