title: Filtering in firebase json data by curl php
body: <p>how can I search data by email id "subu@gmail.com"?</p>
  
  <p>firebase data  </p>
  
  <pre><code>{
      "-K5swDCvGh-fWBC3rvzz": {
          "email": "subu@gmail.com",
          "facebook_id": "123456789",
          "password": "111",
          "source": "facebook",
          "username": "subu"
      },
      "-K5sxFSS4NC8tRRCtN-t": {
          "email": "subu_google@gmail.com",
          "google_id": "987456321",
          "password": "111",
          "source": "google",
          "username": "subu_google"
      }
  }
  </code></pre>
  
  <p>my data curl is </p>
  
  <pre><code>https://subu.firebaseio.com/users.json
  </code></pre>
  
  <p>my firebase rule is look below</p>
  
  <pre><code>{
      "rules": {
          "users": {
            ".indexOn": "email"
          },
          ".read": true,
          ".write": true
      }
  }
  </code></pre>