title: Is it better to have one collection with a billion or one thousand with one million objects?
body: <p>How much will performance differ between one NoSQL database (MongoDB) containing single collection - <code>logs</code> - with 1 billion entries or one thousand collections (<code>logs_source0</code>, <code>logs_source1</code>)? Will this change if the data is sharded across multiple servers? Objects contain between 6 and 10 keys and sometimes one array of 3-5 objects. The design of the application can use either one of these, as <code>_sourceX</code> can be easily turned into an extra key or vice versa.</p>