title: how to compare my contact with the contacts uploaded in firebase database
body: <p>Firstly I would like to show you my Firebase database tree</p>
  
  <pre><code>-Users
     |
     ----959670000
     |      |
     |      ------name
     |
     + ----750890000
     +------859200000
  </code></pre>
  
  <p>I had a root node with child as a user. whenever new user registers it got new Unique Id... and the unique Id is the phone number. Now In My Android Application I retrieve all my contacts i.e. phone number present in my mobile number. All I want is to compare Each phone number in my contact to the phone number present in the firebase database so that <strong>I would get to know which user in my contact had got registered.</strong></p>
  
  <p>All I am trying to ask are the ways to achieve the bold part in my question please Help me....I am very upset since the past 4 days and trying to achieve.
  Anyways thanx in Advance....:-)</p>