query from firebase realtime database

Question

I am trying to get filtered data from my realtime database. In this example I want to get only these once with a specific uid:

I tried to get the data with the snippet from the firebase docs:

const db = getDatabase();
const auth = getAuth();
    
const myUserId = auth.currentUser.uid;
const myOffersRef = query(ref(db, 'allOffers/'), orderByChild('uid'), startAt(user.uid));

But how do I get the data from the const myOffersRef ?

Thank you!

Answer 1

As shown in the documentation on reading data , you can use get to get the data at a path or for a query.

const myOffersRef = query(ref(db, 'allOffers/'), orderByChild('uid'), equalTo(user.uid));

get(myOffersRef).then((snapshot) => {
  snapshot.forEach((child) => {
    console.log(child.key, child.val().uid);
  });
}).catch((error) => {
  console.error(error);
});

Note that I also changed startAt to equalTo , as you likely only want the nodes that match the UID, not the slide of nodes starting from the first match (which is what startAt does).

The forEach is needed since a query can potentially have 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.