Lately, it's looking more and more like the idea that SQL is fundamentally limited compared to NoSQL is waning - Lieven Doclo, Lukas Eder, and Matt Butcher are giving that impression, just to name a few - and that may be the case even when it comes to truly big data. According to Richard Chirgwin at The Register, the ISO SQL working group has announced a SQL/MDA spec project.
This would make SQL a bit more flexible when it comes to the complexity and scale of many modern multi-dimensional datasets - data from massive sensor networks, for example - which are currently often processed by other tools outside of relational databases:
The people behind SQL have decided it's time to get serious (really, really serious) about big (as in really, really big) multidimensional datasets, and have kicked off an effort to extend the standard, adding the new capabilities needed by spatial, scientific, engineering and medical users.
Chirgwin also points to a project called Rasdaman, which is working toward similar goals: a scalable multi-dimensional array analytics server and a SQL-like query language, to be precise. That, too, is making some progress:
Rasdaman, [GIM International notes], has showed impressive results: “In a recent technology demonstration, more than 1,000 computers collaborated in a cloud to jointly compute the result of a single database query. This ‘distributed query processing’ means a massive speed increase, and research challenges on multi-Petabyte data cubes can be answered that were previously unsolvable,” the outlet writes.
So, watch out, NoSQL. It sounds like the "cons" list for SQL is getting shorter and shorter.