Cloud Firestore proporciona una potente función de consulta para especificar
los documentos que quieres recuperar de una colección o un grupo de colecciones. Estas consultas también se pueden usar con get()
o addSnapshotListener()
, como se describe en los artículos sobre cómo obtener datos y obtener actualizaciones en tiempo real.
Datos de ejemplo
Para comenzar, escribe algunos datos sobre ciudades para que podamos ver las distintas maneras de leerlos:
Web version 9
import { collection, doc, setDoc } from "firebase/firestore"; const citiesRef = collection(db, "cities"); await setDoc(doc(citiesRef, "SF"), { name: "San Francisco", state: "CA", country: "USA", capital: false, population: 860000, regions: ["west_coast", "norcal"] }); await setDoc(doc(citiesRef, "LA"), { name: "Los Angeles", state: "CA", country: "USA", capital: false, population: 3900000, regions: ["west_coast", "socal"] }); await setDoc(doc(citiesRef, "DC"), { name: "Washington, D.C.", state: null, country: "USA", capital: true, population: 680000, regions: ["east_coast"] }); await setDoc(doc(citiesRef, "TOK"), { name: "Tokyo", state: null, country: "Japan", capital: true, population: 9000000, regions: ["kanto", "honshu"] }); await setDoc(doc(citiesRef, "BJ"), { name: "Beijing", state: null, country: "China", capital: true, population: 21500000, regions: ["jingjinji", "hebei"] });
Web version 8
var citiesRef = db.collection("cities"); citiesRef.doc("SF").set({ name: "San Francisco", state: "CA", country: "USA", capital: false, population: 860000, regions: ["west_coast", "norcal"] }); citiesRef.doc("LA").set({ name: "Los Angeles", state: "CA", country: "USA", capital: false, population: 3900000, regions: ["west_coast", "socal"] }); citiesRef.doc("DC").set({ name: "Washington, D.C.", state: null, country: "USA", capital: true, population: 680000, regions: ["east_coast"] }); citiesRef.doc("TOK").set({ name: "Tokyo", state: null, country: "Japan", capital: true, population: 9000000, regions: ["kanto", "honshu"] }); citiesRef.doc("BJ").set({ name: "Beijing", state: null, country: "China", capital: true, population: 21500000, regions: ["jingjinji", "hebei"] });
Swift
let citiesRef = db.collection("cities") citiesRef.document("SF").setData([ "name": "San Francisco", "state": "CA", "country": "USA", "capital": false, "population": 860000, "regions": ["west_coast", "norcal"] ]) citiesRef.document("LA").setData([ "name": "Los Angeles", "state": "CA", "country": "USA", "capital": false, "population": 3900000, "regions": ["west_coast", "socal"] ]) citiesRef.document("DC").setData([ "name": "Washington D.C.", "country": "USA", "capital": true, "population": 680000, "regions": ["east_coast"] ]) citiesRef.document("TOK").setData([ "name": "Tokyo", "country": "Japan", "capital": true, "population": 9000000, "regions": ["kanto", "honshu"] ]) citiesRef.document("BJ").setData([ "name": "Beijing", "country": "China", "capital": true, "population": 21500000, "regions": ["jingjinji", "hebei"] ])
Objective‑C
FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"]; [[citiesRef documentWithPath:@"SF"] setData:@{ @"name": @"San Francisco", @"state": @"CA", @"country": @"USA", @"capital": @(NO), @"population": @860000, @"regions": @[@"west_coast", @"norcal"] }]; [[citiesRef documentWithPath:@"LA"] setData:@{ @"name": @"Los Angeles", @"state": @"CA", @"country": @"USA", @"capital": @(NO), @"population": @3900000, @"regions": @[@"west_coast", @"socal"] }]; [[citiesRef documentWithPath:@"DC"] setData:@{ @"name": @"Washington D.C.", @"country": @"USA", @"capital": @(YES), @"population": @680000, @"regions": @[@"east_coast"] }]; [[citiesRef documentWithPath:@"TOK"] setData:@{ @"name": @"Tokyo", @"country": @"Japan", @"capital": @(YES), @"population": @9000000, @"regions": @[@"kanto", @"honshu"] }]; [[citiesRef documentWithPath:@"BJ"] setData:@{ @"name": @"Beijing", @"country": @"China", @"capital": @(YES), @"population": @21500000, @"regions": @[@"jingjinji", @"hebei"] }];
Kotlin+KTX
val cities = db.collection("cities") val data1 = hashMapOf( "name" to "San Francisco", "state" to "CA", "country" to "USA", "capital" to false, "population" to 860000, "regions" to listOf("west_coast", "norcal") ) cities.document("SF").set(data1) val data2 = hashMapOf( "name" to "Los Angeles", "state" to "CA", "country" to "USA", "capital" to false, "population" to 3900000, "regions" to listOf("west_coast", "socal") ) cities.document("LA").set(data2) val data3 = hashMapOf( "name" to "Washington D.C.", "state" to null, "country" to "USA", "capital" to true, "population" to 680000, "regions" to listOf("east_coast") ) cities.document("DC").set(data3) val data4 = hashMapOf( "name" to "Tokyo", "state" to null, "country" to "Japan", "capital" to true, "population" to 9000000, "regions" to listOf("kanto", "honshu") ) cities.document("TOK").set(data4) val data5 = hashMapOf( "name" to "Beijing", "state" to null, "country" to "China", "capital" to true, "population" to 21500000, "regions" to listOf("jingjinji", "hebei") ) cities.document("BJ").set(data5)
Java
CollectionReference cities = db.collection("cities"); Map<String, Object> data1 = new HashMap<>(); data1.put("name", "San Francisco"); data1.put("state", "CA"); data1.put("country", "USA"); data1.put("capital", false); data1.put("population", 860000); data1.put("regions", Arrays.asList("west_coast", "norcal")); cities.document("SF").set(data1); Map<String, Object> data2 = new HashMap<>(); data2.put("name", "Los Angeles"); data2.put("state", "CA"); data2.put("country", "USA"); data2.put("capital", false); data2.put("population", 3900000); data2.put("regions", Arrays.asList("west_coast", "socal")); cities.document("LA").set(data2); Map<String, Object> data3 = new HashMap<>(); data3.put("name", "Washington D.C."); data3.put("state", null); data3.put("country", "USA"); data3.put("capital", true); data3.put("population", 680000); data3.put("regions", Arrays.asList("east_coast")); cities.document("DC").set(data3); Map<String, Object> data4 = new HashMap<>(); data4.put("name", "Tokyo"); data4.put("state", null); data4.put("country", "Japan"); data4.put("capital", true); data4.put("population", 9000000); data4.put("regions", Arrays.asList("kanto", "honshu")); cities.document("TOK").set(data4); Map<String, Object> data5 = new HashMap<>(); data5.put("name", "Beijing"); data5.put("state", null); data5.put("country", "China"); data5.put("capital", true); data5.put("population", 21500000); data5.put("regions", Arrays.asList("jingjinji", "hebei")); cities.document("BJ").set(data5);
Dart
final cities = db.collection("cities"); final data1 = <String, dynamic>{ "name": "San Francisco", "state": "CA", "country": "USA", "capital": false, "population": 860000, "regions": ["west_coast", "norcal"] }; cities.doc("SF").set(data1); final data2 = <String, dynamic>{ "name": "Los Angeles", "state": "CA", "country": "USA", "capital": false, "population": 3900000, "regions": ["west_coast", "socal"], }; cities.doc("LA").set(data2); final data3 = <String, dynamic>{ "name": "Washington D.C.", "state": null, "country": "USA", "capital": true, "population": 680000, "regions": ["east_coast"] }; cities.doc("DC").set(data3); final data4 = <String, dynamic>{ "name": "Tokyo", "state": null, "country": "Japan", "capital": true, "population": 9000000, "regions": ["kanto", "honshu"] }; cities.doc("TOK").set(data4); final data5 = <String, dynamic>{ "name": "Beijing", "state": null, "country": "China", "capital": true, "population": 21500000, "regions": ["jingjinji", "hebei"], }; cities.doc("BJ").set(data5);
Java
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}\ )' )
cities_ref = db.collection(u'cities') cities_ref.document(u'BJ').set( City(u'Beijing', None, u'China', True, 21500000, [u'hebei']).to_dict()) cities_ref.document(u'SF').set( City(u'San Francisco', u'CA', u'USA', False, 860000, [u'west_coast', u'norcal']).to_dict()) cities_ref.document(u'LA').set( City(u'Los Angeles', u'CA', u'USA', False, 3900000, [u'west_coast', u'socal']).to_dict()) cities_ref.document(u'DC').set( City(u'Washington D.C.', None, u'USA', True, 680000, [u'east_coast']).to_dict()) cities_ref.document(u'TOK').set( City(u'Tokyo', None, u'Japan', True, 9000000, [u'kanto', u'honshu']).to_dict())
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}\ )"
cities_ref = db.collection("cities") await cities_ref.document("BJ").set( City("Beijing", None, "China", True, 21500000, ["hebei"]).to_dict() ) await cities_ref.document("SF").set( City( "San Francisco", "CA", "USA", False, 860000, ["west_coast", "norcal"] ).to_dict() ) await cities_ref.document("LA").set( City( "Los Angeles", "CA", "USA", False, 3900000, ["west_coast", "socal"] ).to_dict() ) await cities_ref.document("DC").set( City("Washington D.C.", None, "USA", True, 680000, ["east_coast"]).to_dict() ) await cities_ref.document("TOK").set( City("Tokyo", None, "Japan", True, 9000000, ["kanto", "honshu"]).to_dict() )
C++
CollectionReference cities = db->Collection("cities"); cities.Document("SF").Set({ {"name", FieldValue::String("San Francisco")}, {"state", FieldValue::String("CA")}, {"country", FieldValue::String("USA")}, {"capital", FieldValue::Boolean(false)}, {"population", FieldValue::Integer(860000)}, {"regions", FieldValue::Array({FieldValue::String("west_coast"), FieldValue::String("norcal")})}, }); cities.Document("LA").Set({ {"name", FieldValue::String("Los Angeles")}, {"state", FieldValue::String("CA")}, {"country", FieldValue::String("USA")}, {"capital", FieldValue::Boolean(false)}, {"population", FieldValue::Integer(3900000)}, {"regions", FieldValue::Array({FieldValue::String("west_coast"), FieldValue::String("socal")})}, }); cities.Document("DC").Set({ {"name", FieldValue::String("Washington D.C.")}, {"state", FieldValue::Null()}, {"country", FieldValue::String("USA")}, {"capital", FieldValue::Boolean(true)}, {"population", FieldValue::Integer(680000)}, {"regions", FieldValue::Array({FieldValue::String("east_coast")})}, }); cities.Document("TOK").Set({ {"name", FieldValue::String("Tokyo")}, {"state", FieldValue::Null()}, {"country", FieldValue::String("Japan")}, {"capital", FieldValue::Boolean(true)}, {"population", FieldValue::Integer(9000000)}, {"regions", FieldValue::Array({FieldValue::String("kanto"), FieldValue::String("honshu")})}, }); cities.Document("BJ").Set({ {"name", FieldValue::String("Beijing")}, {"state", FieldValue::Null()}, {"country", FieldValue::String("China")}, {"capital", FieldValue::Boolean(true)}, {"population", FieldValue::Integer(21500000)}, {"regions", FieldValue::Array({FieldValue::String("jingjinji"), FieldValue::String("hebei")})}, });
Node.js
Go
PHP
Unity
CollectionReference citiesRef = db.Collection("cities"); citiesRef.Document("SF").SetAsync(new Dictionary<string, object>(){ { "Name", "San Francisco" }, { "State", "CA" }, { "Country", "USA" }, { "Capital", false }, { "Population", 860000 }, { "Regions", new ArrayList{"west_coast", "norcal"} } }); citiesRef.Document("LA").SetAsync(new Dictionary<string, object>(){ { "Name", "Los Angeles" }, { "State", "CA" }, { "Country", "USA" }, { "Capital", false }, { "Population", 3900000 }, { "Regions", new ArrayList{"west_coast", "socal"} } }); citiesRef.Document("DC").SetAsync(new Dictionary<string, object>(){ { "Name", "Washington D.C." }, { "State", null }, { "Country", "USA" }, { "Capital", true }, { "Population", 680000 }, { "Regions", new ArrayList{"east_coast"} } }); citiesRef.Document("TOK").SetAsync(new Dictionary<string, object>(){ { "Name", "Tokyo" }, { "State", null }, { "Country", "Japan" }, { "Capital", true }, { "Population", 9000000 }, { "Regions", new ArrayList{"kanto", "honshu"} } }); citiesRef.Document("BJ").SetAsync(new Dictionary<string, object>(){ { "Name", "Beijing" }, { "State", null }, { "Country", "China" }, { "Capital", true }, { "Population", 21500000 }, { "Regions", new ArrayList{"jingjinji", "hebei"} } });
C#
Ruby
Consultas simples
La siguiente consulta muestra todas las ciudades con el estado CA
:
Web version 9
// Create a reference to the cities collection import { collection, query, where } from "firebase/firestore"; const citiesRef = collection(db, "cities"); // Create a query against the collection. const q = query(citiesRef, where("state", "==", "CA"));
Web version 8
// Create a reference to the cities collection var citiesRef = db.collection("cities"); // Create a query against the collection. var query = citiesRef.where("state", "==", "CA");
Swift
// Create a reference to the cities collection let citiesRef = db.collection("cities") // Create a query against the collection. let query = citiesRef.whereField("state", isEqualTo: "CA")
Objective‑C
// Create a reference to the cities collection FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"]; // Create a query against the collection. FIRQuery *query = [citiesRef queryWhereField:@"state" isEqualTo:@"CA"];
Kotlin+KTX
// Create a reference to the cities collection val citiesRef = db.collection("cities") // Create a query against the collection. val query = citiesRef.whereEqualTo("state", "CA")
Java
// Create a reference to the cities collection CollectionReference citiesRef = db.collection("cities"); // Create a query against the collection. Query query = citiesRef.whereEqualTo("state", "CA");
Dart
// Create a reference to the cities collection final citiesRef = db.collection("cities"); // Create a query against the collection. final query = citiesRef.where("state", isEqualTo: "CA");
Java
Python
Python
C++
CollectionReference cities_ref = db->Collection("cities"); // Create a query against the collection. Query query_ca = cities_ref.WhereEqualTo("state", FieldValue::String("CA"));
Node.js
Go
PHP
Unity
CollectionReference citiesRef = db.Collection("cities"); Query query = citiesRef.WhereEqualTo("State", "CA"); query.GetSnapshotAsync().ContinueWithOnMainThread((querySnapshotTask) => { foreach (DocumentSnapshot documentSnapshot in querySnapshotTask.Result.Documents) { Debug.Log(String.Format("Document {0} returned by query State=CA", documentSnapshot.Id)); } });
C#
Ruby
La siguiente consulta muestra todas las capitales:
Web version 9
import { collection, query, where } from "firebase/firestore"; const citiesRef = collection(db, "cities"); const q = query(citiesRef, where("capital", "==", true));
Web version 8
var citiesRef = db.collection("cities"); var query = citiesRef.where("capital", "==", true);
Swift
let capitalCities = db.collection("cities").whereField("capital", isEqualTo: true)
Objective‑C
FIRQuery *capitalCities = [[self.db collectionWithPath:@"cities"] queryWhereField:@"capital" isEqualTo:@YES];
Kotlin+KTX
val capitalCities = db.collection("cities").whereEqualTo("capital", true)
Java
Query capitalCities = db.collection("cities").whereEqualTo("capital", true);
Dart
final capitalcities = db.collection("cities").where("capital", isEqualTo: true);
Java
Python
Python
C++
Query capital_cities = db->Collection("cities").WhereEqualTo( "capital", FieldValue::Boolean(true));
Node.js
Go
PHP
Unity
CollectionReference citiesRef = db.Collection("cities"); Query query = citiesRef.WhereEqualTo("Capital", true); query.GetSnapshotAsync().ContinueWithOnMainThread((querySnapshotTask) => { foreach (DocumentSnapshot documentSnapshot in querySnapshotTask.Result.Documents) { Debug.Log(String.Format("Document {0} returned by query Capital=true", documentSnapshot.Id)); } });
C#
Ruby
Ejecuta una consulta
Después de crear un objeto de consulta, usa la función get()
para recuperar los resultados:
Web version 9
import { collection, query, where, getDocs } from "firebase/firestore"; const q = query(collection(db, "cities"), where("capital", "==", true)); const querySnapshot = await getDocs(q); querySnapshot.forEach((doc) => { // doc.data() is never undefined for query doc snapshots console.log(doc.id, " => ", doc.data()); });
Web version 8
db.collection("cities").where("capital", "==", true) .get() .then((querySnapshot) => { querySnapshot.forEach((doc) => { // doc.data() is never undefined for query doc snapshots console.log(doc.id, " => ", doc.data()); }); }) .catch((error) => { console.log("Error getting documents: ", error); });
Swift
db.collection("cities").whereField("capital", isEqualTo: true) .getDocuments() { (querySnapshot, err) in if let err = err { print("Error getting documents: \(err)") } else { for document in querySnapshot!.documents { print("\(document.documentID) => \(document.data())") } } }
Objective‑C
[[[self.db collectionWithPath:@"cities"] queryWhereField:@"capital" isEqualTo:@(YES)] getDocumentsWithCompletion:^(FIRQuerySnapshot *snapshot, NSError *error) { if (error != nil) { NSLog(@"Error getting documents: %@", error); } else { for (FIRDocumentSnapshot *document in snapshot.documents) { NSLog(@"%@ => %@", document.documentID, document.data); } } }];
Kotlin+KTX
db.collection("cities") .whereEqualTo("capital", true) .get() .addOnSuccessListener { documents -> for (document in documents) { Log.d(TAG, "${document.id} => ${document.data}") } } .addOnFailureListener { exception -> Log.w(TAG, "Error getting documents: ", exception) }
Java
db.collection("cities") .whereEqualTo("capital", true) .get() .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() { @Override public void onComplete(@NonNull Task<QuerySnapshot> task) { if (task.isSuccessful()) { for (QueryDocumentSnapshot document : task.getResult()) { Log.d(TAG, document.getId() + " => " + document.getData()); } } else { Log.d(TAG, "Error getting documents: ", task.getException()); } } });
Dart
db.collection("cities").where("capital", isEqualTo: true).get().then( (querySnapshot) { print("Successfully completed"); for (var docSnapshot in querySnapshot.docs) { print('${docSnapshot.id} => ${docSnapshot.data()}'); } }, onError: (e) => print("Error completing: $e"), );
Java
Python
Python
C++
db->Collection("cities") .WhereEqualTo("capital", FieldValue::Boolean(true)) .Get() .OnCompletion([](const Future<QuerySnapshot>& future) { if (future.error() == Error::kErrorOk) { for (const DocumentSnapshot& document : future.result()->documents()) { std::cout << document << std::endl; } } else { std::cout << "Error getting documents: " << future.error_message() << std::endl; } });
Node.js
Go
PHP
PHP
Para obtener más información sobre la instalación y creación de un cliente de Cloud Firestore, consulta las bibliotecas cliente de Cloud Firestore.
Unity
Query capitalQuery = db.Collection("cities").WhereEqualTo("Capital", true); capitalQuery.GetSnapshotAsync().ContinueWithOnMainThread(task => { QuerySnapshot capitalQuerySnapshot = task.Result; foreach (DocumentSnapshot documentSnapshot in capitalQuerySnapshot.Documents) { Debug.Log(String.Format("Document data for {0} document:", documentSnapshot.Id)); Dictionary<string, object> city = documentSnapshot.ToDictionary(); foreach (KeyValuePair<string, object> pair in city) { Debug.Log(String.Format("{0}: {1}", pair.Key, pair.Value)); } // Newline to separate entries Debug.Log(""); }; });
C#
Ruby
Consulta cómo obtener datos para saber más sobre cómo recuperar resultados de consultas. También puedes agregar un objeto de escucha a una consulta para obtener los resultados actuales y detectar actualizaciones futuras.
Operadores de consultas
El método where()
usa tres parámetros: un campo para filtrar, una operación de comparación y un valor. Cloud Firestore admite los siguientes operadores de comparación:
<
menor que<=
menor o igual que==
igual que>
mayor que>=
mayor que o igual que!=
no igual aarray-contains
array-contains-any
in
not-in
Por ejemplo:
Web version 9
const stateQuery = query(citiesRef, where("state", "==", "CA")); const populationQuery = query(citiesRef, where("population", "<", 100000)); const nameQuery = query(citiesRef, where("name", ">=", "San Francisco"));
Web version 8
const stateQuery = citiesRef.where("state", "==", "CA"); const populationQuery = citiesRef.where("population", "<", 100000); const nameQuery = citiesRef.where("name", ">=", "San Francisco");
Swift
let stateQuery = citiesRef.whereField("state", isEqualTo: "CA") let populationQuery = citiesRef.whereField("population", isLessThan: 100000) let nameQuery = citiesRef.whereField("name", isGreaterThanOrEqualTo: "San Francisco")
Objective‑C
FIRQuery *stateQuery = [citiesRef queryWhereField:@"state" isEqualTo:@"CA"]; FIRQuery *populationQuery = [citiesRef queryWhereField:@"population" isLessThan:@100000]; FIRQuery *nameQuery = [citiesRef queryWhereField:@"name" isGreaterThanOrEqualTo:@"San Francisco"];
Kotlin+KTX
val stateQuery = citiesRef.whereEqualTo("state", "CA") val populationQuery = citiesRef.whereLessThan("population", 100000) val nameQuery = citiesRef.whereGreaterThanOrEqualTo("name", "San Francisco")
Java
Query stateQuery = citiesRef.whereEqualTo("state", "CA"); Query populationQuery = citiesRef.whereLessThan("population", 100000); Query nameQuery = citiesRef.whereGreaterThanOrEqualTo("name", "San Francisco");
Dart
final citiesRef = db.collection("cities"); final stateQuery = citiesRef.where("state", isEqualTo: "CA"); final populationQuery = citiesRef.where("population", isLessThan: 100000); final nameQuery = citiesRef.where("name", isEqualTo: "San Francisco");
Java
Python
Python
C++
cities_ref.WhereEqualTo("state", FieldValue::String("CA")); cities_ref.WhereLessThan("population", FieldValue::Integer(100000)); cities_ref.WhereGreaterThanOrEqualTo("name", FieldValue::String("San Francisco"));
Node.js
Go
PHP
Unity
Query stateQuery = citiesRef.WhereEqualTo("State", "CA"); Query populationQuery = citiesRef.WhereGreaterThan("Population", 1000000); Query nameQuery = citiesRef.WhereGreaterThanOrEqualTo("Name", "San Francisco");
C#
Ruby
No igual (!=
)
Usa el operador no igual (!=
) para mostrar documentos en los que exista el campo especificado
y no coincida con el valor de comparación. Por ejemplo:
Web version 9
const notCapitalQuery = query(citiesRef, where("capital", "!=", false));
Web version 8
citiesRef.where("capital", "!=", false);
Swift
let notEqualQuery = citiesRef.whereField("capital", isNotEqualTo: false)
Objective‑C
query = [citiesRef queryWhereField:@"capital" isNotEqualTo:@NO];
Kotlin+KTX
val notCapitalQuery = citiesRef.whereNotEqualTo("capital", false)
Java
Query notCapitalQuery = citiesRef.whereNotEqualTo("capital", false);
Dart
final citiesRef = db.collection("cities"); final notCapitals = citiesRef.where("capital", isNotEqualTo: true);
Java
Python
// Snippet not yet available
C++
// Snippet not yet available
Node.js
Go
// Snippet not yet available
PHP
Unity
// Snippet not yet available
C#
// Snippet not yet available
Ruby
Esta consulta muestra todos los documentos de city
en los que existe el campo capital
con un valor distinto de false
o null
. Esto incluye los documentos de city
en los que el valor del campo capital
es igual a true
o a cualquier valor no booleano además de null
.
Esta consulta no muestra los documentos de city
en los que no existe el campo capital
. Las consultas no igual (!=
) y not-in
excluyen los documentos en los que no existe el campo especificado.
Un campo existe cuando se configura con cualquier valor, incluida una string vacía (""
), null
y NaN
(no un número). Ten en cuenta que los valores del campo null
no coinciden con las cláusulas !=
porque x != null
se evalúa como undefined
.
Limitaciones
Ten en cuenta las siguientes limitaciones de las consultas !=
:
- Solo los documentos en los que existe el campo especificado pueden coincidir con la consulta.
- No puedes combinar
not-in
y!=
en una consulta compuesta. - En una consulta compuesta, las comparaciones de intervalo (
<
,<=
,>
y>=
) y desigualdad (!=
ynot-in
) deben aplicar filtros en el mismo campo.
Pertenencia a un array
Puedes usar el operador array-contains
para filtrar en función de los valores del array. Por ejemplo:
Web version 9
import { query, where } from "firebase/firestore"; const q = query(citiesRef, where("regions", "array-contains", "west_coast"));
Web version 8
citiesRef.where("regions", "array-contains", "west_coast");
Swift
citiesRef .whereField("regions", arrayContains: "west_coast")
Objective‑C
[citiesRef queryWhereField:@"state" arrayContains:@"west_coast"];
Kotlin+KTX
val citiesRef = db.collection("cities") citiesRef.whereArrayContains("regions", "west_coast")
Java
CollectionReference citiesRef = db.collection("cities"); citiesRef.whereArrayContains("regions", "west_coast");
Dart
final citiesRef = db.collection("cities"); final westCoastcities = citiesRef.where("regions", arrayContains: "west_coast");
Java
Python
Python
C++
CollectionReference cities_ref = db->Collection("cities"); cities_ref.WhereArrayContains("region", FieldValue::String("west_coast"));
Node.js
Go
PHP
Unity
CollectionReference citiesRef = db.Collection("cities"); Query arrayContainsQuery = citiesRef.WhereArrayContains("region", "west_coast");
C#
Ruby
Esta consulta muestra todos los documentos de city
en los que el campo regions
es un array que contiene west_coast
. Si el array tiene múltiples instancias del valor que
consultaste, el documento se incluye en los resultados solo una vez.
Puedes usar como máximo una cláusula array-contains
por consulta. No puedes combinar array-contains
con array-contains-any
.
in
, not-in
y array-contains-any
Usa el operador in
para combinar hasta 10 cláusulas de igualdad (==
) en el mismo campo con un OR
lógico. Una consulta in
muestra documentos en los que el campo dado coincide con cualquiera de los valores de comparación. Por ejemplo:
Web version 9
import { query, where } from "firebase/firestore"; const q = query(citiesRef, where('country', 'in', ['USA', 'Japan']));
Web version 8
citiesRef.where('country', 'in', ['USA', 'Japan']);
Swift
let citiesRef = db.collection("cities") citiesRef.whereField("country", in: ["USA", "Japan"])
Objective‑C
FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"]; [citiesRef queryWhereField:@"country" in:@[@"USA", @"Japan"]];
Kotlin+KTX
val citiesRef = db.collection("cities") citiesRef.whereIn("country", listOf("USA", "Japan"))
Java
CollectionReference citiesRef = db.collection("cities"); citiesRef.whereIn("country", Arrays.asList("USA", "Japan"));
Dart
final citiesRef = db.collection("cities"); final cities = citiesRef.where("country", whereIn: ["USA", "Japan"]);
Java
Python
Python
C++
CollectionReference cities_ref = db->Collection("cities"); cities_ref.WhereIn("country", std::vector<FieldValue> { FieldValue::String("USA"), FieldValue::String("Japan") });
Node.js
Go
PHP
Unity
CollectionReference citiesRef = db.Collection("cities"); ListcountriesList = new List<object>() {"USA", "Japan"}; Query whereInQuery = citiesRef.WhereIn("country", countriesList);
C#
Ruby
Esta consulta muestra todos los documentos city
en los que el campo country
se configura como USA
o Japan
. A partir de los datos de ejemplo, se incluyen los documentos SF
, LA
, DC
y TOK
.
not-in
Usa el operador not-in
para combinar hasta 10 cláusulas no igual (!=
) en el mismo campo con un AND
lógico. Una consulta not-in
muestra documentos en los que existe el campo especificado, no es null
y no coincide con ninguno de los valores de comparación. Por ejemplo:
Web version 9
import { query, where } from "firebase/firestore"; const q = query(citiesRef, where('country', 'not-in', ['USA', 'Japan']));
Web version 8
citiesRef.where('country', 'not-in', ['USA', 'Japan']);
Swift
citiesRef.whereField("country", notIn: ["USA", "Japan"])
Objective‑C
[citiesRef queryWhereField:@"country" notIn:@[@"USA", @"Japan"]];
Kotlin+KTX
citiesRef.whereNotIn("country", listOf("USA", "Japan"))
Java
citiesRef.whereNotIn("country", Arrays.asList("USA", "Japan"));
Dart
final citiesRef = db.collection("cities"); final cities = citiesRef.where("country", whereNotIn: ["USA", "Japan"]);
Java
Python
// Snippet not yet available
C++
cities_ref.WhereNotIn("country", std::vector<FieldValue> { FieldValue::String("USA"), FieldValue::String("Japan") });
Node.js
Go
// Snippet not yet available
PHP
Unity
// Snippet not yet available
C#
// Snippet not yet available
Ruby
Esta consulta muestra todos los documentos city
en los que existe el campo country
y no se
definió como USA
, Japan
ni null
. A partir de los datos de ejemplo, se incluyen los documentos London
y Hong Kong
.
Las consultas not-in
excluyen los documentos en los que no existe el campo especificado. Un campo existe cuando se configura con cualquier valor, incluida una string vacía (""
), null
y NaN
(no un número). Ten en cuenta que x != null
se evalúa como undefined
. Una consulta not-in
con null
como uno de los valores de comparación no coincide con ningún documento.
array-contains-any
Del mismo modo, usa el operador array-contains-any
para combinar hasta 10 cláusulas array-contains
en el mismo campo con un OR
lógico. Una consulta
array-contains-any
muestra documentos en los que el campo dado es un array
que contiene uno o más de los valores de comparación:
Web version 9
import { query, where } from "firebase/firestore"; const q = query(citiesRef, where('regions', 'array-contains-any', ['west_coast', 'east_coast']));
Web version 8
citiesRef.where('regions', 'array-contains-any', ['west_coast', 'east_coast']);
Swift
let citiesRef = db.collection("cities") citiesRef.whereField("regions", arrayContainsAny: ["west_coast", "east_coast"])
Objective‑C
FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"]; [citiesRef queryWhereField:@"regions" arrayContainsAny:@[@"west_coast", @"east_coast"]];
Kotlin+KTX
val citiesRef = db.collection("cities") citiesRef.whereArrayContainsAny("regions", listOf("west_coast", "east_coast"))
Java
CollectionReference citiesRef = db.collection("cities"); citiesRef.whereArrayContainsAny("regions", Arrays.asList("west_coast", "east_coast"));
Dart
final citiesRef = db.collection("cities"); final cities = citiesRef .where("regions", arrayContainsAny: ["west_coast", "east_coast"]);
Java
Python
Python
C++
CollectionReference cities_ref = db->Collection("cities"); cities_ref.WhereArrayContainsAny("region", std::vector<FieldValue> { FieldValue::String("west_coast"), FieldValue::String("east_coast") });
Node.js
Go
PHP
Unity
CollectionReference citiesRef = db.Collection("cities"); ListregionsList = new List<object>() {"west_coast", "east_coast"}; Query arrayContainsAnyQuery = citiesRef.WhereArrayContainsAny("regions", regionsList);
C#
Ruby
Esta consulta muestra todos los documentos de city en los que el campo regions
es un array que contiene west_coast
o east_coast
. A partir de los datos de ejemplo, se incluyen los documentos SF
, LA
y DC
.
Se deducen los resultados de array-contains-any
. Aunque el campo de array de un documento coincida con más de uno de los valores de comparación, el conjunto de resultados solo incluye ese documento una vez.
array-contains-any
siempre filtra por el tipo de datos del array. Por ejemplo, la consulta anterior no mostraría un documento de city en el que, en lugar de un array, el campo regions
sea la string west_coast
.
Puedes usar un valor de array como un valor de comparación para in
, pero a diferencia de array-contains-any
, la cláusula coincide exactamente con los valores, el orden y la longitud del array. Por ejemplo:
Web version 9
import { query, where } from "firebase/firestore"; const q = query(citiesRef, where('regions', 'in', [['west_coast', 'east_coast']]));
Web version 8
citiesRef.where('regions', 'in', [['west_coast', 'east_coast']]);
Swift
citiesRef.whereField("regions", in: [["west_coast"], ["east_coast"]]);
Objective‑C
[citiesRef queryWhereField:@"regions" in:@[@[@"west_coast"], @[@"east_coast"]]];
Kotlin+KTX
citiesRef.whereIn("regions", listOf(arrayOf("west_coast"), arrayOf("east_coast")))
Java
citiesRef.whereIn("regions", Arrays.asList(new String[]{"west_coast"}, new String[]{"east_coast"}));
Dart
final citiesRef = db.collection("cities"); final cities = citiesRef.where("regions", whereIn: [ ["west_coast"], ["east_coast"] ]);
Java
Python
Python
C++
cities_ref.WhereIn("region", std::vector<FieldValue> { FieldValue::String("west_coast"), FieldValue::String("east_coast") });
Node.js
Go
PHP
Unity
// Not yet supported in the Unity SDK
C#
Ruby
Esta consulta muestra todos los documentos de city en los que el campo regions
es un array que contiene exactamente un elemento de west_coast
o east_coast
.
A partir de los datos de ejemplo, solo el documento DC
califica con su campo regions
de ["east_coast"]
. Sin embargo, el documento SF
no coincide porque su campo regions
es ["west_coast", "norcal"]
.
Limitaciones
Ten en cuenta las siguientes limitaciones de in
, not-in
, y array-contains-any
:
in
,not-in
yarray-contains-any
admiten hasta 10 valores de comparación.- Puedes usar como máximo una cláusula
array-contains
por consulta. No puedes combinararray-contains
conarray-contains-any
. - Puedes usar como máximo una cláusula
in
,not-in
oarray-contains-any
por consulta. No puedes combinar estos operadores en la misma consulta. - No puedes combinar
not-in
con no es igual a!=
. - No puedes ordenar tu consulta por un campo incluido en una cláusula de igualdad (
==
) oin
.
Consultas compuestas
Puedes encadenar múltiples métodos de operadores de igualdad (==
o array-contains
) para
crear consultas más específicas (AND
lógico). Sin embargo, debes crear un
índice compuesto para combinar los operadores de igualdad con los operadores de desigualdad
<
, <=
, >
y !=
.
Web version 9
import { query, where } from "firebase/firestore"; const q1 = query(citiesRef, where("state", "==", "CO"), where("name", "==", "Denver")); const q2 = query(citiesRef, where("state", "==", "CA"), where("population", "<", 1000000));
Web version 8
const q1 = citiesRef.where("state", "==", "CO").where("name", "==", "Denver"); const q2 = citiesRef.where("state", "==", "CA").where("population", "<", 1000000);
Swift
citiesRef .whereField("state", isEqualTo: "CO") .whereField("name", isEqualTo: "Denver") citiesRef .whereField("state", isEqualTo: "CA") .whereField("population", isLessThan: 1000000)
Objective‑C
[[citiesRef queryWhereField:@"state" isEqualTo:@"CO"] queryWhereField:@"name" isGreaterThanOrEqualTo:@"Denver"]; [[citiesRef queryWhereField:@"state" isEqualTo:@"CA"] queryWhereField:@"population" isLessThan:@1000000];
Kotlin+KTX
citiesRef.whereEqualTo("state", "CO").whereEqualTo("name", "Denver") citiesRef.whereEqualTo("state", "CA").whereLessThan("population", 1000000)
Java
citiesRef.whereEqualTo("state", "CO").whereEqualTo("name", "Denver"); citiesRef.whereEqualTo("state", "CA").whereLessThan("population", 1000000);
Dart
final citiesRef = db.collection("cities"); citiesRef .where("state", isEqualTo: "CO") .where("name", isEqualTo: "Denver"); citiesRef .where("state", isEqualTo: "CA") .where("population", isLessThan: 1000000);
Java
Python
Python
C++
cities_ref.WhereEqualTo("state", FieldValue::String("CO")) .WhereEqualTo("name", FieldValue::String("Denver")); cities_ref.WhereEqualTo("state", FieldValue::String("CA")) .WhereLessThan("population", FieldValue::Integer(1000000));
Node.js
Go
PHP
Unity
Query chainedQuery = citiesRef .WhereEqualTo("State", "CA") .WhereEqualTo("Name", "San Francisco");
C#
Ruby
Puedes realizar comparaciones de rango (<
, <=
, >
, >=
) o no igual (!=
) solo en un campo único y puedes incluir como máximo una cláusula array-contains
o array-contains-any
en una consulta compuesta:
Válido: Filtros de rango en solo un campo
Web version 9
import { query, where } from "firebase/firestore"; const q1 = query(citiesRef, where("state", ">=", "CA"), where("state", "<=", "IN")); const q2 = query(citiesRef, where("state", "==", "CA"), where("population", ">", 1000000));
Web version 8
const q1 = citiesRef.where("state", ">=", "CA").where("state", "<=", "IN"); const q2 = citiesRef.where("state", "==", "CA").where("population", ">", 1000000);
Swift
citiesRef .whereField("state", isGreaterThanOrEqualTo: "CA") .whereField("state", isLessThanOrEqualTo: "IN") citiesRef .whereField("state", isEqualTo: "CA") .whereField("population", isGreaterThan: 1000000)
Objective‑C
[[citiesRef queryWhereField:@"state" isGreaterThanOrEqualTo:@"CA"] queryWhereField:@"state" isLessThanOrEqualTo:@"IN"]; [[citiesRef queryWhereField:@"state" isEqualTo:@"CA"] queryWhereField:@"population" isGreaterThan:@1000000];
Kotlin+KTX
citiesRef.whereGreaterThanOrEqualTo("state", "CA") .whereLessThanOrEqualTo("state", "IN") citiesRef.whereEqualTo("state", "CA") .whereGreaterThan("population", 1000000)
Java
citiesRef.whereGreaterThanOrEqualTo("state", "CA") .whereLessThanOrEqualTo("state", "IN"); citiesRef.whereEqualTo("state", "CA") .whereGreaterThan("population", 1000000);
Dart
final citiesRef = db.collection("cities"); citiesRef .where("state", isGreaterThanOrEqualTo: "CA") .where("state", isLessThanOrEqualTo: "IN"); citiesRef .where("state", isEqualTo: "CA") .where("population", isGreaterThan: 1000000);
Java
Python
Python
C++
cities_ref.WhereGreaterThanOrEqualTo("state", FieldValue::String("CA")) .WhereLessThanOrEqualTo("state", FieldValue::String("IN")); cities_ref.WhereEqualTo("state", FieldValue::String("CA")) .WhereGreaterThan("population", FieldValue::Integer(1000000));
Node.js
Go
PHP
Unity
Query rangeQuery = citiesRef .WhereGreaterThanOrEqualTo("State", "CA") .WhereLessThanOrEqualTo("State", "IN");
C#
Ruby
No válido: Filtros de rango en diferentes campos
Web version 9
import { query, where } from "firebase/firestore"; const q = query(citiesRef, where("state", ">=", "CA"), where("population", ">", 100000));
Web version 8
citiesRef.where("state", ">=", "CA").where("population", ">", 100000);
Swift
citiesRef .whereField("state", isGreaterThanOrEqualTo: "CA") .whereField("population", isGreaterThan: 1000000)
Objective‑C
[[citiesRef queryWhereField:@"state" isGreaterThanOrEqualTo:@"CA"] queryWhereField:@"population" isGreaterThan:@1000000];
Kotlin+KTX
citiesRef.whereGreaterThanOrEqualTo("state", "CA") .whereGreaterThan("population", 100000)
Java
citiesRef.whereGreaterThanOrEqualTo("state", "CA").whereGreaterThan("population", 100000);
Dart
final citiesRef = db.collection("cities"); citiesRef .where("state", isGreaterThanOrEqualTo: "CA") .where("population", isGreaterThan: 1000000);
Java
Python
Python
C++
// BAD EXAMPLE -- will crash the program: cities_ref.WhereGreaterThanOrEqualTo("state", FieldValue::String("CA")) .WhereGreaterThan("population", FieldValue::Integer(100000));
Node.js
Go
PHP
Unity
Query invalidRangeQuery = citiesRef .WhereGreaterThanOrEqualTo("State", "CA") .WhereGreaterThan("Population", 1000000);
C#
Ruby
Consultas de grupos de colecciones
Un grupo de colecciones consta de todas las colecciones con el mismo ID. Según la configuración predeterminada, las consultas recuperan los resultados de una sola colección de tu base de datos. Usa una consulta de grupos de colecciones para obtener documentos de un grupo de colecciones y no de una sola colección.
Por ejemplo, para crear un grupo de colecciones de landmarks
, puedes agregar una subcolección de puntos de referencia
a cada ciudad:
Web version 9
import { collection, addDoc } from "firebase/firestore"; const citiesRef = collection(db, 'cities'); await Promise.all([ addDoc(collection(citiesRef, 'SF', 'landmarks'), { name: 'Golden Gate Bridge', type: 'bridge' }), addDoc(collection(citiesRef, 'SF', 'landmarks'), { name: 'Legion of Honor', type: 'museum' }), addDoc(collection(citiesRef, 'LA', 'landmarks'), { name: 'Griffith Park', type: 'park' }), addDoc(collection(citiesRef, 'LA', 'landmarks'), { name: 'The Getty', type: 'museum' }), addDoc(collection(citiesRef, 'DC', 'landmarks'), { name: 'Lincoln Memorial', type: 'memorial' }), addDoc(collection(citiesRef, 'DC', 'landmarks'), { name: 'National Air and Space Museum', type: 'museum' }), addDoc(collection(citiesRef, 'TOK', 'landmarks'), { name: 'Ueno Park', type: 'park' }), addDoc(collection(citiesRef, 'TOK', 'landmarks'), { name: 'National Museum of Nature and Science', type: 'museum' }), addDoc(collection(citiesRef, 'BJ', 'landmarks'), { name: 'Jingshan Park', type: 'park' }), addDoc(collection(citiesRef, 'BJ', 'landmarks'), { name: 'Beijing Ancient Observatory', type: 'museum' }) ]);
Web version 8
var citiesRef = db.collection('cities'); var landmarks = Promise.all([ citiesRef.doc('SF').collection('landmarks').doc().set({ name: 'Golden Gate Bridge', type: 'bridge' }), citiesRef.doc('SF').collection('landmarks').doc().set({ name: 'Legion of Honor', type: 'museum' }), citiesRef.doc('LA').collection('landmarks').doc().set({ name: 'Griffith Park', type: 'park' }), citiesRef.doc('LA').collection('landmarks').doc().set({ name: 'The Getty', type: 'museum' }), citiesRef.doc('DC').collection('landmarks').doc().set({ name: 'Lincoln Memorial', type: 'memorial' }), citiesRef.doc('DC').collection('landmarks').doc().set({ name: 'National Air and Space Museum', type: 'museum' }), citiesRef.doc('TOK').collection('landmarks').doc().set({ name: 'Ueno Park', type: 'park' }), citiesRef.doc('TOK').collection('landmarks').doc().set({ name: 'National Museum of Nature and Science', type: 'museum' }), citiesRef.doc('BJ').collection('landmarks').doc().set({ name: 'Jingshan Park', type: 'park' }), citiesRef.doc('BJ').collection('landmarks').doc().set({ name: 'Beijing Ancient Observatory', type: 'museum' }) ]);
Swift
let citiesRef = db.collection("cities") var data = ["name": "Golden Gate Bridge", "type": "bridge"] citiesRef.document("SF").collection("landmarks").addDocument(data: data) data = ["name": "Legion of Honor", "type": "museum"] citiesRef.document("SF").collection("landmarks").addDocument(data: data) data = ["name": "Griffith Park", "type": "park"] citiesRef.document("LA").collection("landmarks").addDocument(data: data) data = ["name": "The Getty", "type": "museum"] citiesRef.document("LA").collection("landmarks").addDocument(data: data) data = ["name": "Lincoln Memorial", "type": "memorial"] citiesRef.document("DC").collection("landmarks").addDocument(data: data) data = ["name": "National Air and Space Museum", "type": "museum"] citiesRef.document("DC").collection("landmarks").addDocument(data: data) data = ["name": "Ueno Park", "type": "park"] citiesRef.document("TOK").collection("landmarks").addDocument(data: data) data = ["name": "National Museum of Nature and Science", "type": "museum"] citiesRef.document("TOK").collection("landmarks").addDocument(data: data) data = ["name": "Jingshan Park", "type": "park"] citiesRef.document("BJ").collection("landmarks").addDocument(data: data) data = ["name": "Beijing Ancient Observatory", "type": "museum"] citiesRef.document("BJ").collection("landmarks").addDocument(data: data)
Objective‑C
FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"]; NSDictionary *data = @{@"name": @"Golden Gate Bridge", @"type": @"bridge"}; [[[citiesRef documentWithPath:@"SF"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"Legion of Honor", @"type": @"museum"}; [[[citiesRef documentWithPath:@"SF"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"Griffith Park", @"type": @"park"}; [[[citiesRef documentWithPath:@"LA"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"The Getty", @"type": @"museum"}; [[[citiesRef documentWithPath:@"LA"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"Lincoln Memorial", @"type": @"memorial"}; [[[citiesRef documentWithPath:@"DC"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"National Air and Space Museum", @"type": @"museum"}; [[[citiesRef documentWithPath:@"DC"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"Ueno Park", @"type": @"park"}; [[[citiesRef documentWithPath:@"TOK"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"National Museum of Nature and Science", @"type": @"museum"}; [[[citiesRef documentWithPath:@"TOK"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"Jingshan Park", @"type": @"park"}; [[[citiesRef documentWithPath:@"BJ"] collectionWithPath:@"landmarks"] addDocumentWithData:data]; data = @{@"name": @"Beijing Ancient Observatory", @"type": @"museum"}; [[[citiesRef documentWithPath:@"BJ"] collectionWithPath:@"landmarks"] addDocumentWithData:data];
Kotlin+KTX
val citiesRef = db.collection("cities") val ggbData = mapOf( "name" to "Golden Gate Bridge", "type" to "bridge" ) citiesRef.document("SF").collection("landmarks").add(ggbData) val lohData = mapOf( "name" to "Legion of Honor", "type" to "museum" ) citiesRef.document("SF").collection("landmarks").add(lohData) val gpData = mapOf( "name" to "Griffth Park", "type" to "park" ) citiesRef.document("LA").collection("landmarks").add(gpData) val tgData = mapOf( "name" to "The Getty", "type" to "museum" ) citiesRef.document("LA").collection("landmarks").add(tgData) val lmData = mapOf( "name" to "Lincoln Memorial", "type" to "memorial" ) citiesRef.document("DC").collection("landmarks").add(lmData) val nasaData = mapOf( "name" to "National Air and Space Museum", "type" to "museum" ) citiesRef.document("DC").collection("landmarks").add(nasaData) val upData = mapOf( "name" to "Ueno Park", "type" to "park" ) citiesRef.document("TOK").collection("landmarks").add(upData) val nmData = mapOf( "name" to "National Musuem of Nature and Science", "type" to "museum" ) citiesRef.document("TOK").collection("landmarks").add(nmData) val jpData = mapOf( "name" to "Jingshan Park", "type" to "park" ) citiesRef.document("BJ").collection("landmarks").add(jpData) val baoData = mapOf( "name" to "Beijing Ancient Observatory", "type" to "musuem" ) citiesRef.document("BJ").collection("landmarks").add(baoData)
Java
CollectionReference citiesRef = db.collection("cities"); Map<String, Object> ggbData = new HashMap<>(); ggbData.put("name", "Golden Gate Bridge"); ggbData.put("type", "bridge"); citiesRef.document("SF").collection("landmarks").add(ggbData); Map<String, Object> lohData = new HashMap<>(); lohData.put("name", "Legion of Honor"); lohData.put("type", "museum"); citiesRef.document("SF").collection("landmarks").add(lohData); Map<String, Object> gpData = new HashMap<>(); gpData.put("name", "Griffith Park"); gpData.put("type", "park"); citiesRef.document("LA").collection("landmarks").add(gpData); Map<String, Object> tgData = new HashMap<>(); tgData.put("name", "The Getty"); tgData.put("type", "museum"); citiesRef.document("LA").collection("landmarks").add(tgData); Map<String, Object> lmData = new HashMap<>(); lmData.put("name", "Lincoln Memorial"); lmData.put("type", "memorial"); citiesRef.document("DC").collection("landmarks").add(lmData); Map<String, Object> nasaData = new HashMap<>(); nasaData.put("name", "National Air and Space Museum"); nasaData.put("type", "museum"); citiesRef.document("DC").collection("landmarks").add(nasaData); Map<String, Object> upData = new HashMap<>(); upData.put("name", "Ueno Park"); upData.put("type", "park"); citiesRef.document("TOK").collection("landmarks").add(upData); Map<String, Object> nmData = new HashMap<>(); nmData.put("name", "National Museum of Nature and Science"); nmData.put("type", "museum"); citiesRef.document("TOK").collection("landmarks").add(nmData); Map<String, Object> jpData = new HashMap<>(); jpData.put("name", "Jingshan Park"); jpData.put("type", "park"); citiesRef.document("BJ").collection("landmarks").add(jpData); Map<String, Object> baoData = new HashMap<>(); baoData.put("name", "Beijing Ancient Observatory"); baoData.put("type", "museum"); citiesRef.document("BJ").collection("landmarks").add(baoData);
Dart
final citiesRef = db.collection("cities"); final ggbData = {"name": "Golden Gate Bridge", "type": "bridge"}; citiesRef.doc("SF").collection("landmarks").add(ggbData); final lohData = {"name": "Legion of Honor", "type": "museum"}; citiesRef.doc("SF").collection("landmarks").add(lohData); final gpData = {"name": "Griffth Park", "type": "park"}; citiesRef.doc("LA").collection("landmarks").add(gpData); final tgData = {"name": "The Getty", "type": "museum"}; citiesRef.doc("LA").collection("landmarks").add(tgData); final lmData = {"name": "Lincoln Memorial", "type": "memorial"}; citiesRef.doc("DC").collection("landmarks").add(lmData); final nasaData = { "name": "National Air and Space Museum", "type": "museum" }; citiesRef.doc("DC").collection("landmarks").add(nasaData); final upData = {"name": "Ueno Park", "type": "park"}; citiesRef.doc("TOK").collection("landmarks").add(upData); final nmData = { "name": "National Musuem of Nature and Science", "type": "museum" }; citiesRef.doc("TOK").collection("landmarks").add(nmData); final jpData = {"name": "Jingshan Park", "type": "park"}; citiesRef.doc("BJ").collection("landmarks").add(jpData); final baoData = {"name": "Beijing Ancient Observatory", "type": "musuem"}; citiesRef.doc("BJ").collection("landmarks").add(baoData);
Java
Python
Python
C++
// This is not yet supported.
Node.js
Go
PHP
Unity
// Not yet supported in the Unity SDK
C#
Ruby
De las consultas descritas anteriormente, podemos usar las simples para consultar la subcolección de landmarks
de una sola ciudad o las compuestas a fin de obtener los resultados de las subcolecciones landmarks
de cada ciudad de una vez.
El grupo de colecciones landmarks
consta de todas las colecciones con el ID landmarks
y se puede examinar con una consulta de grupos de colecciones. Por ejemplo,
con esta consulta de grupos de colecciones se obtienen todos los puntos de referencia museum
en todas las ciudades:
Web version 9
import { collectionGroup, query, where, getDocs } from "firebase/firestore"; const museums = query(collectionGroup(db, 'landmarks'), where('type', '==', 'museum')); const querySnapshot = await getDocs(museums); querySnapshot.forEach((doc) => { console.log(doc.id, ' => ', doc.data()); });
Web version 8
var museums = db.collectionGroup('landmarks').where('type', '==', 'museum'); museums.get().then((querySnapshot) => { querySnapshot.forEach((doc) => { console.log(doc.id, ' => ', doc.data()); }); });
Swift
db.collectionGroup("landmarks").whereField("type", isEqualTo: "museum").getDocuments { (snapshot, error) in // ... }
Objective‑C
[[[self.db collectionGroupWithID:@"landmarks"] queryWhereField:@"type" isEqualTo:@"museum"] getDocumentsWithCompletion:^(FIRQuerySnapshot *snapshot, NSError *error) { // ... }];
Kotlin+KTX
db.collectionGroup("landmarks").whereEqualTo("type", "museum").get() .addOnSuccessListener { queryDocumentSnapshots -> // ... }
Java
db.collectionGroup("landmarks").whereEqualTo("type", "museum").get() .addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() { @Override public void onSuccess(QuerySnapshot queryDocumentSnapshots) { // ... } });
Dart
db .collectionGroup("landmarks") .where("type", isEqualTo: "museum") .get() .then( (res) => print("Successfully completed"), onError: (e) => print("Error completing: $e"), );
Java
Python
Python
C++
// This is not yet supported.
Node.js
Go
PHP
Unity
// Not yet supported in the Unity SDK
C#
Ruby
Antes de usar una consulta de grupos de colecciones, debes crear un índice que la admita. Puedes crear un índice mediante un mensaje de error, la consola o Firebase CLI.
En el caso de los SDK para dispositivos móviles y la Web, también debes crear reglas que te permitan realizar consultas de grupos de colecciones.
Limitaciones de las consultas
En la siguiente lista, se resumen las limitaciones de las consultas de Cloud Firestore:
- Cloud Firestore proporciona compatibilidad limitada con las consultas
OR
lógicas. Los operadoresin
yarray-contains-any
son compatibles con unOR
lógico de hasta 10 condiciones de igualdad (==
) oarray-contains
en un solo campo. En otros casos, crea una consulta independiente para cada condición deOR
y combina los resultados en tu app. - En una consulta compuesta, las comparaciones de intervalo (
<
,<=
,>
y>=
) y desigualdad (!=
ynot-in
) deben aplicar filtros en el mismo campo. - Puedes usar como máximo una cláusula
array-contains
por consulta. No puedes combinararray-contains
conarray-contains-any
. - Puedes usar como máximo una cláusula
in
,not-in
oarray-contains-any
por consulta. No puedes combinarin
,not-in
yarray-contains-any
en la misma consulta. - No puedes ordenar tu consulta por un campo incluido en una cláusula de igualdad (
==
) oin
. - La suma de filtros, órdenes y la ruta del documento principal (1 para una subcolección o 0 para una colección raíz) en una consulta no puede ser mayor que 100.
Próximos pasos
- Obtén información para ordenar y limitar los datos en los resultados de la consulta.
- Guarda las lecturas cuando solo quieras contar los resultados.