[nosql] NoSQL Use Case Scenarios or WHEN to use NoSQL

With all the hype it seems really hard to find reliable information on when to use this. So I pose the following questions, and I'm sorry if these are really dumb questions in advance:

  1. Should I use NoSQL for user data? E.g. profiles, usernames + passwords, etc.
  2. Should I use NoSQL for important content? E.g. articles, blog posts, product inventory, etc.

I'm assuming no? And I feel like NoSQL is just for quickly accessible things from which it's OK to lose data. But I also read that NoSQL apps have built-in redundancy so that I don't lose data?

Also if the above 2 examples are bad, could you give me specific business use cases where I would use NoSQL? I see a lot of general descriptions but not a lot of real-world examples. The only things I can think of are user-to-user messaging and analytics.

Thanks!

This question is related to nosql use-case

The answer is


I think Nosql is "more suitable" in these scenarios at least (more supplementary is welcome)

  1. Easy to scale horizontally by just adding more nodes.

  2. Query on large data set

    Imagine tons of tweets posted on twitter every day. In RDMS, there could be tables with millions (or billions?) of rows, and you don't want to do query on those tables directly, not even mentioning, most of time, table joins are also needed for complex queries.

  3. Disk I/O bottleneck

    If a website needs to send results to different users based on users' real-time info, we are probably talking about tens or hundreds of thousands of SQL read/write requests per second. Then disk i/o will be a serious bottleneck.