Agrega datos

Hay varias formas de escribir datos en Firestore:

  • Configurar los datos de un documento en una colección y especificar explícitamente un identificador de documento
  • Agregar un documento nuevo a una colección. En este caso, Firestore genera automáticamente el identificador de documento
  • Crear un documento vacío con un identificador generado automáticamente y asignarle datos más adelante

En esta guía se explica cómo usar los métodos para configurar, agregar o actualizar documentos individuales en Firestore. Si quieres escribir datos de forma masiva, consulta Transacciones y escrituras en lotes.

Configura un documento

Para crear o reemplazar un solo documento, usa el método set():

Web
// Add a new document in collection "cities"
db.collection("cities").doc("LA").set({
    name: "Los Angeles",
    state: "CA",
    country: "USA"
})
.then(function() {
    console.log("Document successfully written!");
})
.catch(function(error) {
    console.error("Error writing document: ", error);
});
Swift
// Add a new document in collection "cities"
db.collection("cities").document("LA").setData([
    "name": "Los Angeles",
    "state": "CA",
    "country": "USA"
]) { err in
    if let err = err {
        print("Error writing document: \(err)")
    } else {
        print("Document successfully written!")
    }
}
Objective-C
// 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!");
  }
}];
  
Java
Android
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);
            }
        });
Kotlin+KTX
Android
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) }
Java
// Create a Map to store the data we want to set
Map<String, Object> docData = new HashMap<>();
docData.put("name", "Los Angeles");
docData.put("state", "CA");
docData.put("country", "USA");
docData.put("regions", Arrays.asList("west_coast", "socal"));
// Add a new document (asynchronously) in collection "cities" with id "LA"
ApiFuture<WriteResult> future = db.collection("cities").document("LA").set(docData);
// ...
// future.get() blocks on response
System.out.println("Update time : " + future.get().getUpdateTime());
Python
data = {
    u'name': u'Los Angeles',
    u'state': u'CA',
    u'country': u'USA'
}

# Add a new doc in collection 'cities' with ID 'LA'
db.collection(u'cities').document(u'LA').set(data)
C++
// 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!\n";
      } else {
        std::cout << "Error writing document: " << future.error_message()
                  << '\n';
      }
    });
  
Node.js
const data = {
  name: 'Los Angeles',
  state: 'CA',
  country: 'USA'
};

// Add a new document in collection "cities" with ID 'LA'
const res = await db.collection('cities').doc('LA').set(data);
Go
_, err := client.Collection("cities").Doc("LA").Set(ctx, map[string]interface{}{
	"name":    "Los Angeles",
	"state":   "CA",
	"country": "USA",
})
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
$data = [
    'name' => 'Los Angeles',
    'state' => 'CA',
    'country' => 'USA'
];
$db->collection('cities')->document('LA')->set($data);
Unity
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.");
});
  
C#
DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> city = new Dictionary<string, object>
{
    { "name", "Los Angeles" },
    { "state", "CA" },
    { "country", "USA" }
};
await docRef.SetAsync(city);
Ruby
city_ref = firestore.doc "#{collection_path}/LA"

data = {
  name:    "Los Angeles",
  state:   "CA",
  country: "USA"
}

city_ref.set data

Si el documento no existe, se creará. Si el documento existe, su contenido se sobrescribirá con los datos proporcionados, a menos que especifiques que los datos se deberían combinar en el documento existente, de la siguiente manera:

Web
var cityRef = db.collection('cities').doc('BJ');

var setWithMerge = cityRef.set({
    capital: true
}, { merge: true });
Swift
// Update one field, creating the document if it does not exist.
db.collection("cities").document("BJ").setData([ "capital": true ], merge: true)
Objective-C
// 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) {
       // ...
     }];
  
Java
Android
// 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());
Kotlin+KTX
Android
// 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())
Java
//asynchronously update doc, create the document if missing
Map<String, Object> update = new HashMap<>();
update.put("capital", true);

ApiFuture<WriteResult> writeResult =
    db
        .collection("cities")
        .document("BJ")
        .set(update, SetOptions.merge());
// ...
System.out.println("Update time : " + writeResult.get().getUpdateTime());
Python
city_ref = db.collection(u'cities').document(u'BJ')

city_ref.set({
    u'capital': True
}, merge=True)
C++
db->Collection("cities").Document("BJ").Set(
    {{"capital", FieldValue::Boolean(true)}}, SetOptions::Merge());
  
Node.js
const cityRef = db.collection('cities').doc('BJ');

const res = await cityRef.set({
  capital: true
}, { merge: true });
Go
_, err := client.Collection("cities").Doc("BJ").Set(ctx, map[string]interface{}{
	"capital": true,
}, firestore.MergeAll)

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->set([
    'capital' => true
], ['merge' => true]);
Unity
DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> update = new Dictionary<string, object>
{
	{ "capital", false }
};
docRef.SetAsync(update, SetOptions.MergeAll);
  
C#
DocumentReference docRef = db.Collection("cities").Document("LA");
Dictionary<string, object> update = new Dictionary<string, object>
{
    { "capital", false }
};
await docRef.SetAsync(update, SetOptions.MergeAll);
Ruby
city_ref = firestore.doc "#{collection_path}/LA"
city_ref.set({ capital: false }, merge: true)

Si no estás seguro de la existencia del documento, no utilices la opción de combinar los datos nuevos con cualquier documento existente, para así evitar sobrescribir documentos completos.

Tipos de datos

Firestore te permite escribir diversos tipos de datos en un documento, como objetos y arreglos anidados, strings, valores booleanos, números, fechas y valores nulos. Firestore siempre almacena los números como valores de doble precisión, independientemente del tipo de número que uses en tu código.

Web
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(function() {
    console.log("Document successfully written!");
});
Swift
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"
        ]
    ]
]
db.collection("data").document("one").setData(docData) { err in
    if let err = err {
        print("Error writing document: \(err)")
    } else {
        print("Document successfully written!")
    }
}
Objective-C
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!");
      }
    }];
  
Java
Android
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);
            }
        });
Kotlin+KTX
Android
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) }
Java
Map<String, Object> docData = new HashMap<>();
docData.put("stringExample", "Hello, World");
docData.put("booleanExample", false);
docData.put("numberExample", 3.14159265);
docData.put("nullExample", null);

ArrayList<Object> arrayExample = new ArrayList<>();
Collections.addAll(arrayExample, 5L, true, "hello");
docData.put("arrayExample", arrayExample);

Map<String, Object> objectExample = new HashMap<>();
objectExample.put("a", 5L);
objectExample.put("b", true);

docData.put("objectExample", objectExample);

ApiFuture<WriteResult> future = db.collection("data").document("one").set(docData);
System.out.println("Update time : " + future.get().getUpdateTime());
Python
data = {
    u'stringExample': u'Hello, World!',
    u'booleanExample': True,
    u'numberExample': 3.14159265,
    u'dateExample': datetime.datetime.now(),
    u'arrayExample': [5, True, u'hello'],
    u'nullExample': None,
    u'objectExample': {
        u'a': 5,
        u'b': True
    }
}

db.collection(u'data').document(u'one').set(data)
C++
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!\n";
      } else {
        std::cout << "Error writing document: " << future.error_message()
                  << '\n';
      }
    });
  
Node.js
const data = {
  stringExample: 'Hello, World!',
  booleanExample: true,
  numberExample: 3.14159265,
  dateExample: admin.firestore.Timestamp.fromDate(new Date('December 10, 1815')),
  arrayExample: [5, true, 'hello'],
  nullExample: null,
  objectExample: {
    a: 5,
    b: true
  }
};

const res = await db.collection('data').doc('one').set(data);
Go
doc := make(map[string]interface{})
doc["stringExample"] = "Hello world!"
doc["booleanExample"] = true
doc["numberExample"] = 3.14159265
doc["dateExample"] = time.Now()
doc["arrayExample"] = []interface{}{5, true, "hello"}
doc["nullExample"] = nil
doc["objectExample"] = map[string]interface{}{
	"a": 5,
	"b": true,
}

_, err := client.Collection("data").Doc("one").Set(ctx, doc)
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
$data = [
    'stringExample' => 'Hello World',
    'booleanExample' => true,
    'numberExample' => 3.14159265,
    'dateExample' => new Timestamp(new DateTime()),
    'arrayExample' => array(5, true, 'hello'),
    'nullExample' => null,
    'objectExample' => ['a' => 5, 'b' => true],
    'documentReferenceExample' => $db->collection('data')->document('two'),
];
$db->collection('data')->document('one')->set($data);
printf('Set multiple data-type data for the one document in the data collection.' . PHP_EOL);
Unity
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);
  
C#
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 },
};

ArrayList arrayExample = new ArrayList();
arrayExample.Add(5);
arrayExample.Add(true);
arrayExample.Add("Hello");
docData.Add("arrayExample", arrayExample);

Dictionary<string, object> objectExample = new Dictionary<string, object>
{
    { "a", 5 },
    { "b", true },
};
docData.Add("objectExample", objectExample);

await docRef.SetAsync(docData);
Ruby
doc_ref = firestore.doc "#{collection_path}/one"

data = {
  stringExample:  "Hello, World!",
  booleanExample: true,
  numberExample:  3.14159265,
  dateExample:    DateTime.now,
  arrayExample:   [5, true, "hello"],
  nullExample:    nil,
  objectExample:  {
    a: 5,
    b: true
  }
}

doc_ref.set data

Objetos personalizados

Usar objetos Map o Dictionary para representar tus documentos suele ser poco práctico, por lo que Firestore también admite la escritura de documentos con clases personalizadas. Firestore convierte los objetos en tipos de datos compatibles.

Con las clases personalizadas podrías reescribir el ejemplo inicial de la siguiente manera:

Web
A fin de usar una clase personalizada, debes definir una función FirestoreDataConverter para tu clase. Por ejemplo:
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)
    }
}
Swift
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
    }

}
Objective-C
// This isn't supported in Objective-C.
  
Java
Android

Cada clase personalizada debe tener un constructor público que no acepte argumentos. Además, la clase debe incluir un captador método get para cada propiedad.

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;
    }

}
Kotlin+KTX
Android
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
)
Java
public City() {
  // Must have a public no-argument constructor
}

// Initialize all fields of a city
public City(String name, String state, String country,
            Boolean capital, Long population, List<String> regions) {
  this.name = name;
  this.state = state;
  this.country = country;
  this.capital = capital;
  this.population = population;
  this.regions = regions;
}
Python
class City(object):
    def __init__(self, name, state, country, capital=False, population=0,
                 regions=[]):
        self.name = name
        self.state = state
        self.country = country
        self.capital = capital
        self.population = population
        self.regions = regions

    @staticmethod
    def from_dict(source):
        # ...

    def to_dict(self):
        # ...

    def __repr__(self):
        return(
            f'City(\
                name={self.name}, \
                country={self.country}, \
                population={self.population}, \
                capital={self.capital}, \
                regions={self.regions}\
            )'
        )
C++
// This is not yet supported.
Node.js
// Node.js uses JavaScript objects
Go

// City represents a city.
type City struct {
	Name       string   `firestore:"name,omitempty"`
	State      string   `firestore:"state,omitempty"`
	Country    string   `firestore:"country,omitempty"`
	Capital    bool     `firestore:"capital,omitempty"`
	Population int64    `firestore:"population,omitempty"`
	Regions    []string `firestore:"regions,omitempty"`
}

PHP
// This isn't supported in PHP
Unity
[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; }
}
  
C#
[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; }
}
Ruby
// This isn't supported in Ruby
Web
Llama al convertidor de datos con la operación de escritura:
// Set with cityConverter
db.collection("cities").doc("LA")
  .withConverter(cityConverter)
  .set(new City("Los Angeles", "CA", "USA"));
Swift
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)")
}
Objective-C
// This isn't supported in Objective-C.
  
Java
Android
City city = new City("Los Angeles", "CA", "USA",
        false, 5000000L, Arrays.asList("west_coast", "sorcal"));
db.collection("cities").document("LA").set(city);
Kotlin+KTX
Android
val city = City("Los Angeles", "CA", "USA",
        false, 5000000L, listOf("west_coast", "socal"))
db.collection("cities").document("LA").set(city)
Java
City city = new City("Los Angeles", "CA", "USA", false, 3900000L,
    Arrays.asList("west_coast", "socal"));
ApiFuture<WriteResult> future = db.collection("cities").document("LA").set(city);
// block on response if required
System.out.println("Update time : " + future.get().getUpdateTime());
Python
city = City(name=u'Los Angeles', state=u'CA', country=u'USA')
db.collection(u'cities').document(u'LA').set(city.to_dict())
C++
// This is not yet supported.
Node.js
// Node.js uses JavaScript objects
Go
city := City{
	Name:    "Los Angeles",
	Country: "USA",
}
_, err := client.Collection("cities").Doc("LA").Set(ctx, city)
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
// This isn't supported in PHP.
Unity
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);
  
C#
DocumentReference docRef = db.Collection("cities").Document("LA");
City city = new City
{
    Name = "Los Angeles",
    State = "CA",
    Country = "USA",
    Capital = false,
    Population = 3900000L
};
await docRef.SetAsync(city);
Ruby
// This isn't supported in Ruby.

Agrega un documento

Cuando usas set() para crear un documento, debes especificar un ID para el documento que vas a crear. Por ejemplo:

Web
db.collection("cities").doc("new-city-id").set(data);
Swift
db.collection("cities").document("new-city-id").setData(data)
Objective-C
[[[self.db collectionWithPath:@"cities"] documentWithPath:@"new-city-id"]
    setData:data];
  
Java
Android
db.collection("cities").document("new-city-id").set(data);
Kotlin+KTX
Android
db.collection("cities").document("new-city-id").set(data)
Java
db.collection("cities").document("new-city-id").set(data);
Python
db.collection(u'cities').document(u'new-city-id').set(data)
C++
db->Collection("cities").Document("SF").Set({/*some data*/});
  
Node.js
await db.collection('cities').doc('new-city-id').set(data);
Go
_, err := client.Collection("cities").Doc("new-city-id").Set(ctx, data)
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
$db->collection('cities')->document('new-city-id')->set($data);
Unity
db.Collection("cities").Document("new-city-id").SetAsync(city);
  
C#
await db.Collection("cities").Document("new-city-id").SetAsync(city);
Ruby
city_ref = firestore.doc "#{collection_path}/new-city-id"
city_ref.set data

Sin embargo, en ocasiones no existe un ID significativo para el documento y es más conveniente dejar que Firestore genere uno de forma automática. Para hacerlo, llama a add():

Web
// Add a new document with a generated id.
db.collection("cities").add({
    name: "Tokyo",
    country: "Japan"
})
.then(function(docRef) {
    console.log("Document written with ID: ", docRef.id);
})
.catch(function(error) {
    console.error("Error adding document: ", error);
});
Swift
// Add a new document with a generated id.
var ref: DocumentReference? = nil
ref = db.collection("cities").addDocument(data: [
    "name": "Tokyo",
    "country": "Japan"
]) { err in
    if let err = err {
        print("Error adding document: \(err)")
    } else {
        print("Document added with ID: \(ref!.documentID)")
    }
}
Objective-C
// 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);
      }
    }];
  
Java
Android
// 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);
            }
        });
Kotlin+KTX
Android
// 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)
    }
Java
// Add document data with auto-generated id.
Map<String, Object> data = new HashMap<>();
data.put("name", "Tokyo");
data.put("country", "Japan");
ApiFuture<DocumentReference> addedDocRef = db.collection("cities").add(data);
System.out.println("Added document with ID: " + addedDocRef.get().getId());
Python
city = City(name=u'Tokyo', state=None, country=u'Japan')
db.collection(u'cities').add(city.to_dict())
C++
db->Collection("cities").Add({/*some data*/});
  
Node.js
// Add a new document with a generated id.
const res = await db.collection('cities').add({
  name: 'Tokyo',
  country: 'Japan'
});

console.log('Added document with ID: ', res.id);
Go
_, _, err := client.Collection("cities").Add(ctx, map[string]interface{}{
	"name":    "Tokyo",
	"country": "Japan",
})
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
$data = [
    'name' => 'Tokyo',
    'country' => 'Japan'
];
$addedDocRef = $db->collection('cities')->add($data);
printf('Added document with ID: %s' . PHP_EOL, $addedDocRef->id());
Unity
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));
});
  
C#
Dictionary<string, object> city = new Dictionary<string, object>
{
    { "Name", "Tokyo" },
    { "Country", "Japan" }
};
DocumentReference addedDocRef = await db.Collection("cities").AddAsync(city);
Console.WriteLine("Added document with ID: {0}.", addedDocRef.Id);
Ruby
data = {
  name:    "Tokyo",
  country: "Japan"
}

cities_ref = firestore.col collection_path

added_doc_ref = cities_ref.add data
puts "Added document with ID: #{added_doc_ref.document_id}."

En algunos casos, puede ser útil crear una referencia de documento con un ID generado automáticamente y, luego, usar la referencia más adelante. Para este caso práctico, puedes llamar a doc():

Web
// Add a new document with a generated id.
var newCityRef = db.collection("cities").doc();

// later...
newCityRef.set(data);
Swift
let newCityRef = db.collection("cities").document()

// later...
newCityRef.setData([
    // ...
])
Objective-C
FIRDocumentReference *newCityRef = [[self.db collectionWithPath:@"cities"] documentWithAutoID];
// later...
[newCityRef setData:@{ /* ... */ }];
  
Java
Android
Map<String, Object> data = new HashMap<>();

DocumentReference newCityRef = db.collection("cities").document();

// Later...
newCityRef.set(data);
Kotlin+KTX
Android
val data = HashMap<String, Any>()

val newCityRef = db.collection("cities").document()

// Later...
newCityRef.set(data)
Java
// Add document data after generating an id.
DocumentReference addedDocRef = db.collection("cities").document();
System.out.println("Added document with ID: " + addedDocRef.getId());

// later...
ApiFuture<WriteResult> writeResult = addedDocRef.set(data);
Python
new_city_ref = db.collection(u'cities').document()

# later...
new_city_ref.set({
    # ...
})
C++
DocumentReference new_city_ref = db->Collection("cities").Document();
  
Node.js
const newCityRef = db.collection('cities').doc();

// Later...
const res = await newCityRef.set({
  // ...
});
Go
ref := client.Collection("cities").NewDoc()

// later...
_, err := ref.Set(ctx, data)
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
$addedDocRef = $db->collection('cities')->newDocument();
printf('Added document with ID: %s' . PHP_EOL, $addedDocRef->id());
$addedDocRef->set($data);
Unity
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));
});
  
C#
DocumentReference addedDocRef = db.Collection("cities").Document();
Console.WriteLine("Added document with ID: {0}.", addedDocRef.Id);
await addedDocRef.SetAsync(city);
Ruby
cities_ref = firestore.col collection_path

added_doc_ref = cities_ref.doc
puts "Added document with ID: #{added_doc_ref.document_id}."

added_doc_ref.set data

En segundo plano, .add(...) y .doc().set(...) son completamente equivalentes, por lo que puedes usar lo que te resulte más conveniente.

Actualiza un documento

Para actualizar algunos campos de un documento sin reemplazarlo por completo, usa el método update():

Web
var washingtonRef = db.collection("cities").doc("DC");

// Set the "capital" field of the city 'DC'
return washingtonRef.update({
    capital: true
})
.then(function() {
    console.log("Document successfully updated!");
})
.catch(function(error) {
    // The document probably doesn't exist.
    console.error("Error updating document: ", error);
});
Swift
let washingtonRef = db.collection("cities").document("DC")

// Set the "capital" field of the city 'DC'
washingtonRef.updateData([
    "capital": true
]) { err in
    if let err = err {
        print("Error updating document: \(err)")
    } else {
        print("Document successfully updated")
    }
}
Objective-C
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");
  }
}];
  
Java
Android
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);
            }
        });
Kotlin+KTX
Android
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) }
Java
// Update an existing document
DocumentReference docRef = db.collection("cities").document("DC");

// (async) Update one field
ApiFuture<WriteResult> future = docRef.update("capital", true);

// ...
WriteResult result = future.get();
System.out.println("Write result: " + result);
Python
city_ref = db.collection(u'cities').document(u'DC')

# Set the capital field
city_ref.update({u'capital': True})
C++
DocumentReference washington_ref = db->Collection("cities").Document("DC");
// Set the "capital" field of the city "DC".
washington_ref.Update({{"capital", FieldValue::Boolean(true)}});
  
Node.js
const cityRef = db.collection('cities').doc('DC');

// Set the 'capital' field of the city
const res = await cityRef.update({capital: true});
Go
_, err = client.Collection("cities").Doc("DC").Update(ctx, []firestore.Update{
	{
		Path:  "capital",
		Value: true,
	},
})
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('DC');
$cityRef->update([
    ['path' => 'capital', 'value' => true]
]);
Unity
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);
  
C#
DocumentReference cityRef = db.Collection("cities").Document("new-city-id");
Dictionary<string, object> updates = new Dictionary<string, object>
{
    { "Capital", false }
};
await cityRef.UpdateAsync(updates);

// You can also update a single field with: await cityRef.UpdateAsync("Capital", false);
Ruby
city_ref = firestore.doc "#{collection_path}/DC"
city_ref.update capital: true

Marca de tiempo del servidor

Puedes configurar un campo en tu documento para una marca de tiempo de servidor que haga un seguimiento de cuando el servidor recibe la actualización.

Web
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()
});
Swift
db.collection("objects").document("some-id").updateData([
    "lastUpdated": FieldValue.serverTimestamp(),
]) { err in
    if let err = err {
        print("Error updating document: \(err)")
    } else {
        print("Document successfully updated")
    }
}
Objective-C
[[[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");
  }
}];
  
Java
Android
// 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>() {
    // ...
    // ...
Kotlin+KTX
Android
// 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 { }
Java
DocumentReference docRef = db.collection("objects").document("some-id");
// Update the timestamp field with the value from the server
ApiFuture<WriteResult> writeResult = docRef.update("timestamp", FieldValue.serverTimestamp());
System.out.println("Update time : " + writeResult.get());
Python
city_ref = db.collection(u'objects').document(u'some-id')
city_ref.update({
    u'timestamp': firestore.SERVER_TIMESTAMP
})
C++
DocumentReference doc_ref = db->Collection("objects").Document("some-id");
doc_ref.Update({{"timestamp", FieldValue::ServerTimestamp()}})
    .OnCompletion([](const Future<void>& future) {
      // ...
    });
  
Node.js
// Get the `FieldValue` object
const FieldValue = admin.firestore.FieldValue;

// Create a document reference
const docRef = db.collection('objects').doc('some-id');

// Update the timestamp field with the value from the server
const res = await docRef.update({
  timestamp: FieldValue.serverTimestamp()
});
Go
_, err := client.Collection("objects").Doc("some-id").Set(ctx, map[string]interface{}{
	"timestamp": firestore.ServerTimestamp,
}, firestore.MergeAll)
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
$docRef = $db->collection('objects')->document('some-id');
$docRef->update([
    ['path' => 'timestamp', 'value' => FieldValue::serverTimestamp()]
]);
Unity
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.");
	});
  
C#
DocumentReference cityRef = db.Collection("cities").Document("new-city-id");
await cityRef.UpdateAsync("Timestamp", Timestamp.GetCurrentTimestamp());
Ruby
city_ref = firestore.doc "#{collection_path}/new-city-id"
city_ref.update timestamp: firestore.field_server_time

Actualiza los campos en objetos anidados

Si tu documento contiene objetos anidados, puedes usar la notación de puntos para hacer referencia a los campos anidados dentro del documento cuando llames a update():

Web
// 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(function() {
    console.log("Document successfully updated!");
});
Swift
// Create an initial document to update.
let frankDocRef = db.collection("users").document("frank")
frankDocRef.setData([
    "name": "Frank",
    "favorites": [ "food": "Pizza", "color": "Blue", "subject": "recess" ],
    "age": 12
    ])

// To update age and favorite color:
db.collection("users").document("frank").updateData([
    "age": 13,
    "favorites.color": "Red"
]) { err in
    if let err = err {
        print("Error updating document: \(err)")
    } else {
        print("Document successfully updated")
    }
}
Objective-C
// 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");
  }
}];
  
Java
Android
// 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"
        );
Kotlin+KTX
Android
// 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"
        ))
Java
// Create an initial document to update
DocumentReference frankDocRef = db.collection("users").document("frank");
Map<String, Object> initialData = new HashMap<>();
initialData.put("name", "Frank");
initialData.put("age", 12);

Map<String, Object> favorites = new HashMap<>();
favorites.put("food", "Pizza");
favorites.put("color", "Blue");
favorites.put("subject", "Recess");
initialData.put("favorites", favorites);

ApiFuture<WriteResult> initialResult = frankDocRef.set(initialData);
// Confirm that data has been successfully saved by blocking on the operation
initialResult.get();

// Update age and favorite color
Map<String, Object> updates = new HashMap<>();
updates.put("age", 13);
updates.put("favorites.color", "Red");

// Async update document
ApiFuture<WriteResult> writeResult = frankDocRef.update(updates);
// ...
System.out.println("Update time : " + writeResult.get().getUpdateTime());
Python
# Create an initial document to update
frank_ref = db.collection(u'users').document(u'frank')
frank_ref.set({
    u'name': u'Frank',
    u'favorites': {
        u'food': u'Pizza',
        u'color': u'Blue',
        u'subject': u'Recess'
    },
    u'age': 12
})

# Update age and favorite color
frank_ref.update({
    u'age': 13,
    u'favorites.color': u'Red'
})
C++
// 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")},
});
  
Node.js
const initialData = {
  name: 'Frank',
  age: 12,
  favorites: {
    food: 'Pizza',
    color: 'Blue',
    subject: 'recess'
  }
};

// ...
const res = await db.collection('users').doc('Frank').update({
  age: 13,
  'favorites.color': 'Red'
});
Go
initialData := map[string]interface{}{
	"name": "Frank",
	"age":  12,
	"favorites": map[string]interface{}{
		"food":    "Pizza",
		"color":   "Blue",
		"subject": "recess",
	},
}

// ...

_, err := client.Collection("users").Doc("frank").Set(ctx, map[string]interface{}{
	"age": 13,
	"favorites": map[string]interface{}{
		"color": "Red",
	},
}, firestore.MergeAll)
if err != nil {
	// Handle any errors in an appropriate way, such as returning them.
	log.Printf("An error has occurred: %s", err)
}
PHP
// Create an initial document to update
$frankRef = $db->collection('users')->document('frank');
$frankRef->set([
    'name' => 'Frank',
    'favorites' => ['food' => 'Pizza', 'color' => 'Blue', 'subject' => 'Recess'],
    'age' => 12
]);

// Update age and favorite color
$frankRef->update([
    ['path' => 'age', 'value' => 13],
    ['path' => 'favorites.color', 'value' => 'Red']
]);
Unity
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.");
});
  
C#
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);
await frankDocRef.SetAsync(initialData);

// Update age and favorite color
Dictionary<string, object> updates = new Dictionary<string, object>
{
    { "Age", 13 },
    { "Favorites.Color", "Red" },
};

// Asynchronously update the document
await frankDocRef.UpdateAsync(updates);
Ruby
# Create an initial document to update
frank_ref = firestore.doc "#{collection_path}/frank"
frank_ref.set(
  name:      "Frank",
  favorites: {
    food:    "Pizza",
    color:   "Blue",
    subject: "Recess"
  },
  age:       12
)

# Update age and favorite color
frank_ref.update age: 13, "favorites.color": "Red"

La notación de puntos te permite actualizar un solo campo anidado sin reemplazar otro campo anidado. Si actualizas un campo anidado sin notación de puntos, reemplazarás todo el campo del mapa, por ejemplo:

Web

// 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
        }
 */

Actualiza elementos de un arreglo

Si tu documento contiene un campo de arreglo, puedes usar arrayUnion() y arrayRemove() para agregar y quitar elementos. Con arrayUnion(), se pueden agregar elementos a un arreglo, pero solo si aún no están presentes. arrayRemove() permite quitar todas las instancias de cada elemento dado.

Web
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")
});
Swift
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"])
])
Objective-C
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"]]
}];
  
Java
Android
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"));
Kotlin+KTX
Android
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"))
Java
DocumentReference washingtonRef = db.collection("cities").document("DC");

// Atomically add a new region to the "regions" array field.
ApiFuture<WriteResult> arrayUnion = washingtonRef.update("regions",
    FieldValue.arrayUnion("greater_virginia"));
System.out.println("Update time : " + arrayUnion.get());

// Atomically remove a region from the "regions" array field.
ApiFuture<WriteResult> arrayRm = washingtonRef.update("regions",
    FieldValue.arrayRemove("east_coast"));
System.out.println("Update time : " + arrayRm.get());
Python
city_ref = db.collection(u'cities').document(u'DC')

# Atomically add a new region to the 'regions' array field.
city_ref.update({u'regions': firestore.ArrayUnion([u'greater_virginia'])})

# // Atomically remove a region from the 'regions' array field.
city_ref.update({u'regions': firestore.ArrayRemove([u'east_coast'])})
C++
// This is not yet supported.
Node.js
const admin = require('firebase-admin');
// ...
const washingtonRef = db.collection('cities').doc('DC');

// Atomically add a new region to the "regions" array field.
const unionRes = await washingtonRef.update({
  regions: admin.firestore.FieldValue.arrayUnion('greater_virginia')
});
// Atomically remove a region from the "regions" array field.
const removeRes = await washingtonRef.update({
  regions: admin.firestore.FieldValue.arrayRemove('east_coast')
});
Go
// Not supported yet
PHP
$cityRef = $db->collection('cities')->document('DC');

// Atomically add a new region to the "regions" array field.
$cityRef->update([
    ['path' => 'regions', 'value' => FieldValue::arrayUnion(['greater_virginia'])]
]);

// Atomically remove a region from the "regions" array field.
$cityRef->update([
    ['path' => 'regions', 'value' => FieldValue::arrayRemove(['east_coast'])]
]);
Unity
// This is not yet supported in the Unity SDK
  
C#
DocumentReference washingtonRef = db.Collection("cities").Document("DC");

// Atomically add a new region to the "regions" array field.
await washingtonRef.UpdateAsync("Regions", FieldValue.ArrayUnion("greater_virginia"));

// Atomically remove a region from the "regions" array field.
await washingtonRef.UpdateAsync("Regions", FieldValue.ArrayRemove("east_coast"));
Ruby
// Not supported yet

Incrementa un valor numérico

Puedes aumentar o disminuir un valor de campo numérico como se muestra en el siguiente ejemplo. Una operación de incremento aumenta o disminuye el valor actual del campo según la cantidad dada. Si el campo no existe o si el valor actual del campo no es uno numérico, la operación configura el campo en el valor dado.

Web
var washingtonRef = db.collection('cities').doc('DC');

// Atomically increment the population of the city by 50.
washingtonRef.update({
    population: firebase.firestore.FieldValue.increment(50)
});
Swift
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))
])
Objective-C
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]
}];
  
Java
Android
DocumentReference washingtonRef = db.collection("cities").document("DC");

// Atomically increment the population of the city by 50.
washingtonRef.update("population", FieldValue.increment(50));
Kotlin+KTX
Android
val washingtonRef = db.collection("cities").document("DC")

// Atomically increment the population of the city by 50.
washingtonRef.update("population", FieldValue.increment(50))
Java
DocumentReference washingtonRef = db.collection("cities").document("DC");

// Atomically increment the population of the city by 50.
final ApiFuture<WriteResult> updateFuture = washingtonRef
    .update("population", FieldValue.increment(50));
Python
washington_ref = db.collection(u'cities').document(u'DC')

washington_ref.update({"population": firestore.Increment(50)})
C++
// This is not yet supported.
Node.js
const admin = require('firebase-admin');
// ...
const washingtonRef = db.collection('cities').doc('DC');

// Atomically increment the population of the city by 50.
const res = await washingtonRef.update({
  population: admin.firestore.FieldValue.increment(50)
});
Go
import (
	"context"
	"fmt"

	"cloud.google.com/go/firestore"
)

// updateDocumentIncrement increments the population of the city document in the
// cities collection by 50.
func updateDocumentIncrement(projectID, city string) error {
	// projectID := "my-project"

	ctx := context.Background()

	client, err := firestore.NewClient(ctx, projectID)
	if err != nil {
		return fmt.Errorf("firestore.NewClient: %v", err)
	}

	dc := client.Collection("cities").Doc(city)
	_, err = dc.Update(ctx, []firestore.Update{
		{Path: "population", Value: firestore.Increment(50)},
	})
	if err != nil {
		return fmt.Errorf("Update: %v", err)
	}

	return nil
}

PHP
$cityRef = $db->collection('cities')->document('DC');

// Atomically increment the population of the city by 50.
$cityRef->update([
    ['path' => 'regions', 'value' => FieldValue::increment(50)]
]);
Unity
// This is not yet supported in the Unity SDK.
  
C#
DocumentReference washingtonRef = db.Collection("cities").Document("DC");

// Atomically increment the population of the city by 50.
await washingtonRef.UpdateAsync("Regions", FieldValue.Increment(50));
Ruby
city_ref = firestore.doc "#{collection_path}/DC"
city_ref.update population: firestore.field_increment(50)

Las operaciones de incremento son útiles para implementar contadores, pero ten en cuenta que puedes actualizar un documento individual solo una vez por segundo. Si necesitas actualizar tu contador por encima de esta frecuencia, consulta la página Contadores distribuidos.