[speedgoose]

There is some truth in this tweet but it doesn't mean you should use a nosql document database.

Storing more context in document helps obviously because you don't have to fetch the data many times, it's actually also done in relational databases whenever needed. But you can't store a lot in one document, that doesn't scale nor work.

For example, if someone changes its avatar or want to delete its account, do you want to parse all your social network documents to update an avatar or remove the comments on a tiny subset of them ? If a post is popular, are you going to update its document thousands of times per second ?

In practice you will most likely find a mix of everything. Relational databases, in memory data stores, cache layers, perhaps a few nosql documents database, some big data stuff and a probably some excel sheets.

[databrecht]

Exactly! That's how I've built until now, a mix of databases. But it's also harder to manage. Database vendors notice this and that results in databases that start offering alternative ways of modeling.