But it doesn’t help with relationships between data. I plan to dig a bit more and play around with that over the next few weeks.
Here is a simple example of the difference between SQL and a Document Store. Take your example with Actor/Actress example. Betty White, movies she was in. What if you also afterwards want to add was the movie made into a comic book, if made into a comic book was there a sequel? If a sequel did the sequel make more than the original? Was there a sequel to the sequel? Was there a remake of the entire series 10 years later or more? Did the actor or actress ever appear in Game of Thrones? If so, which episode(s), on which dates, with what ratings (to try to evaluate the true monetary value that the actor/actress incrementally brings to the show)…let me know how you would do all this in an SQL that already has its scheme set up and do it on the fly, at scale, with terabyte horizontal scaling on commodity servers.
Or something simple like adding her phone number. Oh wait, now phone numbers also need area codes (when I was younger phone numbers were 7 numbers unless you were going to make a long-distance call). Even if you had area codes to start with what if we then have to add in international codes (or perhaps and 11th or 12th number for region if 10 digit numbers become exhausted) but the schema only holds 7 digits or only holds 10 digits?
What if area code 678 (as used in Avengers) is changed to 412 at some point in time.
Each time in an SQL you have to change the schema, you may have to add new tables, it suddenly becomes more and more complicated and more and more convoluted and less and less manageable requiring more and more expensive DBAs to manage it all, and less and less ability to to be flexible with your scheme.
In a document database you can handle all those changes without a single change to schema.
Further, what is your date is unstructured to begin with, such as collecting data from social media…good luck with the SQL.
That is why NoSQL is starting to go mainstream. That is why Cisco uses MongoDB as its front end commerce website. That is why Fortnite runs on top of Mongo and not on top of Oracle.
Just a few examples. Also, traditional DBAs are going to be cynical about it just like laproscopic surgeons were about DaVinci.
Tinker