where can noSql be successfully implemented?

I took the time and see the entire Hadi Hariri present开发者_开发问答ation of CouchDB for .NET Developers that took place in OreDev conference last year.

And I keep asking myself, where should I use such way to store data?

What small, medium and large examples can be took using a noSQL model?

In what application context I would save the data in JSON, and that do not follow a pattern? In what application context the retrieving of such data would be better and faster (along the application time) comparing to the process of getting from a SQL server? Licencing price? Is that the only one?

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Let me share our case: we use a NoSQL system of document type to store and search our documents in full text. This requires a full-text indexing. We also do a facet search on the entire data. That is, we produce only "hit" count for a specific search broke down to some categories that we need. You can imagine an electronic shop selling photo cameras, so the facet search here can take place in price ranges. Thus you would be able to say, to which price range what types of cameras belong.

If you think about using a NoSQL system for document search, then small dataset would be order of GB's (let's say up to 10), a medium up to 100GB and large dataset of size up to 1TB. This is based on what I have seen people use Apache SOLR (from their mail-list) and what data volume we have in our company.

There are other types of NoSQL systems and associated use / business cases, where you can utilize them in conjuction with SQL systems or alone. You can have a look on this short PP presentation I made for an introductory talk on NoSQL systems: http://www.slideshare.net/dmitrykan/nosql-apache-solr-and-apache-hadoop