title: mongoDB. read, search timestamp based on oplog
body: <pre><code>&gt; db.oplog.rs.find({},{"ts":1}).sort({$natural: -1})
  { "ts" : Timestamp(1406185666, 1) }  
  { "ts" : Timestamp(1406180043, 1) }  
  { "ts" : Timestamp(1406180033, 1) }  
  { "ts" : Timestamp(1406172831, 1) }  
  { "ts" : Timestamp(1406171938, 1) }  
  { "ts" : Timestamp(1405915291, 1) }  
  { "ts" : Timestamp(1405915131, 1) }  
  { "ts" : Timestamp(1405915019, 1) }  
  { "ts" : Timestamp(1405914592, 1) }  
  { "ts" : Timestamp(1405914581, 1) }  
  { "ts" : Timestamp(1405587944, 1) }  
  { "ts" : Timestamp(1405587920, 1) }  
  { "ts" : Timestamp(1405587468, 1) }  
  { "ts" : Timestamp(1405587432, 1) }  
  { "ts" : Timestamp(1405587393, 1) }  
  { "ts" : Timestamp(1405587294, 1) }  
  { "ts" : Timestamp(1405587074, 1) }  
  { "ts" : Timestamp(1405586117, 1) }  
  { "ts" : Timestamp(1405586069, 1) }  
  { "ts" : Timestamp(1405586054, 1) }  
  </code></pre>
  
  <p>I have a series of timestamp example from oplog.rs in my database. I don't know how to read it</p>
  
  <p>My questions are:</p>
  
  <ol>
  <li>let's say that today is 13 aug 2014 8:28. I want to select all the oplog from the last hour</li>
  <li>I want to see all of the oplog from 12 aug 2014, from 9:00 to 15:00.</li>
  </ol>