Query from Firebase dB

Question

I am new to Firebase and would like to know how to retrieve all the entries, given one specific value, like names. My db is like this:

{
  "-L6wXAM4Yt6OeUx6kLM9" : {
    "date" : "Tue Mar 06 14:17:53 GMT-04:00 2018",
    "names" : "Raamon"
  },
  "-L6wXAM84ti-Ea0vzKfx" : {
    "date" : "Tue Mar 06 14:17:53 GMT-04:00 2018",
    "names" : "Anne"
  },
  "-L6whnSSZXHxdjPvGgKI" : {
    "date" : "Tue Mar 06 15:08:41 GMT-04:00 2018",
    "names" : "Anne"
  }
}

My rules:

{
  "rules": {
    ".read": "auth == null",
    ".write": "auth == null"
  }
}

Should i use the Query function? Or something else?

Answer 1

Try this:

DatabaseReference ref = FirebaseDatabase.getInstance().getReference();
Query q = ref.orderByChild("names").equalTo(Raamon);
q.addListenerForSingleValueEvent(new ValueEventListener() {
   @Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot datas: dataSnapshot.getChildren()){
   String dates=datas.child("data").getValue().toString();
     }
   }   
   @Override 
 public void onCancelled(DatabaseError databaseError) {
      }
  });

using one specific value name that is equal to Raamon for example, you can then retrieve the date that is related to it.