[threeseed]

NoSQL != Schemaless.

That mantra hasn't been true for a number of years now. Especially since the big trend has been exposing SQL layers in front of NoSQL databases. For example Phoenix in front of HBase.

And SQL as well as all know requires data types to be usable.

[aidos]

Just to explain - I was going to write mongo originally but then decided to go more general. I evidentially went too general with my terminology. I've used mongo since the early days and I've also worked on projects that have used everything from neo4j and redis to oracle as the primary data store.

There are a bunch of things that made me nervous about mongo as the primary db. Data consistency was the main one and, like the author of the post - migrating away from mongo was hard almost entirely because of data inconsistency that had developed over the course of a couple of years.

Querying was also harder on an ad-hoc basis. With a relational db there are generally just a couple of recommended ways of modelling your data. But once you do that, it's easy to query after the fact. Or to add new stuff. With mongo I felt like I was constantly making a trade off that I would have to accept at querying time.