title: mongodb .toArray vs .each (blocking vs async?)
body: <p>My question is which of the following is blocking and therefore not recommended for nodejs</p>
  
  <ol>
  <li><code>db.collection("allinfo").find({somekey: "someval"}).each(function(err, item){       //we get each item.... });</code></li>
  <li><code>db.collection("allinfo").find({somekey: "someval"}).toArray(function(err, allitems){ //we get whole array.... });</code></li>
  </ol>
  
  <p>Which one should be preferred and when?</p>