"a relational data model on top top of hash-map" is my original idea, and then combine [The Pure Function Pipeline Data Flow v3.0 with Warehouse/Workshop Model](https://github.com/linpengcheng/PurefunctionPipelineDataflow), can perfectly realize the simplicity and unity combination of system architecture.
not the parent (but I like their thinking); I think the key concept is to treat the hash map as just a (potentially primary) index over your data. Of course keeping secondary indices up to date is now the job of the application (or the abstraction layer)
Are there any books that cover the concepts?