Relational algebra is a conceptually different approach to "merging data back together". So, I think the key point you made is that people end up optimizing the

Relational algebra is a conceptually different approach to "merging data back together". So, I think the key point you made is that people end up optimizing their data storage to support faster joins. Key/value stores have a different approach to "merging data back together". They seem more inclined to keep the data together in the first place (documents). Both require a language of some kind to do the merging. NoSql is like saying NoMapReduce or even more like NoAlgebra. I agree it is more like NoJoin.