NoSQL databases have emerged as a response to some perceived problems in the RDBMSs: agile/dynamic schemas; and transparent, horizontal scaling of the database. The former has been promptly targeted with the introduction of unstructured data types, but scaling a relational databases is still a very hard problem.
As a consequence, all NoSQL databases have been built from scratch: their storage engines, replication techniques, journaling, ACID support (if any). They haven't leveraged the previously existing state-of-the-art of RDBMSs, effectively re-inventing the wheel. Isn't this sub-optimal? Wouldn't it be possible to construct a NoSQL database by layering it on top of a relational database?
Session presented at Big Data Spain 2015 Conference
16th Oct 2015
Event promoted by: http://www.paradigmatecnologico.com