javascript - Update all child in Firebase - Stack Overflow

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In a database from Firebase, I need to update the value open and pass it to false for all child. How I can do it in Javascript ? Something like this

let dbCon = firebase.database().ref("/messages/" + *);
    dbCon.update({
      open: false
    });

In a database from Firebase, I need to update the value open and pass it to false for all child. How I can do it in Javascript ? Something like this

let dbCon = firebase.database().ref("/messages/" + *);
    dbCon.update({
      open: false
    });

• javascript
• json
• reactjs
• firebase
• firebase-realtime-database

Share Improve this question Follow edited Apr 8, 2018 at 14:33 Frank van Puffelen 600k8585 gold badges890890 silver badges860860 bronze badges asked Apr 8, 2018 at 11:18 Monsieur SamMonsieur Sam 33311 gold badge77 silver badges2020 bronze badges 3

• Update your state through a for loop or so? Your state should be synced to Firebase? – Satej S Commented Apr 8, 2018 at 11:25
• I edit it to explain, yes it have to be synced to firebase – Monsieur Sam Commented Apr 8, 2018 at 11:28
• 1 Check out github./tylermcginnis/re-base – Satej S Commented Apr 8, 2018 at 11:44

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1 Answer 1

Sorted by: Reset to default 12

The Firebase Database has no equivalent to SQL's UPDATE messages SET open=false.

To update a node in Firebase, you must first have a reference to that specific node. And to get a reference to a node, you must know the full path to that node.

This means that you'll first need to read the data, then loop over it, and then update each child in turn. In code:

let dbCon = firebase.database().ref("/messages/");
dbCon.once("value", function(snapshot) {
  snapshot.forEach(function(child) {
    child.ref.update({
      open: false
    });
  });
});

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