This document explains how to set, add, or update individual documents in Cloud Firestore. To write data in bulk, see Transactions and batched writes.
Overview
You can write data to Cloud Firestore in one of the following ways:
- Set the data of a document within a collection, explicitly specifying a document identifier.
- Add a new document to a collection. In this case, Cloud Firestore automatically generates the document identifier.
- Create an empty document with an automatically generated identifier, and assign data to it later.
Before you begin
Before you can initialize Cloud Firestore to set, add, or update data, you must complete the following steps:
- Create a Cloud Firestore database. For more information, see Get started with Cloud Firestore
- If you use the web or mobile client libraries, authenticate with security rules. For more information, see Getting started with security rules.
- If you use the server client libraries or REST API, authenticate with Identity and Access Management (IAM). For more information, see Security for server client libraries.
Initialize Cloud Firestore
Initialize an instance of Cloud Firestore:
import { initializeApp } from "firebase/app"; import { getFirestore } from "firebase/firestore"; // TODO: Replace the following with your app's Firebase project configuration // See: https://support.google.com/firebase/answer/7015592 const firebaseConfig = {FIREBASE_CONFIGURATION }; // Initialize Firebase const app = initializeApp(firebaseConfig); // Initialize Cloud Firestore and get a reference to the service const db = getFirestore(app);
Replace FIREBASE_CONFIGURATION with your web app's
firebaseConfig
.
To persist data when the device loses its connection, see the Enable Offline Data documentation.
import firebase from "firebase/app"; import "firebase/firestore"; // TODO: Replace the following with your app's Firebase project configuration // See: https://support.google.com/firebase/answer/7015592 const firebaseConfig = {FIREBASE_CONFIGURATION }; // Initialize Firebase firebase.initializeApp(firebaseConfig); // Initialize Cloud Firestore and get a reference to the service const db = firebase.firestore();
Replace FIREBASE_CONFIGURATION with your web app's
firebaseConfig
.
To persist data when the device loses its connection, see the Enable Offline Data documentation.
import FirebaseCore import FirebaseFirestore
FirebaseApp.configure() let db = Firestore.firestore()
@import FirebaseCore; @import FirebaseFirestore; // Use Firebase library to configure APIs [FIRApp configure];
FIRFirestore *defaultFirestore = [FIRFirestore firestore];
// Access a Cloud Firestore instance from your Activity
val db = Firebase.firestore
// Access a Cloud Firestore instance from your Activity
FirebaseFirestore db = FirebaseFirestore.getInstance();
db = FirebaseFirestore.instance;
import com.google.auth.oauth2.GoogleCredentials; import com.google.cloud.firestore.Firestore; import com.google.firebase.FirebaseApp; import com.google.firebase.FirebaseOptions; // Use the application default credentials GoogleCredentials credentials = GoogleCredentials.getApplicationDefault(); FirebaseOptions options = new FirebaseOptions.Builder() .setCredentials(credentials) .setProjectId(projectId) .build(); FirebaseApp.initializeApp(options); Firestore db = FirestoreClient.getFirestore();
To use the Firebase Admin SDK on your own server, use a service account.
Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:
import com.google.auth.oauth2.GoogleCredentials; import com.google.cloud.firestore.Firestore; import com.google.firebase.FirebaseApp; import com.google.firebase.FirebaseOptions; // Use a service account InputStream serviceAccount = new FileInputStream("path/to/serviceAccount.json "); GoogleCredentials credentials = GoogleCredentials.fromStream(serviceAccount); FirebaseOptions options = new FirebaseOptions.Builder() .setCredentials(credentials) .build(); FirebaseApp.initializeApp(options); Firestore db = FirestoreClient.getFirestore();
import firebase_admin from firebase_admin import firestore # Application Default credentials are automatically created. app = firebase_admin.initialize_app() db = firestore.client()
An existing application default credential can also be used to initialize the SDK.
import firebase_admin from firebase_admin import credentials from firebase_admin import firestore # Use the application default credentials. cred = credentials.ApplicationDefault() firebase_admin.initialize_app(cred) db = firestore.client()
To use the Firebase Admin SDK on your own server, use a service account.
Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:
import firebase_admin from firebase_admin import credentials from firebase_admin import firestore # Use a service account. cred = credentials.Certificate('path/to/serviceAccount.json') app = firebase_admin.initialize_app(cred) db = firestore.client()
import firebase_admin from firebase_admin import firestore_async # Application Default credentials are automatically created. app = firebase_admin.initialize_app() db = firestore_async.client()
An existing application default credential can also be used to initialize the SDK.
import firebase_admin from firebase_admin import credentials from firebase_admin import firestore_async # Use the application default credentials. cred = credentials.ApplicationDefault() firebase_admin.initialize_app(cred) db = firestore_async.client()
To use the Firebase Admin SDK on your own server, use a service account.
Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:
import firebase_admin from firebase_admin import credentials from firebase_admin import firestore_async # Use a service account. cred = credentials.Certificate('path/to/serviceAccount.json') app = firebase_admin.initialize_app(cred) db = firestore_async.client()
// Make sure the call to `Create()` happens some time before you call Firestore::GetInstance(). App::Create(); Firestore* db = Firestore::GetInstance();
-
Initialize on Cloud Functions
const { initializeApp, applicationDefault, cert } = require('firebase-admin/app'); const { getFirestore, Timestamp, FieldValue, Filter } = require('firebase-admin/firestore');
initializeApp(); const db = getFirestore();
-
Initialize on Google Cloud
const { initializeApp, applicationDefault, cert } = require('firebase-admin/app'); const { getFirestore, Timestamp, FieldValue, Filter } = require('firebase-admin/firestore');
initializeApp({ credential: applicationDefault() }); const db = getFirestore();
-
Initialize on your own server
To use the Firebase Admin SDK on your own server (or any other Node.js environment), use a service account. Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:
const { initializeApp, applicationDefault, cert } = require('firebase-admin/app'); const { getFirestore, Timestamp, FieldValue, Filter } = require('firebase-admin/firestore');
const serviceAccount = require('./path/to/serviceAccountKey.json'); initializeApp({ credential: cert(serviceAccount) }); const db = getFirestore();
import ( "log" firebase "firebase.google.com/go" "google.golang.org/api/option" ) // Use the application default credentials ctx := context.Background() conf := &firebase.Config{ProjectID: projectID} app, err := firebase.NewApp(ctx, conf) if err != nil { log.Fatalln(err) } client, err := app.Firestore(ctx) if err != nil { log.Fatalln(err) } defer client.Close()
To use the Firebase Admin SDK on your own server, use a service account.
Go to IAM & admin > Service accounts in the Google Cloud console. Generate a new private key and save the JSON file. Then use the file to initialize the SDK:
import ( "log" firebase "firebase.google.com/go" "google.golang.org/api/option" ) // Use a service account ctx := context.Background() sa := option.WithCredentialsFile("path/to/serviceAccount.json") app, err := firebase.NewApp(ctx, nil, sa) if err != nil { log.Fatalln(err) } client, err := app.Firestore(ctx) if err != nil { log.Fatalln(err) } defer client.Close()
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
using Firebase.Firestore; using Firebase.Extensions;
FirebaseFirestore db = FirebaseFirestore.DefaultInstance;
C#
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
Set a document
To create or overwrite a single document, use the following language-specific set()
methods:
Use the setDoc()
method:
import { doc, setDoc } from "firebase/firestore"; // Add a new document in collection "cities" await setDoc(doc(db, "cities", "LA"), { name: "Los Angeles", state: "CA", country: "USA" });
Use the set()
method:
// Add a new document in collection "cities" db.collection("cities").doc("LA").set({ name: "Los Angeles", state: "CA", country: "USA" }) .then(() => { console.log("Document successfully written!"); }) .catch((error) => { console.error("Error writing document: ", error); });
Use the setData()
method:
// Add a new document in collection "cities" do { try await db.collection("cities").document("LA").setData([ "name": "Los Angeles", "state": "CA", "country": "USA" ]) print("Document successfully written!") } catch { print("Error writing document: \(error)") }
Use the setData:
method:
// Add a new document in collection "cities" [[[self.db collectionWithPath:@"cities"] documentWithPath:@"LA"] setData:@{ @"name": @"Los Angeles", @"state": @"CA", @"country": @"USA" } completion:^(NSError * _Nullable error) { if (error != nil) { NSLog(@"Error writing document: %@", error); } else { NSLog(@"Document successfully written!"); } }];
Use the set()
method:
val city = hashMapOf( "name" to "Los Angeles", "state" to "CA", "country" to "USA", ) db.collection("cities").document("LA") .set(city) .addOnSuccessListener { Log.d(TAG, "DocumentSnapshot successfully written!") } .addOnFailureListener { e -> Log.w(TAG, "Error writing document", e) }
Use the set()
method:
Map<String, Object> city = new HashMap<>(); city.put("name", "Los Angeles"); city.put("state", "CA"); city.put("country", "USA"); db.collection("cities").document("LA") .set(city) .addOnSuccessListener(new OnSuccessListener<Void>() { @Override public void onSuccess(Void aVoid) { Log.d(TAG, "DocumentSnapshot successfully written!"); } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { Log.w(TAG, "Error writing document", e); } });
Use the set()
method:
final city = <String, String>{ "name": "Los Angeles", "state": "CA", "country": "USA" }; db .collection("cities") .doc("LA") .set(city) .onError((e, _) => print("Error writing document: $e"));
Use the set()
method:
Use the set()
method:
Use the set()
method:
Use the Set()
method:
// Add a new document in collection 'cities' db->Collection("cities") .Document("LA") .Set({{"name", FieldValue::String("Los Angeles")}, {"state", FieldValue::String("CA")}, {"country", FieldValue::String("USA")}}) .OnCompletion([](const Future<void>& future) { if (future.error() == Error::kErrorOk) { std::cout << "DocumentSnapshot successfully written!" << std::endl; } else { std::cout << "Error writing document: " << future.error_message() << std::endl; } });
Use the set()
method:
Use the Set()
method:
Use the set()
method:
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
Use the SetAsync()
method:
DocumentReference docRef = db.Collection("cities").Document("LA"); Dictionary<string, object> city = new Dictionary<string, object> { { "Name", "Los Angeles" }, { "State", "CA" }, { "Country", "USA" } }; docRef.SetAsync(city).ContinueWithOnMainThread(task => { Debug.Log("Added data to the LA document in the cities collection."); });
Use the SetAsync()
method:
Use the set()
method:
If the document does not exist, it will be created. If the document does exist, its contents will be overwritten with the newly provided data, unless you specify that the data should be merged into the existing document, as follows:
import { doc, setDoc } from "firebase/firestore"; const cityRef = doc(db, 'cities', 'BJ'); setDoc(cityRef, { capital: true }, { merge: true });
var cityRef = db.collection('cities').doc('BJ'); var setWithMerge = cityRef.set({ capital: true }, { merge: true });
// Update one field, creating the document if it does not exist. db.collection("cities").document("BJ").setData([ "capital": true ], merge: true)
// Write to the document reference, merging data with existing // if the document already exists [[[self.db collectionWithPath:@"cities"] documentWithPath:@"BJ"] setData:@{ @"capital": @YES } merge:YES completion:^(NSError * _Nullable error) { // ... }];
// Update one field, creating the document if it does not already exist. val data = hashMapOf("capital" to true) db.collection("cities").document("BJ") .set(data, SetOptions.merge())
// Update one field, creating the document if it does not already exist. Map<String, Object> data = new HashMap<>(); data.put("capital", true); db.collection("cities").document("BJ") .set(data, SetOptions.merge());
// Update one field, creating the document if it does not already exist. final data = {"capital": true}; db.collection("cities").doc("BJ").set(data, SetOptions(merge: true));
db->Collection("cities").Document("BJ").Set( {{"capital", FieldValue::Boolean(true)}}, SetOptions::Merge());
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
DocumentReference docRef = db.Collection("cities").Document("LA"); Dictionary<string, object> update = new Dictionary<string, object> { { "capital", false } }; docRef.SetAsync(update, SetOptions.MergeAll);
If you're not sure whether the document exists, pass the option to merge the new data with any existing document to avoid overwriting entire documents. For documents that contain maps, if you specify a set with a field that contains an empty map, the map field of the target document is overwritten.
Data types
Cloud Firestore lets you write a variety of data types inside a document, including strings, booleans, numbers, dates, null, and nested arrays and objects. Cloud Firestore always stores numbers as doubles, regardless of what type of number you use in your code.
import { doc, setDoc, Timestamp } from "firebase/firestore"; const docData = { stringExample: "Hello world!", booleanExample: true, numberExample: 3.14159265, dateExample: Timestamp.fromDate(new Date("December 10, 1815")), arrayExample: [5, true, "hello"], nullExample: null, objectExample: { a: 5, b: { nested: "foo" } } }; await setDoc(doc(db, "data", "one"), docData);
var docData = { stringExample: "Hello world!", booleanExample: true, numberExample: 3.14159265, dateExample: firebase.firestore.Timestamp.fromDate(new Date("December 10, 1815")), arrayExample: [5, true, "hello"], nullExample: null, objectExample: { a: 5, b: { nested: "foo" } } }; db.collection("data").doc("one").set(docData).then(() => { console.log("Document successfully written!"); });
let docData: [String: Any] = [ "stringExample": "Hello world!", "booleanExample": true, "numberExample": 3.14159265, "dateExample": Timestamp(date: Date()), "arrayExample": [5, true, "hello"], "nullExample": NSNull(), "objectExample": [ "a": 5, "b": [ "nested": "foo" ] ] ] do { try await db.collection("data").document("one").setData(docData) print("Document successfully written!") } catch { print("Error writing document: \(error)") }
NSDictionary *docData = @{ @"stringExample": @"Hello world!", @"booleanExample": @YES, @"numberExample": @3.14, @"dateExample": [FIRTimestamp timestampWithDate:[NSDate date]], @"arrayExample": @[@5, @YES, @"hello"], @"nullExample": [NSNull null], @"objectExample": @{ @"a": @5, @"b": @{ @"nested": @"foo" } } }; [[[self.db collectionWithPath:@"data"] documentWithPath:@"one"] setData:docData completion:^(NSError * _Nullable error) { if (error != nil) { NSLog(@"Error writing document: %@", error); } else { NSLog(@"Document successfully written!"); } }];
val docData = hashMapOf( "stringExample" to "Hello world!", "booleanExample" to true, "numberExample" to 3.14159265, "dateExample" to Timestamp(Date()), "listExample" to arrayListOf(1, 2, 3), "nullExample" to null, ) val nestedData = hashMapOf( "a" to 5, "b" to true, ) docData["objectExample"] = nestedData db.collection("data").document("one") .set(docData) .addOnSuccessListener { Log.d(TAG, "DocumentSnapshot successfully written!") } .addOnFailureListener { e -> Log.w(TAG, "Error writing document", e) }
Map<String, Object> docData = new HashMap<>(); docData.put("stringExample", "Hello world!"); docData.put("booleanExample", true); docData.put("numberExample", 3.14159265); docData.put("dateExample", new Timestamp(new Date())); docData.put("listExample", Arrays.asList(1, 2, 3)); docData.put("nullExample", null); Map<String, Object> nestedData = new HashMap<>(); nestedData.put("a", 5); nestedData.put("b", true); docData.put("objectExample", nestedData); db.collection("data").document("one") .set(docData) .addOnSuccessListener(new OnSuccessListener<Void>() { @Override public void onSuccess(Void aVoid) { Log.d(TAG, "DocumentSnapshot successfully written!"); } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { Log.w(TAG, "Error writing document", e); } });
final docData = { "stringExample": "Hello world!", "booleanExample": true, "numberExample": 3.14159265, "dateExample": Timestamp.now(), "listExample": [1, 2, 3], "nullExample": null }; final nestedData = { "a": 5, "b": true, }; docData["objectExample"] = nestedData; db .collection("data") .doc("one") .set(docData) .onError((e, _) => print("Error writing document: $e"));
MapFieldValue doc_data{ {"stringExample", FieldValue::String("Hello world!")}, {"booleanExample", FieldValue::Boolean(true)}, {"numberExample", FieldValue::Double(3.14159265)}, {"dateExample", FieldValue::Timestamp(Timestamp::Now())}, {"arrayExample", FieldValue::Array({FieldValue::Integer(1), FieldValue::Integer(2), FieldValue::Integer(3)})}, {"nullExample", FieldValue::Null()}, {"objectExample", FieldValue::Map( {{"a", FieldValue::Integer(5)}, {"b", FieldValue::Map( {{"nested", FieldValue::String("foo")}})}})}, }; db->Collection("data").Document("one").Set(doc_data).OnCompletion( [](const Future<void>& future) { if (future.error() == Error::kErrorOk) { std::cout << "DocumentSnapshot successfully written!" << std::endl; } else { std::cout << "Error writing document: " << future.error_message() << std::endl; } });
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
DocumentReference docRef = db.Collection("data").Document("one"); Dictionary<string, object> docData = new Dictionary<string, object> { { "stringExample", "Hello World" }, { "booleanExample", false }, { "numberExample", 3.14159265 }, { "nullExample", null }, { "arrayExample", new List<object>() { 5, true, "Hello" } }, { "objectExample", new Dictionary<string, object> { { "a", 5 }, { "b", true }, } }, }; docRef.SetAsync(docData);
Custom objects
Using Map
or Dictionary
objects to represent your documents is often
inconvenient, so Cloud Firestore supports writing documents with custom
classes. Cloud Firestore converts the objects to supported data types.
Using custom classes, you can rewrite the initial example in the following way:
class City { constructor (name, state, country ) { this.name = name; this.state = state; this.country = country; } toString() { return this.name + ', ' + this.state + ', ' + this.country; } } // Firestore data converter const cityConverter = { toFirestore: (city) => { return { name: city.name, state: city.state, country: city.country }; }, fromFirestore: (snapshot, options) => { const data = snapshot.data(options); return new City(data.name, data.state, data.country); } };
class City { constructor (name, state, country ) { this.name = name; this.state = state; this.country = country; } toString() { return this.name + ', ' + this.state + ', ' + this.country; } } // Firestore data converter var cityConverter = { toFirestore: function(city) { return { name: city.name, state: city.state, country: city.country }; }, fromFirestore: function(snapshot, options){ const data = snapshot.data(options); return new City(data.name, data.state, data.country); } };
public struct City: Codable { let name: String let state: String? let country: String? let isCapital: Bool? let population: Int64? enum CodingKeys: String, CodingKey { case name case state case country case isCapital = "capital" case population } }
// This isn't supported in Objective-C.
data class City( val name: String? = null, val state: String? = null, val country: String? = null, @field:JvmField // use this annotation if your Boolean field is prefixed with 'is' val isCapital: Boolean? = null, val population: Long? = null, val regions: List<String>? = null, )
Each custom class must have a public constructor that takes no arguments. In addition, the class must include a public getter for each property.
public class City { private String name; private String state; private String country; private boolean capital; private long population; private List<String> regions; public City() {} public City(String name, String state, String country, boolean capital, long population, List<String> regions) { // ... } public String getName() { return name; } public String getState() { return state; } public String getCountry() { return country; } public boolean isCapital() { return capital; } public long getPopulation() { return population; } public List<String> getRegions() { return regions; } }
class City { final String? name; final String? state; final String? country; final bool? capital; final int? population; final List<String>? regions; City({ this.name, this.state, this.country, this.capital, this.population, this.regions, }); factory City.fromFirestore( DocumentSnapshot<Map<String, dynamic>> snapshot, SnapshotOptions? options, ) { final data = snapshot.data(); return City( name: data?['name'], state: data?['state'], country: data?['country'], capital: data?['capital'], population: data?['population'], regions: data?['regions'] is Iterable ? List.from(data?['regions']) : null, ); } Map<String, dynamic> toFirestore() { return { if (name != null) "name": name, if (state != null) "state": state, if (country != null) "country": country, if (capital != null) "capital": capital, if (population != null) "population": population, if (regions != null) "regions": regions, }; } }
// This is not yet supported.
// Node.js uses JavaScript objects
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
[FirestoreData] public class City { [FirestoreProperty] public string Name { get; set; } [FirestoreProperty] public string State { get; set; } [FirestoreProperty] public string Country { get; set; } [FirestoreProperty] public bool Capital { get; set; } [FirestoreProperty] public long Population { get; set; } }
// This isn't supported in Ruby
import { doc, setDoc } from "firebase/firestore"; // Set with cityConverter const ref = doc(db, "cities", "LA").withConverter(cityConverter); await setDoc(ref, new City("Los Angeles", "CA", "USA"));
// Set with cityConverter db.collection("cities").doc("LA") .withConverter(cityConverter) .set(new City("Los Angeles", "CA", "USA"));
let city = City(name: "Los Angeles", state: "CA", country: "USA", isCapital: false, population: 5000000) do { try db.collection("cities").document("LA").setData(from: city) } catch let error { print("Error writing city to Firestore: \(error)") }
// This isn't supported in Objective-C.
val city = City( "Los Angeles", "CA", "USA", false, 5000000L, listOf("west_coast", "socal"), ) db.collection("cities").document("LA").set(city)
City city = new City("Los Angeles", "CA", "USA", false, 5000000L, Arrays.asList("west_coast", "sorcal")); db.collection("cities").document("LA").set(city);
final city = City( name: "Los Angeles", state: "CA", country: "USA", capital: false, population: 5000000, regions: ["west_coast", "socal"], ); final docRef = db .collection("cities") .withConverter( fromFirestore: City.fromFirestore, toFirestore: (City city, options) => city.toFirestore(), ) .doc("LA"); await docRef.set(city);
// This is not yet supported.
// Node.js uses JavaScript objects
// This isn't supported in PHP.
DocumentReference docRef = db.Collection("cities").Document("LA"); City city = new City { Name = "Los Angeles", State = "CA", Country = "USA", Capital = false, Population = 3900000L }; docRef.SetAsync(city);
// This isn't supported in Ruby.
Add a document
When you use set()
to create a document, you must specify an ID for the
document to create, as shown in the following example:
import { doc, setDoc } from "firebase/firestore"; await setDoc(doc(db, "cities", "new-city-id"), data);
db.collection("cities").doc("new-city-id").set(data);
db.collection("cities").document("new-city-id").setData(data)
[[[self.db collectionWithPath:@"cities"] documentWithPath:@"new-city-id"] setData:data];
db.collection("cities").document("new-city-id").set(data)
db.collection("cities").document("new-city-id").set(data);
db.collection("cities").doc("new-city-id").set({"name": "Chicago"});
db->Collection("cities").Document("SF").Set({/*some data*/});
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
db.Collection("cities").Document("new-city-id").SetAsync(city);
If there isn't a meaningful ID for the document, Cloud Firestore can
auto-generate an ID for you. You can call the following language-specific
add()
methods:
Use the addDoc()
method:
import { collection, addDoc } from "firebase/firestore"; // Add a new document with a generated id. const docRef = await addDoc(collection(db, "cities"), { name: "Tokyo", country: "Japan" }); console.log("Document written with ID: ", docRef.id);
Use the add()
method:
// Add a new document with a generated id. db.collection("cities").add({ name: "Tokyo", country: "Japan" }) .then((docRef) => { console.log("Document written with ID: ", docRef.id); }) .catch((error) => { console.error("Error adding document: ", error); });
Use the addDocument()
method:
// Add a new document with a generated id. do { let ref = try await db.collection("cities").addDocument(data: [ "name": "Tokyo", "country": "Japan" ]) print("Document added with ID: \(ref.documentID)") } catch { print("Error adding document: \(error)") }
Use the addDocumentWithData:
method:
// Add a new document with a generated id. __block FIRDocumentReference *ref = [[self.db collectionWithPath:@"cities"] addDocumentWithData:@{ @"name": @"Tokyo", @"country": @"Japan" } completion:^(NSError * _Nullable error) { if (error != nil) { NSLog(@"Error adding document: %@", error); } else { NSLog(@"Document added with ID: %@", ref.documentID); } }];
Use the add()
method:
// Add a new document with a generated id. val data = hashMapOf( "name" to "Tokyo", "country" to "Japan", ) db.collection("cities") .add(data) .addOnSuccessListener { documentReference -> Log.d(TAG, "DocumentSnapshot written with ID: ${documentReference.id}") } .addOnFailureListener { e -> Log.w(TAG, "Error adding document", e) }
Use the add()
method:
// Add a new document with a generated id. Map<String, Object> data = new HashMap<>(); data.put("name", "Tokyo"); data.put("country", "Japan"); db.collection("cities") .add(data) .addOnSuccessListener(new OnSuccessListener<DocumentReference>() { @Override public void onSuccess(DocumentReference documentReference) { Log.d(TAG, "DocumentSnapshot written with ID: " + documentReference.getId()); } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { Log.w(TAG, "Error adding document", e); } });
Use the add()
method:
// Add a new document with a generated id. final data = {"name": "Tokyo", "country": "Japan"}; db.collection("cities").add(data).then((documentSnapshot) => print("Added Data with ID: ${documentSnapshot.id}"));
Use the add()
method:
Use the add()
method:
Use the add()
method:
Use the Add()
method:
db->Collection("cities").Add({/*some data*/});
Use the add()
method:
Use the Add()
method:
Use the add()
method:
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
Use the AddAsync()
method:
Dictionary<string, object> city = new Dictionary<string, object> { { "Name", "Tokyo" }, { "Country", "Japan" } }; db.Collection("cities").AddAsync(city).ContinueWithOnMainThread(task => { DocumentReference addedDocRef = task.Result; Debug.Log(String.Format("Added document with ID: {0}.", addedDocRef.Id)); });
Use the AddAsync()
method:
Use the add()
method:
In some cases, it can be useful to create a document reference with an
auto-generated ID, then use the reference later. For this use case, you can call
doc()
in the following way:
import { collection, doc, setDoc } from "firebase/firestore"; // Add a new document with a generated id const newCityRef = doc(collection(db, "cities")); // later... await setDoc(newCityRef, data);
// Add a new document with a generated id. var newCityRef = db.collection("cities").doc(); // later... newCityRef.set(data);
let newCityRef = db.collection("cities").document() // later... newCityRef.setData([ // ... ])
FIRDocumentReference *newCityRef = [[self.db collectionWithPath:@"cities"] documentWithAutoID]; // later... [newCityRef setData:@{ /* ... */ }];
val data = HashMap<String, Any>() val newCityRef = db.collection("cities").document() // Later... newCityRef.set(data)
Map<String, Object> data = new HashMap<>(); DocumentReference newCityRef = db.collection("cities").document(); // Later... newCityRef.set(data);
// Add a new document with a generated id. final data = <String, dynamic>{}; final newCityRef = db.collection("cities").doc(); // Later... newCityRef.set(data);
DocumentReference new_city_ref = db->Collection("cities").Document();
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
DocumentReference addedDocRef = db.Collection("cities").Document(); Debug.Log(String.Format("Added document with ID: {0}.", addedDocRef.Id)); addedDocRef.SetAsync(city).ContinueWithOnMainThread(task => { Debug.Log(String.Format( "Added data to the {0} document in the cities collection.", addedDocRef.Id)); });
In the backend, .add(...)
and .doc().set(...)
are equivalent, so you can use
either option.
Update a document
To update some fields of a document without overwriting the entire document, use
the following language-specific update()
methods:
Use the updateDoc()
method:
import { doc, updateDoc } from "firebase/firestore"; const washingtonRef = doc(db, "cities", "DC"); // Set the "capital" field of the city 'DC' await updateDoc(washingtonRef, { capital: true });
Use the update()
method:
var washingtonRef = db.collection("cities").doc("DC"); // Set the "capital" field of the city 'DC' return washingtonRef.update({ capital: true }) .then(() => { console.log("Document successfully updated!"); }) .catch((error) => { // The document probably doesn't exist. console.error("Error updating document: ", error); });
Use the updateData()
method:
let washingtonRef = db.collection("cities").document("DC") // Set the "capital" field of the city 'DC' do { try await washingtonRef.updateData([ "capital": true ]) print("Document successfully updated") } catch { print("Error updating document: \(error)") }
Use the updateData:
method:
FIRDocumentReference *washingtonRef = [[self.db collectionWithPath:@"cities"] documentWithPath:@"DC"]; // Set the "capital" field of the city [washingtonRef updateData:@{ @"capital": @YES } completion:^(NSError * _Nullable error) { if (error != nil) { NSLog(@"Error updating document: %@", error); } else { NSLog(@"Document successfully updated"); } }];
Use the update()
method:
val washingtonRef = db.collection("cities").document("DC") // Set the "isCapital" field of the city 'DC' washingtonRef .update("capital", true) .addOnSuccessListener { Log.d(TAG, "DocumentSnapshot successfully updated!") } .addOnFailureListener { e -> Log.w(TAG, "Error updating document", e) }
Use the update()
method:
DocumentReference washingtonRef = db.collection("cities").document("DC"); // Set the "isCapital" field of the city 'DC' washingtonRef .update("capital", true) .addOnSuccessListener(new OnSuccessListener<Void>() { @Override public void onSuccess(Void aVoid) { Log.d(TAG, "DocumentSnapshot successfully updated!"); } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { Log.w(TAG, "Error updating document", e); } });
Use the update()
method:
final washingtonRef = db.collection("cites").doc("DC"); washingtonRef.update({"capital": true}).then( (value) => print("DocumentSnapshot successfully updated!"), onError: (e) => print("Error updating document $e"));
Use the update()
method:
Use the update()
method:
Use the update()
method:
Use the Update()
method:
DocumentReference washington_ref = db->Collection("cities").Document("DC"); // Set the "capital" field of the city "DC". washington_ref.Update({{"capital", FieldValue::Boolean(true)}});
Use the update()
method:
Use the Update()
method:
Use the update()
method:
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
Use the UpdateAsync()
method:
DocumentReference cityRef = db.Collection("cities").Document("new-city-id"); Dictionary<string, object> updates = new Dictionary<string, object> { { "Capital", false } }; cityRef.UpdateAsync(updates).ContinueWithOnMainThread(task => { Debug.Log( "Updated the Capital field of the new-city-id document in the cities collection."); }); // You can also update a single field with: cityRef.UpdateAsync("Capital", false);
Use the UpdateAsync()
method:
Use the update()
method:
Server Timestamp
You can set a field in your document to a server timestamp which tracks when the server receives the update.
import { updateDoc, serverTimestamp } from "firebase/firestore"; const docRef = doc(db, 'objects', 'some-id'); // Update the timestamp field with the value from the server const updateTimestamp = await updateDoc(docRef, { timestamp: serverTimestamp() });
var docRef = db.collection('objects').doc('some-id'); // Update the timestamp field with the value from the server var updateTimestamp = docRef.update({ timestamp: firebase.firestore.FieldValue.serverTimestamp() });
do { try await db.collection("objects").document("some-id").updateData([ "lastUpdated": FieldValue.serverTimestamp(), ]) print("Document successfully updated") } catch { print("Error updating document: \(error)") }
[[[self.db collectionWithPath:@"objects"] documentWithPath:@"some-id"] updateData:@{ @"lastUpdated": [FIRFieldValue fieldValueForServerTimestamp] } completion:^(NSError * _Nullable error) { if (error != nil) { NSLog(@"Error updating document: %@", error); } else { NSLog(@"Document successfully updated"); } }];
// If you're using custom Kotlin objects in Android, add an @ServerTimestamp // annotation to a Date field for your custom object classes. This indicates // that the Date field should be treated as a server timestamp by the object mapper. val docRef = db.collection("objects").document("some-id") // Update the timestamp field with the value from the server val updates = hashMapOf<String, Any>( "timestamp" to FieldValue.serverTimestamp(), ) docRef.update(updates).addOnCompleteListener { }
// If you're using custom Java objects in Android, add an @ServerTimestamp // annotation to a Date field for your custom object classes. This indicates // that the Date field should be treated as a server timestamp by the object mapper. DocumentReference docRef = db.collection("objects").document("some-id"); // Update the timestamp field with the value from the server Map<String,Object> updates = new HashMap<>(); updates.put("timestamp", FieldValue.serverTimestamp()); docRef.update(updates).addOnCompleteListener(new OnCompleteListener<Void>() { // ... // ...
final docRef = db.collection("objects").doc("some-id"); final updates = <String, dynamic>{ "timestamp": FieldValue.serverTimestamp(), }; docRef.update(updates).then( (value) => print("DocumentSnapshot successfully updated!"), onError: (e) => print("Error updating document $e"));
DocumentReference doc_ref = db->Collection("objects").Document("some-id"); doc_ref.Update({{"timestamp", FieldValue::ServerTimestamp()}}) .OnCompletion([](const Future<void>& future) { // ... });
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
DocumentReference cityRef = db.Collection("cities").Document("new-city-id"); cityRef.UpdateAsync("Timestamp", FieldValue.ServerTimestamp) .ContinueWithOnMainThread(task => { Debug.Log( "Updated the Timestamp field of the new-city-id document in the cities " + "collection."); });
When updating multiple timestamp fields inside of a transaction, each field receives the same server timestamp value.
Update fields in nested objects
If your document contains nested objects, you can use the dot notation to
reference nested fields within the document when you call update()
:
import { doc, setDoc, updateDoc } from "firebase/firestore"; // Create an initial document to update. const frankDocRef = doc(db, "users", "frank"); await setDoc(frankDocRef, { name: "Frank", favorites: { food: "Pizza", color: "Blue", subject: "recess" }, age: 12 }); // To update age and favorite color: await updateDoc(frankDocRef, { "age": 13, "favorites.color": "Red" });
// Create an initial document to update. var frankDocRef = db.collection("users").doc("frank"); frankDocRef.set({ name: "Frank", favorites: { food: "Pizza", color: "Blue", subject: "recess" }, age: 12 }); // To update age and favorite color: db.collection("users").doc("frank").update({ "age": 13, "favorites.color": "Red" }) .then(() => { console.log("Document successfully updated!"); });
// Create an initial document to update. let frankDocRef = db.collection("users").document("frank") do { try await frankDocRef.setData([ "name": "Frank", "favorites": [ "food": "Pizza", "color": "Blue", "subject": "recess" ], "age": 12 ]) // To update age and favorite color: try await frankDocRef.updateData([ "age": 13, "favorites.color": "Red" ]) print("Document successfully updated") } catch { print("Error updating document: \(error)") }
// Create an initial document to update. FIRDocumentReference *frankDocRef = [[self.db collectionWithPath:@"users"] documentWithPath:@"frank"]; [frankDocRef setData:@{ @"name": @"Frank", @"favorites": @{ @"food": @"Pizza", @"color": @"Blue", @"subject": @"recess" }, @"age": @12 }]; // To update age and favorite color: [frankDocRef updateData:@{ @"age": @13, @"favorites.color": @"Red", } completion:^(NSError * _Nullable error) { if (error != nil) { NSLog(@"Error updating document: %@", error); } else { NSLog(@"Document successfully updated"); } }];
// Assume the document contains: // { // name: "Frank", // favorites: { food: "Pizza", color: "Blue", subject: "recess" } // age: 12 // } // // To update age and favorite color: db.collection("users").document("frank") .update( mapOf( "age" to 13, "favorites.color" to "Red", ), )
// Assume the document contains: // { // name: "Frank", // favorites: { food: "Pizza", color: "Blue", subject: "recess" } // age: 12 // } // // To update age and favorite color: db.collection("users").document("frank") .update( "age", 13, "favorites.color", "Red" );
// Assume the document contains: // { // name: "Frank", // favorites: { food: "Pizza", color: "Blue", subject: "recess" } // age: 12 // } db .collection("users") .doc("frank") .update({"age": 13, "favorites.color": "Red"});
// Assume the document contains: // { // name: "Frank", // favorites: { food: "Pizza", color: "Blue", subject: "recess" } // age: 12 // } // // To update age and favorite color: db->Collection("users").Document("frank").Update({ {"age", FieldValue::Integer(13)}, {"favorites.color", FieldValue::String("red")}, });
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
DocumentReference frankDocRef = db.Collection("users").Document("frank"); Dictionary<string, object> initialData = new Dictionary<string, object> { { "Name", "Frank" }, { "Age", 12 } }; Dictionary<string, object> favorites = new Dictionary<string, object> { { "Food", "Pizza" }, { "Color", "Blue" }, { "Subject", "Recess" }, }; initialData.Add("Favorites", favorites); frankDocRef.SetAsync(initialData).ContinueWithOnMainThread(task => { // Update age and favorite color Dictionary<string, object> updates = new Dictionary<string, object> { { "Age", 13 }, { "Favorites.Color", "Red" }, }; // Asynchronously update the document return frankDocRef.UpdateAsync(updates); }).ContinueWithOnMainThread(task => { Debug.Log( "Updated the age and favorite color fields of the Frank document in " + "the users collection."); });
Dot notation allows you to update a single nested field without overwriting other nested fields. If you update a nested field without dot notation, you will overwrite the entire map field, as shown in the following example:
// Create our initial doc db.collection("users").doc("frank").set({ name: "Frank", favorites: { food: "Pizza", color: "Blue", subject: "Recess" }, age: 12 }).then(function() { console.log("Frank created"); }); // Update the doc without using dot notation. // Notice the map value for favorites. db.collection("users").doc("frank").update({ favorites: { food: "Ice Cream" } }).then(function() { console.log("Frank food updated"); }); /* Ending State, favorite.color and favorite.subject are no longer present: /users /frank { name: "Frank", favorites: { food: "Ice Cream", }, age: 12 } */
Update elements in an array
If your document contains an array field, you can use arrayUnion()
and
arrayRemove()
to add and remove elements. arrayUnion()
adds elements to an
array but only elements not already present. arrayRemove()
removes all
instances of each given element.
import { doc, updateDoc, arrayUnion, arrayRemove } from "firebase/firestore"; const washingtonRef = doc(db, "cities", "DC"); // Atomically add a new region to the "regions" array field. await updateDoc(washingtonRef, { regions: arrayUnion("greater_virginia") }); // Atomically remove a region from the "regions" array field. await updateDoc(washingtonRef, { regions: arrayRemove("east_coast") });
var washingtonRef = db.collection("cities").doc("DC"); // Atomically add a new region to the "regions" array field. washingtonRef.update({ regions: firebase.firestore.FieldValue.arrayUnion("greater_virginia") }); // Atomically remove a region from the "regions" array field. washingtonRef.update({ regions: firebase.firestore.FieldValue.arrayRemove("east_coast") });
let washingtonRef = db.collection("cities").document("DC") // Atomically add a new region to the "regions" array field. washingtonRef.updateData([ "regions": FieldValue.arrayUnion(["greater_virginia"]) ]) // Atomically remove a region from the "regions" array field. washingtonRef.updateData([ "regions": FieldValue.arrayRemove(["east_coast"]) ])
FIRDocumentReference *washingtonRef = [[self.db collectionWithPath:@"cities"] documentWithPath:@"DC"]; // Atomically add a new region to the "regions" array field. [washingtonRef updateData:@{ @"regions": [FIRFieldValue fieldValueForArrayUnion:@[@"greater_virginia"]] }]; // Atomically remove a new region to the "regions" array field. [washingtonRef updateData:@{ @"regions": [FIRFieldValue fieldValueForArrayRemove:@[@"east_coast"]] }];
val washingtonRef = db.collection("cities").document("DC") // Atomically add a new region to the "regions" array field. washingtonRef.update("regions", FieldValue.arrayUnion("greater_virginia")) // Atomically remove a region from the "regions" array field. washingtonRef.update("regions", FieldValue.arrayRemove("east_coast"))
DocumentReference washingtonRef = db.collection("cities").document("DC"); // Atomically add a new region to the "regions" array field. washingtonRef.update("regions", FieldValue.arrayUnion("greater_virginia")); // Atomically remove a region from the "regions" array field. washingtonRef.update("regions", FieldValue.arrayRemove("east_coast"));
final washingtonRef = db.collection("cities").doc("DC"); // Atomically add a new region to the "regions" array field. washingtonRef.update({ "regions": FieldValue.arrayUnion(["greater_virginia"]), }); // Atomically remove a region from the "regions" array field. washingtonRef.update({ "regions": FieldValue.arrayRemove(["east_coast"]), });
// This is not yet supported.
// Not supported yet
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
// This is not yet supported in the Unity SDK
// Not supported yet
Increment a numeric value
You can increment or decrement a numeric field value as shown in the following example. An increment operation increases or decreases the current value of a field by the given amount.
import { doc, updateDoc, increment } from "firebase/firestore"; const washingtonRef = doc(db, "cities", "DC"); // Atomically increment the population of the city by 50. await updateDoc(washingtonRef, { population: increment(50) });
var washingtonRef = db.collection('cities').doc('DC'); // Atomically increment the population of the city by 50. washingtonRef.update({ population: firebase.firestore.FieldValue.increment(50) });
let washingtonRef = db.collection("cities").document("DC") // Atomically increment the population of the city by 50. // Note that increment() with no arguments increments by 1. washingtonRef.updateData([ "population": FieldValue.increment(Int64(50)) ])
FIRDocumentReference *washingtonRef = [[self.db collectionWithPath:@"cities"] documentWithPath:@"DC"]; // Atomically increment the population of the city by 50. // Note that increment() with no arguments increments by 1. [washingtonRef updateData:@{ @"population": [FIRFieldValue fieldValueForIntegerIncrement:50] }];
val washingtonRef = db.collection("cities").document("DC") // Atomically increment the population of the city by 50. washingtonRef.update("population", FieldValue.increment(50))
DocumentReference washingtonRef = db.collection("cities").document("DC"); // Atomically increment the population of the city by 50. washingtonRef.update("population", FieldValue.increment(50));
var washingtonRef = db.collection('cities').doc('DC'); // Atomically increment the population of the city by 50. washingtonRef.update( {"population": FieldValue.increment(50)}, );
// This is not yet supported.
PHP
For more on installing and creating a Cloud Firestore client, refer to Cloud Firestore Client Libraries.
// This is not yet supported in the Unity SDK.
Increment operations are useful for implementing counters. Note that updating a single document too quickly can lead to contention or errors. If you need to update your counter at a very high rate, see the Distributed counters page.