Remove specific node from Firebase in JavaScript

user_14739251 0
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how do I remove this specific node in my database as shown in this picture below? (the nickname will be different since I'm just testing it, if anyone confuses) enter image description here

I've tried

    const roomRef = firebase.database().ref(`allRooms/${rooms}`);

    roomRef.orderByChild('nickname').equalTo(`${username}`).once('value',(snapshot)=> {  
                   snapshot.ref.remove();  })

But it just delete all of my nodes in that room, thank you

firebase-realtime-database firebase reactjs node.js javascript
2 Answers

You're almost there.

When you execute a query against the Firebase Database, there will potentially be multiple results. So the snapshot contains a list of those results. Even if there is only a single result, the snapshot will contain a list of one result. And your code needs to handle the fact that `` is a list with something like:

roomRef.orderByChild('nickname').equalTo(username).once('value',(snapshot)=> {
  snapshot.forEach((userSnapshot) => {  
    userSnapshot.ref.remove();  
  })
})

The above runs a separate remove() call for each matching node. If you have only one (or a few) nodes with the same name, this is probably fine. But if you have more of them, consider using a single multi-path update to remove all nodes like this:

roomRef.orderByChild('nickname').equalTo(username).once('value',(snapshot)=> {
  let updates = {};
  snapshot.forEach((userSnapshot) => {  
    updates[userSnapshot.key] = null; //  setting to null will remove the node
  })
  roomRef.update(updates); //  send all updates in one call
})
user_2091030

Here snapshot.ref will be roomRef itself therefore using remove() method on that will remove whole allRooms/roomId node. To delete that specific child node, you need a reference to that. Try this:

const roomRef = firebase.database().ref(`allRooms/${rooms}`);

roomRef.orderByChild('nickname').equalTo(`${username}`).once('value').then((snapshot) => {  
  if (snapshot.val()) {
    const keys = Object.keys(snapshot.val())
    snapshot.ref.child(keys[0]).remove().then(() => {
      //         ^^^^^ deleting that child instead of roomRef
      console.log("Data Deleted")
    }).catch(e => console.log(e));  
  }
})
user_131306970
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