title: Firebase DB - How to update particular value of child in Firebase Database
body: <p>I want to update my display name in the code below. How can I update <code>displayName</code>?</p>
  
  <p>My database structure is:</p>
  
  <pre>
  -Users
        -KUanJA9egwmPsJCxXpv
  
           displayName:"Test Trainer"
  
           email:"test@gmail.com"
  
           uid: "jRXMsNZHR2exqifnR2rXcceEMxF2"
  </pre>