title: Query from Redis depending on key value
body: <p><br>
  I need to write a node js application which will connect to REDIS based on a key and then update the key as per latest timestamp. This timestamp will be a property which will be present as the value of the key. <br>For e.g. client.set(key,object) , where <strong>key -- productId</strong> and <br>
  <strong>object -- 
  { <br>
  "productName" : "abc", <br>
  "make" : "abc",<br>
  "expiry" : "abc",<br>
  "timestamp": "333333"
  }</strong> <br>
  Is there any way where in I can get the timestamp and check if it is the latest or not and then update the record.I am currently using <strong>ioredis library</strong> with cluster feature</p>