Query a subcollection

Demonstrates how to query a subcollection.

Explore further

For detailed documentation that includes this code sample, see the following:

• Get data with Cloud Firestore
• Getting data

Code sample

C#

To authenticate to Firestore, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

CollectionReference landmarks = db.Collection("cities").Document("SF").Collection("landmarks");
QuerySnapshot querySnapshot = await landmarks.GetSnapshotAsync();
foreach (DocumentSnapshot document in querySnapshot.Documents)
{
    Console.WriteLine($"{document.Reference.Path}: {document.GetValue<string>("Name")}");
}

Kotlin

db.collection("cities")
    .document("SF")
    .collection("landmarks")
    .get()
    .addOnSuccessListener { result ->
        for (document in result) {
            Log.d(TAG, "${document.id} => ${document.data}")
        }
    }
    .addOnFailureListener { exception ->
        Log.d(TAG, "Error getting documents: ", exception)
    }

What's next

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