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!

CodePudding user response：

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 changes 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.