title: A partition tolerant relational database
body: <p>I'm looking for a database that achieves the following:</p>
  
  <ol>
  <li>fully ACID.</li>
  <li>relational with joins.</li>
  <li>has transactions.</li>
  <li>allows the administrator to specify sharding rules (for example: users from Europe should be located in the european data center).</li>
  <li><strong>the toughest requirement:</strong> upon network partition, like two datacenters disconnected from each other, each datacenter should be able to read and write to the nodes in it.
  Basically, I'm willing to sacrifice <strong>partial</strong> availability to partition tolerance. Sadly, most solutions will stall all reads and writes in case of a split-brain. (thus, preferring availability over partition tolerance)</li>
  </ol>