Database for social site
From some time now I'm making research about various types of databases. 
Main criteria is of course performance, safety of data (like no single point of fail) and scalability.

I was reading about scaling MySql, NoSql databases, HBase etc. We're assuming rapid grow of our "social" site so database must be easily scalable. NoSQL like Cassandra probably is good option, but I'm not sure if I can Imagine writing whole site using only NoSQL...


Anyone know witch database could be best for this type of web site?
Database for social site
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From some time now I'm making research about various types of databases. 
Main criteria is of course performance, safety of data (like no single point of fail) and scalability.

I was reading about scaling MySql, NoSql databases, HBase etc. We're assuming rapid grow of our "social" site so database must be easily scalable. NoSQL like Cassandra probably is good option, but I'm not sure if I can Imagine writing whole site using only NoSQL...


Anyone know witch database could be best for this type of web site?