title: MongoDB - Unset an attribute from a single array element
body: <p>How can I unset an attribute from a single array element from the Mongo console.
  For example, how do I unset the junk attribute from time[1] </p>
  
  <pre><code>{
    "_id" : ObjectId("4d525ab2924f0000000022ad"), 
    "name" : "hello", 
    "time" : [
        {
            "stamp" : "2010-07-01T12:01:03.75+02:00",
            "reason" : "new"
        },
        {
            "stamp" : "2010-07-02T16:03:48.187+03:00",
            "reason" : "update",
            "junk"  : "yes"
        },
        {
            "stamp" : "2010-07-02T16:03:48.187+04:00",
            "reason" : "update"
        },
  
     ]
  }
  </code></pre>