How to get the data from all the subcollection from all the Users from firebase?

user_18538604 0
Viewed 69

I have data something like Customer -> documnetid -> Orders(collection) same as for all customer. I need to show the list of orders from all the customer in a list. If a customer orders a item again it needs to create another list.

FirebaseFirestore.instance
        .collection("customer")
        .doc('a44d4c1b-7faa-4139-b707-a40499fe4ce5')
        .collection("orders")
        .where('orderStatus', isEqualTo: 'ordered')
        .snapshots(),

I can get the data if I provide specific document id. But I need to get orders from all the customers. Please help me in this. Thank you

google-cloud-firestore firebase dart flutter
2 Answers

You should use a Collection Group query, as explained in the Firebase documentation and in the Dart cloud_firestore package documentation.

Something along these lines:

FirebaseFirestore.instance
    .collectionGroup("orders")
    .where('orderStatus', isEqualTo: 'ordered')
    .get()
    .then((QuerySnapshot querySnapshot) {
        querySnapshot.docs.forEach((doc) {
            //...
        });
    });
user_33718620

You need to change your data structure. Like you can create a new different separate collection for orders with the same fields + customer id field.

so you can get all orders and orders by customer id

So if you want to get an orders for a particular customer you can get by this :

FirebaseFirestore.instance
    .collection("orders")
    .where('customerId', isEqualTo: 'a44d4c1b-7faa-4139-b707-a40499fe4ce5')
    .snapshots(),

And you can get all orders like this:

    FirebaseFirestore.instance
    .collection("orders")
    .snapshots(),

OR if you still want to do it by your data structure you can do it by loop

List orders = [];
          
          FirebaseFirestore.instance
              .collection('customer')
              .get().then((QuerySnapshot querySnapshot) {
            querySnapshot.docs.forEach((doc) {
              dynamic data = doc.data();
              orders.addAll(data['orders'] as List);
            });
          });
user_189389810
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