[Daishiman]

The problem is that without a table lock of some sort you cannot guarantee that all the documents in a store satisfy the schema definition.

The NoSQL solution is basically say, "assume that nothing could ever possibly respect any semblance of a schema and build special cases around everything". It is a very unproductive way of thinking, taking defensive programming to the extreme.

Also, joins will be a necessity for all sorts of data querying. At the end of the day, schemas are a necessity for 98% of all work, whether defined through types or ad-hoc.