Is it possible to update only specific data on my child on firebase?

Question

Is it possible to only update the data of a certain user on my android Firebase?How can I do it, if for example I'm using an admin account where can I update all user specifically?

For example on my firebase database

I only want to update the user details of SCYQ--- I want to change the name,email,date. of the user only without affecting the information of other users?

Peter Haddad · Accepted Answer · 2018-02-21T12:15:51.410

6

Yes it is possible:

FirebaseUser user=FirebaseAuth.getInstance().getCurrentUser();
String useruid=user.getUid();
DatabaseReference ref=FirebaseDatabase.getInstance().getReference().child("Accounts").child("user").child(useruid);
ref.child("date").setValue(newdate);
ref.child("email").setValue(newemail);
ref.child("name").setValue(newname);
ref.child("type").setValue(newtype);

If you have the list of names in a listview and you want to update them then, you can do the following:

listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
final String selectedFromList = (String) listview.getItemAtPosition(position);
DatabaseReference ref=FirebaseDatabase.getInstance().getReference().child("Accounts").child("user").child(useruid);
ref.orderByChild("name").equalTo(selectedFromList).addValueEventListener(new ValueEventListener(){
 @Override
 public void onDataChange(DataSnapshot dataSnapshot) {

  //update values here
     }
  }

   @Override
 public void onCancelled(FirebaseError firebaseError) {

            }
        });
    });

edited Feb 21 '18 at 12:15

answered Feb 21 '18 at 10:54

Peter Haddad

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How can i do it, if for example I'm using an admin account where i can update all user specifically? – Yamiess Feb 21 '18 at 10:57
if you are using an admin account then you need to retrieve the data from the database to be able to update a user. The above gives you the uid of the current user – Peter Haddad Feb 21 '18 at 10:58
I managed to retrieve their data using list view simple_list_item. problem is I'm stuck on what step to take when i like to update them – Yamiess Feb 21 '18 at 11:02
do you have the list of names in the listview? – Peter Haddad Feb 21 '18 at 11:03
Thank you very much for this :D – Yamiess Feb 21 '18 at 12:44
How would i update the value btw? you get the value from the edit text? – Yamiess Feb 21 '18 at 12:45
You need to update all the values, you do that inside `onDatachange` like this `ref.child("date").setValue(newdate);`. To get value from edittext, you can do this `String txt=edittext.getText().toString()` – Peter Haddad Feb 21 '18 at 12:50
1

Sorry and thank you for this, I'll take your advice seriously sir – Yamiess Feb 21 '18 at 12:54

score 5 · Answer 2 · answered Feb 21 '18 at 15:27

While Peter's answer works, it will send four separate writes to the database. This in turn will fire listeners to that user data four times, which may not be what you want.

To update parts of a node in one go, use the updateChildren() method.

FirebaseUser user=FirebaseAuth.getInstance().getCurrentUser();
String useruid=user.getUid();
DatabaseReference ref=FirebaseDatabase.getInstance().getReference().child("Accounts").child("user").child(useruid);
Map<String, Object> updates = new HashMap<String,Object>();

updates.put("date", newdate);
updates.put("email", newemail);
updates.put("name", newname);
updates.put("type", newtype);

ref.updateChildren(updates);

This now sends all four values in a single update command, all failing or succeeding together, and leading to one update to other clients.

Also see the section update specific fields in the Firebase documentation.

answer makes a very good point here. Though Peter's answer is light, there is a huge advantage with Franks answer. That is: when working on a budget & loads of updates, you must realise, each setValue() will call your Cloud Functions Listener too, 4 times. That might be something you dont want as it would unnecessarily spike expenses. — Yo Apps, Jun 20 '19 at 08:59

Is it possible to update only specific data on my child on firebase?

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