The following examples demonstrate how to delete documents, fields, and collections.
Delete documents
To delete a document, use the delete() method:
Web
db.collection("cities").doc("DC").delete().then(function() {
console.log("Document successfully deleted!");
}).catch(function(error) {
console.error("Error removing document: ", error);
});
Swift
db.collection("cities").document("DC").delete() { err in
if let err = err {
print("Error removing document: \(err)")
} else {
print("Document successfully removed!")
}
}
Objective-C
[[[self.db collectionWithPath:@"cities"] documentWithPath:@"DC"]
deleteDocumentWithCompletion:^(NSError * _Nullable error) {
if (error != nil) {
NSLog(@"Error removing document: %@", error);
} else {
NSLog(@"Document successfully removed!");
}
}];
Java
db.collection("cities").document("DC")
.delete()
.addOnSuccessListener(new OnSuccessListener<Void>() {
@Override
public void onSuccess(Void aVoid) {
Log.d(TAG, "DocumentSnapshot successfully deleted!");
}
})
.addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Log.w(TAG, "Error deleting document", e);
}
});
Kotlin+KTX
db.collection("cities").document("DC")
.delete()
.addOnSuccessListener { Log.d(TAG, "DocumentSnapshot successfully deleted!") }
.addOnFailureListener { e -> Log.w(TAG, "Error deleting document", e) }
Java
// asynchronously delete a document
ApiFuture<WriteResult> writeResult = db.collection("cities").document("DC").delete();
// ...
System.out.println("Update time : " + writeResult.get().getUpdateTime());
Python
db.collection(u'cities').document(u'DC').delete()
C++
db->Collection("cities").Document("DC").Delete().OnCompletion(
[](const Future<void>& future) {
if (future.error() == Error::Ok) {
std::cout << "DocumentSnapshot successfully deleted!\n";
} else {
std::cout << "Error deleting document: " << future.error_message()
<< '\n';
}
});
Node.js
let deleteDoc = db.collection('cities').doc('DC').delete();
Go
_, err := client.Collection("cities").Doc("DC").Delete(ctx)
if err != nil {
// Handle any errors in an appropriate way, such as returning them.
log.Printf("An error has occurred: %s", err)
}
PHP
$db->collection('cities')->document('DC')->delete();
Unity
DocumentReference cityRef = db.Collection("cities").Document("DC");
cityRef.DeleteAsync();
C#
DocumentReference cityRef = db.Collection("cities").Document("DC");
await cityRef.DeleteAsync();
Ruby
city_ref = firestore.doc "cities/DC" city_ref.delete
When you delete a document, Cloud Firestore does not automatically
delete the documents within its
subcollections. You can still access the subcollection documents by reference.
For example, you can access the document at path
/mycoll/mydoc/mysubcoll/mysubdoc even
if you delete the ancestor document at /mycoll/mydoc.
Non-existent ancestor documents appear in the console, but they do not appear in query results and snapshots.
If you want to delete a document and all the documents within its subcollections, you must do so manually. For more information, see Delete Collections.
Delete fields
To delete specific fields from a document, use the FieldValue.delete() method
when you update a document:
Web
var cityRef = db.collection('cities').doc('BJ');
// Remove the 'capital' field from the document
var removeCapital = cityRef.update({
capital: firebase.firestore.FieldValue.delete()
});
Swift
db.collection("cities").document("BJ").updateData([
"capital": FieldValue.delete(),
]) { err in
if let err = err {
print("Error updating document: \(err)")
} else {
print("Document successfully updated")
}
}
Objective-C
[[[self.db collectionWithPath:@"cities"] documentWithPath:@"BJ"] updateData:@{
@"capital": [FIRFieldValue fieldValueForDelete]
} completion:^(NSError * _Nullable error) {
if (error != nil) {
NSLog(@"Error updating document: %@", error);
} else {
NSLog(@"Document successfully updated");
}
}];
Java
DocumentReference docRef = db.collection("cities").document("BJ");
// Remove the 'capital' field from the document
Map<String,Object> updates = new HashMap<>();
updates.put("capital", FieldValue.delete());
docRef.update(updates).addOnCompleteListener(new OnCompleteListener<Void>() {
// ...
// ...
Kotlin+KTX
val docRef = db.collection("cities").document("BJ")
// Remove the 'capital' field from the document
val updates = hashMapOf<String, Any>(
"capital" to FieldValue.delete()
)
docRef.update(updates).addOnCompleteListener { }
Java
DocumentReference docRef = db.collection("cities").document("BJ");
Map<String, Object> updates = new HashMap<>();
updates.put("capital", FieldValue.delete());
// Update and delete the "capital" field in the document
ApiFuture<WriteResult> writeResult = docRef.update(updates);
System.out.println("Update time : " + writeResult.get());
Python
city_ref = db.collection(u'cities').document(u'BJ')
city_ref.update({
u'capital': firestore.DELETE_FIELD
})
C++
DocumentReference doc_ref = db->Collection("cities").Document("BJ");
doc_ref.Update({{"capital", FieldValue::Delete()}})
.OnCompletion([](const Future<void>& future) { /*...*/ });
Node.js
// Get the `FieldValue` object
let FieldValue = require('firebase-admin').firestore.FieldValue;
// Create a document reference
let cityRef = db.collection('cities').doc('BJ');
// Remove the 'capital' field from the document
let removeCapital = cityRef.update({
capital: FieldValue.delete()
});
Go
_, err := client.Collection("cities").Doc("BJ").Update(ctx, []firestore.Update{
{
Path: "capital",
Value: firestore.Delete,
},
})
if err != nil {
// Handle any errors in an appropriate way, such as returning them.
log.Printf("An error has occurred: %s", err)
}
PHP
$cityRef = $db->collection('cities')->document('BJ');
$cityRef->update([
['path' => 'capital', 'value' => FieldValue::deleteField()]
]);
Unity
DocumentReference cityRef = db.Collection("cities").Document("BJ");
Dictionary<string, object> updates = new Dictionary<string, object>
{
{ "Capital", FieldValue.Delete }
};
C#
DocumentReference cityRef = db.Collection("cities").Document("BJ");
Dictionary<string, object> updates = new Dictionary<string, object>
{
{ "Capital", FieldValue.Delete }
};
await cityRef.UpdateAsync(updates);
Ruby
city_ref = firestore.doc "cities/BJ" city_ref.update capital: firestore.field_delete
Delete collections
To delete an entire collection or subcollection in Cloud Firestore, retrieve all the documents within the collection or subcollection and delete them. If you have larger collections, you may want to delete the documents in smaller batches to avoid out-of-memory errors. Repeat the process until you've deleted the entire collection or subcollection.
Deleting a collection requires coordinating an unbounded number of individual delete requests. If you need to delete entire collections, do so only from a trusted server environment. While it is possible to delete a collection from a mobile/web client, doing so has negative security and performance implications.
The snippets below are somewhat simplified and do not deal with error handling, security, deleting subcollections, or maximizing performance. To learn more about one recommended approach to deleting collections in production, see Deleting Collections and Subcollections.
Web
// Deleting collections from a Web client is not recommended.
Swift
// Deleting collections from an iOS client is not recommended.
Objective-C
// Deleting collections from an iOS client is not recommended.
Java
// Deleting collections from an Android client is not recommended.
Kotlin+KTX
// Deleting collections from an Android client is not recommended.
Java
/** Delete a collection in batches to avoid out-of-memory errors.
* Batch size may be tuned based on document size (atmost 1MB) and application requirements.
*/
void deleteCollection(CollectionReference collection, int batchSize) {
try {
// retrieve a small batch of documents to avoid out-of-memory errors
ApiFuture<QuerySnapshot> future = collection.limit(batchSize).get();
int deleted = 0;
// future.get() blocks on document retrieval
List<QueryDocumentSnapshot> documents = future.get().getDocuments();
for (QueryDocumentSnapshot document : documents) {
document.getReference().delete();
++deleted;
}
if (deleted >= batchSize) {
// retrieve and delete another batch
deleteCollection(collection, batchSize);
}
} catch (Exception e) {
System.err.println("Error deleting collection : " + e.getMessage());
}
}
Python
def delete_collection(coll_ref, batch_size):
docs = coll_ref.limit(batch_size).stream()
deleted = 0
for doc in docs:
print(u'Deleting doc {} => {}'.format(doc.id, doc.to_dict()))
doc.reference.delete()
deleted = deleted + 1
if deleted >= batch_size:
return delete_collection(coll_ref, batch_size)
C++
// This is not supported. Delete data using CLI as discussed below.
Node.js
function deleteCollection(db, collectionPath, batchSize) {
let collectionRef = db.collection(collectionPath);
let query = collectionRef.orderBy('__name__').limit(batchSize);
return new Promise((resolve, reject) => {
deleteQueryBatch(db, query, resolve, reject);
});
}
function deleteQueryBatch(db, query, resolve, reject) {
query.get()
.then((snapshot) => {
// When there are no documents left, we are done
if (snapshot.size === 0) {
return 0;
}
// Delete documents in a batch
let batch = db.batch();
snapshot.docs.forEach((doc) => {
batch.delete(doc.ref);
});
return batch.commit().then(() => {
return snapshot.size;
});
}).then((numDeleted) => {
if (numDeleted === 0) {
resolve();
return;
}
// Recurse on the next process tick, to avoid
// exploding the stack.
process.nextTick(() => {
deleteQueryBatch(db, query, resolve, reject);
});
})
.catch(reject);
}
Go
func deleteCollection(ctx context.Context, client *firestore.Client,
ref *firestore.CollectionRef, batchSize int) error {
for {
// Get a batch of documents
iter := ref.Limit(batchSize).Documents(ctx)
numDeleted := 0
// Iterate through the documents, adding
// a delete operation for each one to a
// WriteBatch.
batch := client.Batch()
for {
doc, err := iter.Next()
if err == iterator.Done {
break
}
if err != nil {
return err
}
batch.Delete(doc.Ref)
numDeleted++
}
// If there are no documents to delete,
// the process is over.
if numDeleted == 0 {
return nil
}
_, err := batch.Commit(ctx)
if err != nil {
return err
}
}
}
PHP
function delete_collection($collectionReference, $batchSize)
{
$documents = $collectionReference->limit($batchSize)->documents();
while (!$documents->isEmpty()) {
foreach ($documents as $document) {
printf('Deleting document %s' . PHP_EOL, $document->id());
$document->reference()->delete();
}
$documents = $collectionReference->limit($batchSize)->documents();
}
}
Unity
// This is not supported. Delete data using CLI as discussed below.
C#
private static async Task DeleteCollection(CollectionReference collectionReference, int batchSize)
{
QuerySnapshot snapshot = await collectionReference.Limit(batchSize).GetSnapshotAsync();
IReadOnlyList<DocumentSnapshot> documents = snapshot.Documents;
while (documents.Count > 0)
{
foreach (DocumentSnapshot document in documents)
{
Console.WriteLine("Deleting document {0}", document.Id);
await document.Reference.DeleteAsync();
}
snapshot = await collectionReference.Limit(batchSize).GetSnapshotAsync();
documents = snapshot.Documents;
}
Console.WriteLine("Finished deleting all documents from the collection.");
}
Ruby
cities_ref = firestore.col "cities"
query = cities_ref
query.get do |document_snapshot|
puts "Deleting document #{document_snapshot.document_id}."
document_ref = document_snapshot.ref
document_ref.delete
end
Delete data with the Firebase CLI
You can also use the Firebase CLI to delete documents and collections. Use the following command to delete data:
firebase firestore:delete [options] <<path>>