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Comment by neilk | Hacker News Reader

I find it a bit disturbing how this post reaches the top of HN. But I suppose I shouldn't be surprised.

I probably live in my own little bubble, but only lately have I realized that NoSQL has two audiences: (1) People for whom normalization can't work because of their application's characteristics and the limitations of current hardware. (2) People who just don't understand basic relational concepts, or why they were invented in the first place.

It's kinda sad. I've consulted on projects where people implemented sharding before adding any indices to MySQL.

The thing about being in group (1) is that you can also recognize when the ground shifts beneath your feet. Artur Bergman is one of those guys.

http://www.youtube.com/watch?v=H7PJ1oeEyGg&feature=youtu...

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There's a group 3, but it's likely just as small or smaller than group 1. Where your data is easily normalized (and easier to work with in that form), but the cost of a getting an rdbms to support your write load is an order of magnitude more expensive than a persistent 'nosql' datastore that you do batch dumps into an rdbms.

The catch is that very few people end up in group 3 and still have the cost of running/administering the rdbms over the 'nosql' one actually matter.

The point in NoSQL is mostly in group (3), web2+ startups with a possible 1B user and 1000B things (comments etc) per user. Joins and normalization here are a bit costlier and what is written in your Oracle development manuals, for your small workgroup intracompany app don't work here.

So the group (0), which are mostly db developers of the client/server architecture; when they attack the web2.0 problems, they fail because they stick to dogmatic notions as if they are true. Though (2) people are ignorant of relational concepts, (0) people are stubborn, uneducatable people who end up creating all types of scalibility problems. They overuse the notions of normalization, but forget they attack the wrong problem with the wrong tools.

PS: I am not yet using NoSQL in production and have a solid past in Oracle/Db2/Ms SQL/Sybase, and now now doing startups in MySQL/Postgres and Mongo.

Your group (3) is just his group (1) stated differently.

He denormalized the data.

yea, I show the nosql way by repeating the data.

I have to disagree with you. Normalisation is a very basic concept. Whilst it can cause a couple of problems, I am very sceptical about most startups hitting them. I'd like to see DBs introduce denormalisation as a feature, separating the logic from practicality.

Having said this, I like working with MongoDB. I like schemaless design and flexibility.

I was just going to write similar thing. This shows that there is a significant percentage of HN users, who haven't had formal introduction to basic CS concepts.

I'm one of those people. I was your typical web monkey, learning everything from how-to guides and O'Reilly books. Luckily I had the chance to read O'Reilly's Oracle Design (1997), which is actually a cleverly disguised general purpose RDBMS design handbook, including a good description of the normalized forms.

The upvotes could also mean that people appreciate a good presentation of introductory material, and they may see a use for it as something to send to the newbies on their team.

For this subject, I usually send people to Bill Kent's Guide to the Five Normal Forms: http://www.bkent.net/Doc/simple5.htm

I'm one of those. I keep a list of good intro material I can send to friends, nephews, etc, who want to learn programming. HN and reddit are two good sources of those kinds of posts.

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