老外写的NoSQL介绍性的文章《NoSQL : WHAT’S IN IT FOR ME》

jieforest

What about the maturity ?

Some solutions are very stable, but others have some key features yet to be implemented and bugs to be fixed.

The “polyglot database” approach

Each database has its own advantages and drawbacks. You have the choice, so do the right choice! Consider only your context requirements and do not try to choose only one database to do everything…

jieforest

Since few years the notion of “polyglot database” becomes to emerge.  It’s a response to the following problems :

- Very often an application uses different kinds of data

- It integrates information from different sources

- A unique technology (like a relational database) is not sufficient for all the users expectations

So, why not choose the best of breed for each domain (even in a single application) ?

jieforest

For example :

- User sessions stored in a “key-value” database (like Redis )

- Employees relationships stored in a “graph” database (like Neo4J)

-  The product catalog stored in a “document” database for flexibility (like MongoDB)

- The analytics data stored in a “key-columns” database (like Cassandra)

- Financial data stored in a “classical relational” database (like Oracle)