Cloud Firestore में सरल और मिश्रित क्वेरी निष्पादित करें

क्लाउड फायरस्टोर यह निर्दिष्ट करने के लिए शक्तिशाली क्वेरी कार्यक्षमता प्रदान करता है कि आप संग्रह या संग्रह समूह से कौन से दस्तावेज़ पुनर्प्राप्त करना चाहते हैं। इन प्रश्नों भी किसी के साथ इस्तेमाल किया जा सकता get() या addSnapshotListener() , में वर्णित के रूप डेटा प्राप्त और समयोचित अपडेट प्राप्त करें

उदाहरण डेटा

आरंभ करने के लिए, शहरों के बारे में कुछ डेटा लिखें ताकि हम इसे वापस पढ़ने के विभिन्न तरीकों को देख सकें:

वेब संस्करण 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"] });

वेब संस्करण 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"] });
तीव्र
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"]
    ])
उद्देश्य सी
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"]
}];

जावा

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);

कोटलिन + केटीएक्स

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)
जावा
CollectionReference cities = db.collection("cities");
List<ApiFuture<WriteResult>> futures = new ArrayList<>();
futures.add(
    cities
        .document("SF")
        .set(
            new City(
                "San Francisco",
                "CA",
                "USA",
                false,
                860000L,
                Arrays.asList("west_coast", "norcal"))));
futures.add(
    cities
        .document("LA")
        .set(
            new City(
                "Los Angeles",
                "CA",
                "USA",
                false,
                3900000L,
                Arrays.asList("west_coast", "socal"))));
futures.add(
    cities
        .document("DC")
        .set(
            new City(
                "Washington D.C.", null, "USA", true, 680000L, Arrays.asList("east_coast"))));
futures.add(
    cities
        .document("TOK")
        .set(
            new City(
                "Tokyo", null, "Japan", true, 9000000L, Arrays.asList("kanto", "honshu"))));
futures.add(
    cities
        .document("BJ")
        .set(
            new City(
                "Beijing",
                null,
                "China",
                true,
                21500000L,
                Arrays.asList("jingjinji", "hebei"))));
// (optional) block on documents successfully added
ApiFutures.allAsList(futures).get();
अजगर
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())

अजगर

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()
)
सी++
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
const citiesRef = db.collection('cities');

await citiesRef.doc('SF').set({
  name: 'San Francisco', state: 'CA', country: 'USA',
  capital: false, population: 860000,
  regions: ['west_coast', 'norcal']
});
await citiesRef.doc('LA').set({
  name: 'Los Angeles', state: 'CA', country: 'USA',
  capital: false, population: 3900000,
  regions: ['west_coast', 'socal']
});
await citiesRef.doc('DC').set({
  name: 'Washington, D.C.', state: null, country: 'USA',
  capital: true, population: 680000,
  regions: ['east_coast']
});
await citiesRef.doc('TOK').set({
  name: 'Tokyo', state: null, country: 'Japan',
  capital: true, population: 9000000,
  regions: ['kanto', 'honshu']
});
await citiesRef.doc('BJ').set({
  name: 'Beijing', state: null, country: 'China',
  capital: true, population: 21500000,
  regions: ['jingjinji', 'hebei']
});
जाना
cities := []struct {
	id string
	c  City
}{
	{
		id: "SF",
		c: City{Name: "San Francisco", State: "CA", Country: "USA",
			Capital: false, Population: 860000,
			Regions: []string{"west_coast", "norcal"}},
	},
	{
		id: "LA",
		c: City{Name: "Los Angeles", State: "CA", Country: "USA",
			Capital: false, Population: 3900000,
			Regions: []string{"west_coast", "socal"}},
	},
	{
		id: "DC",
		c: City{Name: "Washington D.C.", Country: "USA",
			Capital: true, Population: 680000,
			Regions: []string{"east_coast"}},
	},
	{
		id: "TOK",
		c: City{Name: "Tokyo", Country: "Japan",
			Capital: true, Population: 9000000,
			Regions: []string{"kanto", "honshu"}},
	},
	{
		id: "BJ",
		c: City{Name: "Beijing", Country: "China",
			Capital: true, Population: 21500000,
			Regions: []string{"jingjinji", "hebei"}},
	},
}
for _, c := range cities {
	if _, err := client.Collection("cities").Doc(c.id).Set(ctx, c.c); err != nil {
		return err
	}
}
पीएचपी
$citiesRef = $db->collection('samples/php/cities');
$citiesRef->document('SF')->set([
    'name' => 'San Francisco',
    'state' => 'CA',
    'country' => 'USA',
    'capital' => false,
    'population' => 860000,
    'regions' => ['west_coast', 'norcal']
]);
$citiesRef->document('LA')->set([
    'name' => 'Los Angeles',
    'state' => 'CA',
    'country' => 'USA',
    'capital' => false,
    'population' => 3900000,
    'regions' => ['west_coast', 'socal']
]);
$citiesRef->document('DC')->set([
    'name' => 'Washington D.C.',
    'state' => null,
    'country' => 'USA',
    'capital' => true,
    'population' => 680000,
    'regions' => ['east_coast']
]);
$citiesRef->document('TOK')->set([
    'name' => 'Tokyo',
    'state' => null,
    'country' => 'Japan',
    'capital' => true,
    'population' => 9000000,
    'regions' => ['kanto', 'honshu']
]);
$citiesRef->document('BJ')->set([
    'name' => 'Beijing',
    'state' => null,
    'country' => 'China',
    'capital' => true,
    'population' => 21500000,
    'regions' => ['jingjinji', 'hebei']
]);
printf('Added example cities data to the cities collection.' . PHP_EOL);
एकता
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"} }
});
सी#
CollectionReference citiesRef = db.Collection("cities");
await 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"} }
});
await 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"} }
});
await 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"} }
});
await citiesRef.Document("TOK").SetAsync(new Dictionary<string, object>(){
    { "Name", "Tokyo" },
    { "State", null },
    { "Country", "Japan" },
    { "Capital", true },
    { "Population", 9000000 },
    { "Regions", new ArrayList{"kanto", "honshu"} }
});
await citiesRef.Document("BJ").SetAsync(new Dictionary<string, object>(){
    { "Name", "Beijing" },
    { "State", null },
    { "Country", "China" },
    { "Capital", true },
    { "Population", 21500000 },
    { "Regions", new ArrayList{"jingjinji", "hebei"} }
});
Console.WriteLine("Added example cities data to the cities collection.");
माणिक
cities_ref = firestore.col collection_path
cities_ref.doc("SF").set(
  {
    name:       "San Francisco",
    state:      "CA",
    country:    "USA",
    capital:    false,
    population: 860_000,
    regions:    ["west_coast", "norcal"]
  }
)
cities_ref.doc("LA").set(
  {
    name:       "Los Angeles",
    state:      "CA",
    country:    "USA",
    capital:    false,
    population: 3_900_000,
    regions:    ["west_coast", "socal"]
  }
)
cities_ref.doc("DC").set(
  {
    name:       "Washington D.C.",
    state:      nil,
    country:    "USA",
    capital:    true,
    population: 680_000,
    regions:    ["east_coast"]
  }
)
cities_ref.doc("TOK").set(
  {
    name:       "Tokyo",
    state:      nil,
    country:    "Japan",
    capital:    true,
    population: 9_000_000,
    regions:    ["kanto", "honshu"]
  }
)
cities_ref.doc("BJ").set(
  {
    name:       "Beijing",
    state:      nil,
    country:    "China",
    capital:    true,
    population: 21_500_000,
    regions:    ["jingjinji", "hebei"]
  }
)

सरल प्रश्न

निम्न क्वेरी देता है राज्य के साथ सभी शहरों CA :

वेब संस्करण 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"));

वेब संस्करण 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");
तीव्र
// 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")
उद्देश्य सी
// 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"];

जावा

// Create a reference to the cities collection
CollectionReference citiesRef = db.collection("cities");

// Create a query against the collection.
Query query = citiesRef.whereEqualTo("state", "CA");

कोटलिन + केटीएक्स

// Create a reference to the cities collection
val citiesRef = db.collection("cities")

// Create a query against the collection.
val query = citiesRef.whereEqualTo("state", "CA")
जावा
// Create a reference to the cities collection
CollectionReference cities = db.collection("cities");
// Create a query against the collection.
Query query = cities.whereEqualTo("state", "CA");
// retrieve  query results asynchronously using query.get()
ApiFuture<QuerySnapshot> querySnapshot = query.get();

for (DocumentSnapshot document : querySnapshot.get().getDocuments()) {
  System.out.println(document.getId());
}
अजगर
# Create a reference to the cities collection
cities_ref = db.collection(u'cities')

# Create a query against the collection
query_ref = cities_ref.where(u'state', u'==', u'CA')

अजगर

# Create a reference to the cities collection
cities_ref = db.collection("cities")

# Create a query against the collection
query_ref = cities_ref.where("state", "==", "CA")
सी++
CollectionReference cities_ref = db->Collection("cities");
// Create a query against the collection.
Query query_ca =
    cities_ref.WhereEqualTo("state", FieldValue::String("CA"));
Node.js
// Create a reference to the cities collection
const citiesRef = db.collection('cities');

// Create a query against the collection
const queryRef = citiesRef.where('state', '==', 'CA');
जाना
query := client.Collection("cities").Where("state", "==", "CA")
पीएचपी
$citiesRef = $db->collection('samples/php/cities');
$query = $citiesRef->where('state', '=', 'CA');
$snapshot = $query->documents();
foreach ($snapshot as $document) {
    printf('Document %s returned by query state=CA' . PHP_EOL, $document->id());
}
एकता
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));
    } 
});
सी#
CollectionReference citiesRef = db.Collection("cities");
Query query = citiesRef.WhereEqualTo("State", "CA");
QuerySnapshot querySnapshot = await query.GetSnapshotAsync();
foreach (DocumentSnapshot documentSnapshot in querySnapshot.Documents)
{
    Console.WriteLine("Document {0} returned by query State=CA", documentSnapshot.Id);
}
माणिक
cities_ref = firestore.col collection_path

query = cities_ref.where "state", "=", "CA"

query.get do |city|
  puts "Document #{city.document_id} returned by query state=CA."
end

निम्नलिखित क्वेरी सभी राजधानी शहरों को लौटाती है:

वेब संस्करण 9

import { collection, query, where } from "firebase/firestore";
const citiesRef = collection(db, "cities");

const q = query(citiesRef, where("capital", "==", true));

वेब संस्करण 8

var citiesRef = db.collection("cities");

var query = citiesRef.where("capital", "==", true);
तीव्र
let capitalCities = db.collection("cities").whereField("capital", isEqualTo: true)
उद्देश्य सी
FIRQuery *capitalCities =
    [[self.db collectionWithPath:@"cities"] queryWhereField:@"capital" isEqualTo:@YES];

जावा

Query capitalCities = db.collection("cities").whereEqualTo("capital", true);

कोटलिन + केटीएक्स

val capitalCities = db.collection("cities").whereEqualTo("capital", true)
जावा
// Create a reference to the cities collection
CollectionReference cities = db.collection("cities");
// Create a query against the collection.
Query query = cities.whereEqualTo("capital", true);
// retrieve  query results asynchronously using query.get()
ApiFuture<QuerySnapshot> querySnapshot = query.get();

for (DocumentSnapshot document : querySnapshot.get().getDocuments()) {
  System.out.println(document.getId());
}
अजगर
cities_ref = db.collection(u'cities')

query = cities_ref.where(u'capital', u'==', True)

अजगर

cities_ref = db.collection("cities")

query = cities_ref.where("capital", "==", True)
सी++
Query capital_cities = db->Collection("cities").WhereEqualTo(
    "capital", FieldValue::Boolean(true));
Node.js
// Create a reference to the cities collection
const citiesRef = db.collection('cities');

// Create a query against the collection
const allCapitalsRes = await citiesRef.where('capital', '==', true).get();
जाना
query := client.Collection("cities").Where("capital", "==", true)
पीएचपी
$citiesRef = $db->collection('samples/php/cities');
$query = $citiesRef->where('capital', '=', true);
$snapshot = $query->documents();
foreach ($snapshot as $document) {
    printf('Document %s returned by query capital=true' . PHP_EOL, $document->id());
}
एकता
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));
    } 
});
सी#
CollectionReference citiesRef = db.Collection("cities");
Query query = citiesRef.WhereEqualTo("Capital", true);
QuerySnapshot querySnapshot = await query.GetSnapshotAsync();
foreach (DocumentSnapshot documentSnapshot in querySnapshot.Documents)
{
    Console.WriteLine("Document {0} returned by query Capital=true", documentSnapshot.Id);
}
माणिक
cities_ref = firestore.col collection_path

query = cities_ref.where "capital", "=", true

query.get do |city|
  puts "Document #{city.document_id} returned by query capital=true."
end

एक क्वेरी निष्पादित करें

एक प्रश्न वस्तु बनाने के बाद, का उपयोग get() परिणाम लाने के लिए समारोह:

वेब संस्करण 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());
});

वेब संस्करण 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);
    });
तीव्र
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())")
            }
        }
}
उद्देश्य सी
[[[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);
        }
      }
    }];

जावा

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());
                }
            }
        });

कोटलिन + केटीएक्स

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)
        }
जावा
//asynchronously retrieve multiple documents
ApiFuture<QuerySnapshot> future =
    db.collection("cities").whereEqualTo("capital", true).get();
// future.get() blocks on response
List<QueryDocumentSnapshot> documents = future.get().getDocuments();
for (DocumentSnapshot document : documents) {
  System.out.println(document.getId() + " => " + document.toObject(City.class));
}
अजगर
# Note: Use of CollectionRef stream() is prefered to get()
docs = db.collection(u'cities').where(u'capital', u'==', True).stream()

for doc in docs:
    print(f'{doc.id} => {doc.to_dict()}')

अजगर

# Note: Use of CollectionRef stream() is prefered to get()
docs = db.collection("cities").where("capital", "==", True).stream()

async for doc in docs:
    print(f"{doc.id} => {doc.to_dict()}")
सी++
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 << '\n';
        }
      } else {
        std::cout << "Error getting documents: " << future.error_message()
                  << '\n';
      }
    });
Node.js
const citiesRef = db.collection('cities');
const snapshot = await citiesRef.where('capital', '==', true).get();
if (snapshot.empty) {
  console.log('No matching documents.');
  return;
}  

snapshot.forEach(doc => {
  console.log(doc.id, '=>', doc.data());
});
जाना
fmt.Println("All capital cities:")
iter := client.Collection("cities").Where("capital", "==", true).Documents(ctx)
for {
	doc, err := iter.Next()
	if err == iterator.Done {
		break
	}
	if err != nil {
		return err
	}
	fmt.Println(doc.Data())
}
पीएचपी
$citiesRef = $db->collection('samples/php/cities');
$query = $citiesRef->where('capital', '=', true);
$documents = $query->documents();
foreach ($documents as $document) {
    if ($document->exists()) {
        printf('Document data for document %s:' . PHP_EOL, $document->id());
        print_r($document->data());
        printf(PHP_EOL);
    } else {
        printf('Document %s does not exist!' . PHP_EOL, $document->id());
    }
}
एकता
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("");
  };
});
सी#
Query capitalQuery = db.Collection("cities").WhereEqualTo("Capital", true);
QuerySnapshot capitalQuerySnapshot = await capitalQuery.GetSnapshotAsync();
foreach (DocumentSnapshot documentSnapshot in capitalQuerySnapshot.Documents)
{
    Console.WriteLine("Document data for {0} document:", documentSnapshot.Id);
    Dictionary<string, object> city = documentSnapshot.ToDictionary();
    foreach (KeyValuePair<string, object> pair in city)
    {
        Console.WriteLine("{0}: {1}", pair.Key, pair.Value);
    }
    Console.WriteLine("");
}
माणिक
cities_ref = firestore.col collection_path

query = cities_ref.where "capital", "=", true

query.get do |city|
  puts "#{city.document_id} data: #{city.data}."
end

देखें डेटा प्राप्त क्वेरी परिणाम पुन: प्राप्त करने के बारे में अधिक जानकारी के लिए। आप यह भी कर सकते हैं एक श्रोता जोड़ने के वर्तमान परिणाम प्राप्त और भविष्य अद्यतन के लिए सुनने के लिए एक सवाल के।

क्वेरी ऑपरेटर

where() एक मैदान पर फिल्टर करने के लिए, एक तुलना ऑपरेटर, और एक मूल्य: विधि तीन पैरामीटर लेता है। क्लाउड फायरस्टोर निम्नलिखित तुलना ऑपरेटरों का समर्थन करता है:

उदाहरण के लिए:

वेब संस्करण 9

const stateQuery = query(citiesRef, where("state", "==", "CA"));
const populationQuery = query(citiesRef, where("population", "<", 100000));
const nameQuery = query(citiesRef, where("name", ">=", "San Francisco"));

वेब संस्करण 8

const stateQuery = citiesRef.where("state", "==", "CA");
const populationQuery = citiesRef.where("population", "<", 100000);
const nameQuery = citiesRef.where("name", ">=", "San Francisco");
तीव्र
let stateQuery = citiesRef.whereField("state", isEqualTo: "CA")
let populationQuery = citiesRef.whereField("population", isLessThan: 100000)
let nameQuery = citiesRef.whereField("name", isGreaterThanOrEqualTo: "San Francisco")
उद्देश्य सी
FIRQuery *stateQuery = [citiesRef queryWhereField:@"state" isEqualTo:@"CA"];
FIRQuery *populationQuery = [citiesRef queryWhereField:@"population" isLessThan:@100000];
FIRQuery *nameQuery = [citiesRef queryWhereField:@"name" isGreaterThanOrEqualTo:@"San Francisco"];

जावा

Query stateQuery = citiesRef.whereEqualTo("state", "CA");
Query populationQuery = citiesRef.whereLessThan("population", 100000);
Query nameQuery = citiesRef.whereGreaterThanOrEqualTo("name", "San Francisco");

कोटलिन + केटीएक्स

val stateQuery = citiesRef.whereEqualTo("state", "CA")
val populationQuery = citiesRef.whereLessThan("population", 100000)
val nameQuery = citiesRef.whereGreaterThanOrEqualTo("name", "San Francisco")
जावा
Query stateQuery = cities.whereEqualTo("state", "CA");
Query populationQuery = cities.whereLessThan("population", 1000000L);
Query nameQuery = cities.whereGreaterThanOrEqualTo("name", "San Francisco");
अजगर
cities_ref = db.collection(u'cities')

cities_ref.where(u'state', u'==', u'CA')
cities_ref.where(u'population', u'<', 1000000)
cities_ref.where(u'name', u'>=', u'San Francisco')

अजगर

cities_ref = db.collection("cities")

cities_ref.where("state", "==", "CA")
cities_ref.where("population", "<", 1000000)
cities_ref.where("name", ">=", "San Francisco")
सी++
cities_ref.WhereEqualTo("state", FieldValue::String("CA"));
cities_ref.WhereLessThan("population", FieldValue::Integer(100000));
cities_ref.WhereGreaterThanOrEqualTo("name",
                                     FieldValue::String("San Francisco"));
Node.js
const stateQueryRes = await citiesRef.where('state', '==', 'CA').get();
const populationQueryRes = await citiesRef.where('population', '<', 1000000).get();
const nameQueryRes = await citiesRef.where('name', '>=', 'San Francisco').get();
जाना
countryQuery := cities.Where("state", "==", "CA")
popQuery := cities.Where("population", "<", 1000000)
cityQuery := cities.Where("name", ">=", "San Francisco")
पीएचपी
$stateQuery = $citiesRef->where('state', '=', 'CA');
$populationQuery = $citiesRef->where('population', '>', 1000000);
$nameQuery = $citiesRef->where('name', '>=', 'San Francisco');
एकता
Query stateQuery = citiesRef.WhereEqualTo("State", "CA");
Query populationQuery = citiesRef.WhereGreaterThan("Population", 1000000);
Query nameQuery = citiesRef.WhereGreaterThanOrEqualTo("Name", "San Francisco");
सी#
Query stateQuery = citiesRef.WhereEqualTo("State", "CA");
Query populationQuery = citiesRef.WhereGreaterThan("Population", 1000000);
Query nameQuery = citiesRef.WhereGreaterThanOrEqualTo("Name", "San Francisco");
माणिक
state_query      = cities_ref.where "state", "=", "CA"
population_query = cities_ref.where "population", ">", 1_000_000
name_query       = cities_ref.where "name", ">=", "San Francisco"

बराबर नहीं ( != )

नहीं बराबर (का प्रयोग करें != ) ऑपरेटर दस्तावेजों जहां भी क्षेत्र मौजूद है और तुलना मूल्य से मेल नहीं खाता वापस जाने के लिए। उदाहरण के लिए:

वेब
citiesRef.where("capital", "!=", false);
तीव्र
let notEqualQuery = citiesRef.whereField("capital", isNotEqualTo: false)
उद्देश्य सी
query = [citiesRef queryWhereField:@"capital" isNotEqualTo:@NO];

जावा

Query notCapitalQuery = citiesRef.whereNotEqualTo("capital", false);

कोटलिन + केटीएक्स

val notCapitalQuery = citiesRef.whereNotEqualTo("capital", false)
जावा
CollectionReference citiesRef = db.collection("cities");

Query query = citiesRef.whereNotEqualTo("capital", false);
अजगर
// Snippet not yet available
सी++
// Snippet not yet available
Node.js
const capitalNotFalseRes = await citiesRef.where('capital', '!=', false).get();
जाना
// Snippet not yet available
पीएचपी
// Snippet not yet available
एकता
// Snippet not yet available
सी#
// Snippet not yet available
माणिक
cities_ref = firestore.col collection_path
query = cities_ref.where "capital", "!=", false

इस क्वेरी हर रिटर्न city दस्तावेज़ जहां capital क्षेत्र के अलावा अन्य एक मूल्य के साथ मौजूद है false या null । इसमें शामिल हैं city दस्तावेजों जहां capital क्षेत्र मूल्य के बराबर होती है true या के अलावा किसी भी गैर बूलियन मान null

इस क्वेरी वापस नहीं करता है city दस्तावेजों जहां capital क्षेत्र मौजूद नहीं है। नहीं-बराबर ( != ) और not-in प्रश्नों दस्तावेजों जहां भी क्षेत्र मौजूद नहीं है शामिल नहीं है।

एक क्षेत्र है, जब यह किसी मान पर सेट है एक खाली स्ट्रिंग (सहित, मौजूद है "" ), null , और NaN (नहीं एक नंबर)। ध्यान दें कि null क्षेत्र मान मेल नहीं खाते != खंड, क्योंकि x != null करने के लिए मूल्यांकन करता undefined

सीमाओं

के लिए नोट निम्नलिखित सीमाओं != प्रश्नों:

  • केवल वही दस्तावेज़ जहां दी गई फ़ील्ड मौजूद है, क्वेरी से मेल खा सकते हैं।
  • आप को जोड़ सकते हैं नहीं not-in और != एक यौगिक क्वेरी में।
  • एक यौगिक क्वेरी में, सीमा ( < , <= , > , >= ) और नहीं के बराबर होती है ( != , not-in ) की तुलना करना होगा एक ही मैदान पर सभी फिल्टर।

सरणी सदस्यता

आप उपयोग कर सकते हैं array-contains सरणी मूल्यों पर आधारित फिल्टर करने के लिए ऑपरेटर। उदाहरण के लिए:

वेब संस्करण 9

import { query, where } from "firebase/firestore";  
const q = query(citiesRef, where("regions", "array-contains", "west_coast"));

वेब संस्करण 8

citiesRef.where("regions", "array-contains", "west_coast");
तीव्र
citiesRef
  .whereField("regions", arrayContains: "west_coast")
उद्देश्य सी
[citiesRef queryWhereField:@"state" arrayContains:@"west_coast"];

जावा

CollectionReference citiesRef = db.collection("cities");

citiesRef.whereArrayContains("regions", "west_coast");

कोटलिन + केटीएक्स

val citiesRef = db.collection("cities")

citiesRef.whereArrayContains("regions", "west_coast")
जावा
CollectionReference citiesRef = db.collection("cities");
Query westCoastQuery = citiesRef.whereArrayContains("regions", "west_coast");
अजगर
cities_ref = db.collection(u'cities')

query = cities_ref.where(u'regions', u'array_contains', u'west_coast')

अजगर

cities_ref = db.collection("cities")

query = cities_ref.where("regions", "array_contains", "west_coast")
सी++
// This is not yet supported.
Node.js
const westCoastCities = citiesRef.where('regions', 'array-contains',
  'west_coast').get();
जाना
query := cities.Where("regions", "array-contains", "west_coast").Documents(ctx)
पीएचपी
$containsQuery = $citiesRef->where('regions', 'array-contains', 'west_coast');
एकता
CollectionReference citiesRef = db.Collection("cities");
Query arrayContainsQuery = citiesRef.WhereArrayContains("region", "west_coast");
सी#
Query query = citiesRef.WhereArrayContains("Regions", "west_coast");
माणिक
cities_ref = firestore.col collection_path
cities = cities_ref.where "regions", "array-contains", "west_coast"

इस क्वेरी हर रिटर्न city दस्तावेज़ जहां regions क्षेत्र एक सरणी है कि होता है west_coast । यदि सरणी में आपके द्वारा क्वेरी किए गए मान के कई उदाहरण हैं, तो दस्तावेज़ को केवल एक बार परिणामों में शामिल किया जाता है।

आप उपयोग कर सकते हैं अधिकतम एक array-contains क्वेरी के अनुसार खंड। आप नहीं जोड़ सकते array-contains साथ array-contains-any

in , not-in , और array-contains-any

का प्रयोग करें in 10 समानता के लिए (गठबंधन करने के लिए ऑपरेटर == एक तार्किक के साथ एक ही मैदान पर) खंड OR । एक in क्वेरी दस्तावेजों जहां भी क्षेत्र तुलना से कोई भी मान से मेल खाता है। उदाहरण के लिए:

वेब
citiesRef.where('country', 'in', ['USA', 'Japan']);
तीव्र
let citiesRef = db.collection("cities")

citiesRef.whereField("country", in: ["USA", "Japan"])
उद्देश्य सी
FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"];

[citiesRef queryWhereField:@"country" in:@[@"USA", @"Japan"]];

जावा

CollectionReference citiesRef = db.collection("cities");

citiesRef.whereIn("country", Arrays.asList("USA", "Japan"));

कोटलिन + केटीएक्स

val citiesRef = db.collection("cities")

citiesRef.whereIn("country", listOf("USA", "Japan"))
जावा
CollectionReference citiesRef = db.collection("cities");

Query query = citiesRef.whereIn("country", Arrays.asList("USA", "Japan"));
अजगर
cities_ref = db.collection(u'cities')

query = cities_ref.where(u'country', u'in', [u'USA', u'Japan'])
return query

अजगर

cities_ref = db.collection("cities")

query = cities_ref.where("country", "in", ["USA", "Japan"])
return query
सी++
// This is not yet supported.
Node.js
const usaOrJapan = await citiesRef.where('country', 'in', ['USA', 'Japan']).get();
जाना
cities := client.Collection("cities")
query := cities.Where("country", "in", []string{"USA", "Japan"}).Documents(ctx)
पीएचपी
// Snippet not yet available
एकता
CollectionReference citiesRef = db.Collection("cities");
List countriesList = new List<object>() {"USA", "Japan"};

Query whereInQuery = citiesRef.WhereIn("country", countriesList);
सी#
Query query = citiesRef.WhereIn("Country", new[] { "USA", "Japan" });
माणिक
cities_ref = firestore.col collection_path
usr_or_japan = cities_ref.where "country", "in", ["USA", "Japan"]

इस क्वेरी हर रिटर्न city दस्तावेज़ जहां country क्षेत्र के लिए निर्धारित है USA या Japan । उदाहरण के आंकड़ों से यह भी शामिल है SF , LA , DC , और TOK दस्तावेजों।

not-in

का प्रयोग करें not-in ऑपरेटर 10 बराबर नहीं (करने के लिए गठबंधन करने के लिए != ) खंड में एक ही मैदान पर एक तार्किक साथ AND । एक not-in क्वेरी दस्तावेजों जहां भी क्षेत्र, मौजूद नहीं है null , और तुलना से कोई भी मान से मेल नहीं खाता। उदाहरण के लिए:

वेब
citiesRef.where('country', 'not-in', ['USA', 'Japan']);
तीव्र
citiesRef.whereField("country", notIn: ["USA", "Japan"])
उद्देश्य सी
[citiesRef queryWhereField:@"country" notIn:@[@"USA", @"Japan"]];

जावा

citiesRef.whereNotIn("country", Arrays.asList("USA", "Japan"));

कोटलिन + केटीएक्स

citiesRef.whereNotIn("country", listOf("USA", "Japan"))
जावा
CollectionReference citiesRef = db.collection("cities");

Query query = citiesRef.whereNotIn("country", Arrays.asList("USA", "Japan"));
अजगर
// Snippet not yet available
सी++
// Snippet not yet available
Node.js
const notUsaOrJapan = await citiesRef.where('country', 'not-in', ['USA', 'Japan']).get();
जाना
// Snippet not yet available
पीएचपी
// Snippet not yet available
एकता
// Snippet not yet available
सी#
// Snippet not yet available
माणिक
cities_ref = firestore.col collection_path
usr_or_japan = cities_ref.where "country", "not_in", ["USA", "Japan"]

इस क्वेरी हर रिटर्न city दस्तावेज़ जहां country क्षेत्र मौजूद है और करने के लिए सेट नहीं है, USA , Japan , या null । उदाहरण के आंकड़ों से यह भी शामिल है London और Hong Kong दस्तावेजों।

not-in प्रश्नों दस्तावेजों जहां भी क्षेत्र मौजूद नहीं है शामिल नहीं है। एक क्षेत्र है, जब यह किसी मान पर सेट है एक खाली स्ट्रिंग (सहित, मौजूद है "" ), null , और NaN (नहीं एक नंबर)। ध्यान दें कि x != null करने के लिए मूल्यांकन करता undefined । एक not-in के साथ क्वेरी null तुलना में से एक मान किसी दस्तावेज़ से नहीं करता है।

array-contains-any

का प्रयोग करें array-contains-any करने के लिए 10 तक गठबंधन करने के लिए ऑपरेटर array-contains एक तार्किक के साथ एक ही मैदान पर खंड OR । एक array-contains-any क्वेरी रिटर्न दस्तावेजों जहां भी क्षेत्र एक सरणी है कि एक या तुलना अधिक मान होता है:

वेब
citiesRef.where('regions', 'array-contains-any',
    ['west_coast', 'east_coast']);
तीव्र
let citiesRef = db.collection("cities")
citiesRef.whereField("regions", arrayContainsAny: ["west_coast", "east_coast"])
उद्देश्य सी
FIRCollectionReference *citiesRef = [self.db collectionWithPath:@"cities"];

[citiesRef queryWhereField:@"regions" arrayContainsAny:@[@"west_coast", @"east_coast"]];

जावा

CollectionReference citiesRef = db.collection("cities");

citiesRef.whereArrayContainsAny("regions", Arrays.asList("west_coast", "east_coast"));

कोटलिन + केटीएक्स

val citiesRef = db.collection("cities")

citiesRef.whereArrayContainsAny("regions", listOf("west_coast", "east_coast"))
जावा
CollectionReference citiesRef = db.collection("cities");

Query query =
    citiesRef.whereArrayContainsAny("regions", Arrays.asList("west_coast", "east_coast"));
अजगर
cities_ref = db.collection(u'cities')

query = cities_ref.where(
    u'regions', u'array_contains_any', [u'west_coast', u'east_coast']
)
return query

अजगर

cities_ref = db.collection("cities")

query = cities_ref.where(
    "regions", "array_contains_any", ["west_coast", "east_coast"]
)
return query
सी++
// This is not yet supported.
Node.js
const coastalCities = await citiesRef.where('regions', 'array-contains-any',
    ['west_coast', 'east_coast']).get();
जाना
cities := client.Collection("cities")
query := cities.Where("regions", "array-contains-any", []string{"west_coast", "east_coast"}).Documents(ctx)
पीएचपी
// Snippet not yet available
एकता
CollectionReference citiesRef = db.Collection("cities");
List regionsList = new List<object>() {"west_coast", "east_coast"};

Query arrayContainsAnyQuery = citiesRef.WhereArrayContainsAny("regions", regionsList);
सी#
Query query = citiesRef.WhereArrayContainsAny("Regions", new[] { "west_coast", "east_coast" });
माणिक
cities_ref = firestore.col collection_path
costal_cities = cities_ref.where "regions", "array-contains-any", ["west_coast", "east_coast"]

इस क्वेरी हर शहर दस्तावेज़ जहां रिटर्न region क्षेत्र एक सरणी है कि होता है west_coast या east_coast । उदाहरण के आंकड़ों से यह भी शामिल है SF , LA , और DC दस्तावेजों।

से परिणाम array-contains-any de-ठगा है। भले ही किसी दस्तावेज़ का सरणी फ़ील्ड एक से अधिक तुलना मानों से मेल खाता हो, परिणाम सेट में वह दस्तावेज़ केवल एक बार शामिल होता है।

array-contains-any हमेशा सरणी डेटा प्रकार से फिल्टर। उदाहरण के लिए, क्वेरी के ऊपर एक शहर दस्तावेज़ जहां एक सरणी के बजाय, वापस नहीं होगा region क्षेत्र स्ट्रिंग है west_coast

आप के लिए एक तुलना मान के रूप एक सरणी मूल्य का उपयोग कर सकते in है, लेकिन विपरीत array-contains-any , सरणी लंबाई, आदेश, और मूल्यों की एक सटीक मिलान के लिए खंड मैचों। उदाहरण के लिए:

वेब
citiesRef.where('region', 'in',
    [['west_coast', 'east_coast']]);
तीव्र
citiesRef.whereField("regions", in: [["west_coast"], ["east_coast"]]);
उद्देश्य सी
[citiesRef queryWhereField:@"regions" in:@[@[@"west_coast"], @[@"east_coast"]]];

जावा

citiesRef.whereIn("regions", Arrays.asList(new String[]{"west_coast"}, new String[]{"east_coast"}));

कोटलिन + केटीएक्स

citiesRef.whereIn("regions", listOf(arrayOf("west_coast"), arrayOf("east_coast")))
जावा
CollectionReference citiesRef = db.collection("cities");

Query query =
    citiesRef.whereIn(
        "regions", Arrays.asList(Arrays.asList("west_coast"), Arrays.asList("east_coast")));
अजगर
cities_ref = db.collection(u'cities')

query = cities_ref.where(
    u'regions', u'in', [[u'west_coast'], [u'east_coast']]
)
return query

अजगर

cities_ref = db.collection("cities")

query = cities_ref.where("regions", "in", [["west_coast"], ["east_coast"]])
return query
सी++
// This is not yet supported.
Node.js
const exactlyOneCoast = await citiesRef.where('region', 'in',
    [['west_coast', 'east_coast']]).get();
जाना
cities := client.Collection("cities")
query := cities.Where("regions", "in", [][]string{{"west_coast"}, {"east_coast"}}).Documents(ctx)
पीएचपी
// Snippet not yet available
एकता
// Not yet supported in the Unity SDK
सी#
Query query = citiesRef.WhereIn("Regions",
    new[] { new[] { "west_coast" }, new[] { "east_coast" } });
माणिक
cities_ref = firestore.col collection_path
exactly_one_cost = cities_ref.where "regions", "in", [["west_coast"], ["east_coast"]]

इस क्वेरी हर शहर दस्तावेज़ रिटर्न जहां region क्षेत्र एक सरणी है कि या तो की ठीक एक तत्व शामिल है west_coast या east_coast । उदाहरण डेटा, केवल से DC इसके साथ दस्तावेज़ पात्र region के क्षेत्र ["east_coast"]SF दस्तावेज़, तथापि, से मेल नहीं खाता, क्योंकि इसके region क्षेत्र है ["west_coast", "norcal"]

सीमाओं

नोट के लिए निम्नलिखित सीमाओं in , not-in , और array-contains-any :

  • in , not-in , और array-contains-any समर्थन 10 तुलना मूल्यों के लिए।
  • आप उपयोग कर सकते हैं अधिकतम एक array-contains क्वेरी के अनुसार खंड। आप नहीं जोड़ सकते array-contains साथ array-contains-any
  • आप सबसे एक में उपयोग कर सकते हैं in , not-in , या array-contains-any क्वेरी के अनुसार खंड। आप इन ऑपरेटरों को एक ही क्वेरी में संयोजित नहीं कर सकते।
  • आप नहीं जोड़ सकते not-in के साथ बराबर होती है नहीं !=
  • आप (एक क्षेत्र एक समानता में शामिल करके अपनी क्वेरी आदेश नहीं दे सकेंगे == ) या in खंड।

यौगिक प्रश्न

आप कर सकते हैं श्रृंखला कई समानता ऑपरेटरों ( == या array-contains ) तरीकों को और अधिक विशिष्ट प्रश्न (तार्किक बनाने के लिए AND )। हालांकि, अगर आप एक बनाना होगा समग्र सूचकांक असमानता ऑपरेटरों के साथ समानता ऑपरेटरों गठबंधन करने के लिए, < , <= , > , और !=

वेब संस्करण 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));

वेब संस्करण 8

const q1 = citiesRef.where("state", "==", "CO").where("name", "==", "Denver");
const q2 = citiesRef.where("state", "==", "CA").where("population", "<", 1000000);
तीव्र
citiesRef
    .whereField("state", isEqualTo: "CO")
    .whereField("name", isEqualTo: "Denver")
citiesRef
    .whereField("state", isEqualTo: "CA")
    .whereField("population", isLessThan: 1000000)
उद्देश्य सी
[[citiesRef queryWhereField:@"state" isEqualTo:@"CO"]
    queryWhereField:@"name" isGreaterThanOrEqualTo:@"Denver"];
[[citiesRef queryWhereField:@"state" isEqualTo:@"CA"]
    queryWhereField:@"population" isLessThan:@1000000];

जावा

citiesRef.whereEqualTo("state", "CO").whereEqualTo("name", "Denver");
citiesRef.whereEqualTo("state", "CA").whereLessThan("population", 1000000);

कोटलिन + केटीएक्स

citiesRef.whereEqualTo("state", "CO").whereEqualTo("name", "Denver")
citiesRef.whereEqualTo("state", "CA").whereLessThan("population", 1000000)
जावा
Query chainedQuery1 = cities.whereEqualTo("state", "CO").whereEqualTo("name", "Denver");
अजगर
cities_ref = db.collection(u'cities')

denver_query = cities_ref.where(
    u'state', u'==', u'CO').where(u'name', u'==', u'Denver')
large_us_cities_query = cities_ref.where(
    u'state', u'==', u'CA').where(u'population', u'>', 1000000)

अजगर

cities_ref = db.collection("cities")

denver_query = cities_ref.where("state", "==", "CO").where("name", "==", "Denver")
large_us_cities_query = cities_ref.where("state", "==", "CA").where(
    "population", ">", 1000000
)
सी++
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
citiesRef.where('state', '==', 'CO').where('name', '==', 'Denver');
citiesRef.where('state', '==', 'CA').where('population', '<', 1000000);
जाना
denverQuery := cities.Where("name", "==", "Denver").Where("state", "==", "CO")
caliQuery := cities.Where("state", "==", "CA").Where("population", "<=", 1000000)
query := cities.Where("country", "==", "USA").Where("population", ">", 5000000)
पीएचपी
$chainedQuery = $citiesRef
    ->where('state', '=', 'CA')
    ->where('name', '=', 'San Francisco');
एकता
Query chainedQuery = citiesRef
    .WhereEqualTo("State", "CA")
    .WhereEqualTo("Name", "San Francisco");
सी#
Query chainedQuery = citiesRef
    .WhereEqualTo("State", "CA")
    .WhereEqualTo("Name", "San Francisco");
माणिक
chained_query = cities_ref.where("state", "=", "CA").where("name", "=", "San Francisco")

आप रेंज प्रदर्शन कर सकते हैं ( < , <= , > , >= ) है या नहीं के बराबर होती है ( != केवल एक ही मैदान पर तुलना), और आप अधिकतम एक बार शामिल कर सकते हैं array-contains या array-contains-any एक यौगिक क्वेरी में खंड :

मान्य: केवल एक ही मैदान पर रेंज फिल्टर

वेब संस्करण 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));

वेब संस्करण 8

const q1 = citiesRef.where("state", ">=", "CA").where("state", "<=", "IN");
const q2 = citiesRef.where("state", "==", "CA").where("population", ">", 1000000);
तीव्र
citiesRef
    .whereField("state", isGreaterThanOrEqualTo: "CA")
    .whereField("state", isLessThanOrEqualTo: "IN")
citiesRef
    .whereField("state", isEqualTo: "CA")
    .whereField("population", isGreaterThan: 1000000)
उद्देश्य सी
[[citiesRef queryWhereField:@"state" isGreaterThanOrEqualTo:@"CA"]
    queryWhereField:@"state" isLessThanOrEqualTo:@"IN"];
[[citiesRef queryWhereField:@"state" isEqualTo:@"CA"]
    queryWhereField:@"population" isGreaterThan:@1000000];

जावा

citiesRef.whereGreaterThanOrEqualTo("state", "CA")
        .whereLessThanOrEqualTo("state", "IN");
citiesRef.whereEqualTo("state", "CA")
        .whereGreaterThan("population", 1000000);

कोटलिन + केटीएक्स

citiesRef.whereGreaterThanOrEqualTo("state", "CA")
        .whereLessThanOrEqualTo("state", "IN")
citiesRef.whereEqualTo("state", "CA")
        .whereGreaterThan("population", 1000000)
जावा
Query validQuery1 =
    cities.whereGreaterThanOrEqualTo("state", "CA").whereLessThanOrEqualTo("state", "IN");
Query validQuery2 = cities.whereEqualTo("state", "CA").whereGreaterThan("population", 1000000);
अजगर
cities_ref = db.collection(u'cities')
cities_ref.where(u'state', u'>=', u'CA').where(u'state', u'<=', u'IN')

अजगर

cities_ref = db.collection("cities")
cities_ref.where("state", ">=", "CA").where("state", "<=", "IN")
सी++
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
citiesRef.where('state', '>=', 'CA').where('state', '<=', 'IN');
citiesRef.where('state', '==', 'CA').where('population', '>', 1000000);
जाना
stateQuery := cities.Where("state", ">=", "CA").Where("state", "<", "IN")
populationQuery := cities.Where("state", "==", "CA").Where("population", ">", 1000000)
पीएचपी
$rangeQuery = $citiesRef
    ->where('state', '>=', 'CA')
    ->where('state', '<=', 'IN');
एकता
Query rangeQuery = citiesRef
    .WhereGreaterThanOrEqualTo("State", "CA")
    .WhereLessThanOrEqualTo("State", "IN");
सी#
Query rangeQuery = citiesRef
    .WhereGreaterThanOrEqualTo("State", "CA")
    .WhereLessThanOrEqualTo("State", "IN");
माणिक
range_query = cities_ref.where("state", ">=", "CA").where("state", "<=", "IN")

अमान्य: रेंज विभिन्न क्षेत्रों पर फिल्टर

वेब संस्करण 9

import { query, where } from "firebase/firestore";  

const q = query(citiesRef, where("state", ">=", "CA"), where("population", ">", 100000));

वेब संस्करण 8

citiesRef.where("state", ">=", "CA").where("population", ">", 100000);
तीव्र
citiesRef
    .whereField("state", isGreaterThanOrEqualTo: "CA")
    .whereField("population", isGreaterThan: 1000000)
उद्देश्य सी
[[citiesRef queryWhereField:@"state" isGreaterThanOrEqualTo:@"CA"]
    queryWhereField:@"population" isGreaterThan:@1000000];

जावा

citiesRef.whereGreaterThanOrEqualTo("state", "CA").whereGreaterThan("population", 100000);

कोटलिन + केटीएक्स

citiesRef.whereGreaterThanOrEqualTo("state", "CA")
        .whereGreaterThan("population", 100000)
जावा
Query invalidRangeQuery =
    cities.whereGreaterThanOrEqualTo("state", "CA").whereGreaterThan("population", 100000);
अजगर
cities_ref = db.collection(u'cities')
cities_ref.where(
    u'state', u'>=', u'CA').where(u'population', u'>=', 1000000)

अजगर

cities_ref = db.collection("cities")
cities_ref.where("state", ">=", "CA").where("population", ">=", 1000000)
सी++
// BAD EXAMPLE -- will crash the program:
cities_ref.WhereGreaterThanOrEqualTo("state", FieldValue::String("CA"))
    .WhereGreaterThan("population", FieldValue::Integer(100000));
Node.js
citiesRef.where('state', '>=', 'CA').where('population', '>', 1000000);
जाना
query := cities.Where("state", ">=", "CA").Where("population", ">", 1000000)
पीएचपी
$invalidRangeQuery = $citiesRef
    ->where('state', '>=', 'CA')
    ->where('population', '>', 1000000);
एकता
Query invalidRangeQuery = citiesRef
    .WhereGreaterThanOrEqualTo("State", "CA")
    .WhereGreaterThan("Population", 1000000);
सी#
Query invalidRangeQuery = citiesRef
    .WhereGreaterThanOrEqualTo("State", "CA")
    .WhereGreaterThan("Population", 1000000);
माणिक
invalid_range_query = cities_ref.where("state", ">=", "CA").where("population", ">", 1_000_000)

संग्रह समूह प्रश्न

एक संग्रह समूह में एक ही आईडी वाले सभी संग्रह होते हैं। डिफ़ॉल्ट रूप से, क्वेरीज़ आपके डेटाबेस में एकल संग्रह से परिणाम प्राप्त करती हैं। एकल संग्रह के बजाय संग्रह समूह से दस्तावेज़ पुनर्प्राप्त करने के लिए संग्रह समूह क्वेरी का उपयोग करें।

उदाहरण के लिए, यदि आप एक बना सकते हैं landmarks प्रत्येक शहर के लिए एक स्थलों subcollection जोड़कर संग्रह समूह:

वेब
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'
    })
]);
तीव्र
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)
उद्देश्य सी
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];

जावा

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);

कोटलिन + केटीएक्स

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)
जावा
CollectionReference cities = db.collection("cities");

final List<ApiFuture<WriteResult>> futures =
    Arrays.asList(
        cities
            .document("SF")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Golden Gate Bridge");
                    put("type", "bridge");
                  }
                }),
        cities
            .document("SF")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Legion of Honor");
                    put("type", "museum");
                  }
                }),
        cities
            .document("LA")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Griffith Park");
                    put("type", "park");
                  }
                }),
        cities
            .document("LA")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "The Getty");
                    put("type", "museum");
                  }
                }),
        cities
            .document("DC")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Lincoln Memorial");
                    put("type", "memorial");
                  }
                }),
        cities
            .document("DC")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "National Air and Space Museum");
                    put("type", "museum");
                  }
                }),
        cities
            .document("TOK")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Ueno Park");
                    put("type", "park");
                  }
                }),
        cities
            .document("TOK")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "National Museum of Nature and Science");
                    put("type", "museum");
                  }
                }),
        cities
            .document("BJ")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Jingshan Park");
                    put("type", "park");
                  }
                }),
        cities
            .document("BJ")
            .collection("landmarks")
            .document()
            .set(
                new HashMap<String, String>() {
                  {
                    put("name", "Beijing Ancient Observatory");
                    put("type", "museum");
                  }
                }));
final List<WriteResult> landmarks = ApiFutures.allAsList(futures).get();
अजगर
cities = db.collection(u'cities')

sf_landmarks = cities.document(u'SF').collection(u'landmarks')
sf_landmarks.document().set({
    u'name': u'Golden Gate Bridge',
    u'type': u'bridge'
})
sf_landmarks.document().set({
    u'name': u'Legion of Honor',
    u'type': u'museum'
})
la_landmarks = cities.document(u'LA').collection(u'landmarks')
la_landmarks.document().set({
    u'name': u'Griffith Park',
    u'type': u'park'
})
la_landmarks.document().set({
    u'name': u'The Getty',
    u'type': u'museum'
})
dc_landmarks = cities.document(u'DC').collection(u'landmarks')
dc_landmarks.document().set({
    u'name': u'Lincoln Memorial',
    u'type': u'memorial'
})
dc_landmarks.document().set({
    u'name': u'National Air and Space Museum',
    u'type': u'museum'
})
tok_landmarks = cities.document(u'TOK').collection(u'landmarks')
tok_landmarks.document().set({
    u'name': u'Ueno Park',
    u'type': u'park'
})
tok_landmarks.document().set({
    u'name': u'National Museum of Nature and Science',
    u'type': u'museum'
})
bj_landmarks = cities.document(u'BJ').collection(u'landmarks')
bj_landmarks.document().set({
    u'name': u'Jingshan Park',
    u'type': u'park'
})
bj_landmarks.document().set({
    u'name': u'Beijing Ancient Observatory',
    u'type': u'museum'
})

अजगर

cities = db.collection("cities")

sf_landmarks = cities.document("SF").collection("landmarks")
await sf_landmarks.document().set({"name": "Golden Gate Bridge", "type": "bridge"})
await sf_landmarks.document().set({"name": "Legion of Honor", "type": "museum"})
la_landmarks = cities.document("LA").collection("landmarks")
await la_landmarks.document().set({"name": "Griffith Park", "type": "park"})
await la_landmarks.document().set({"name": "The Getty", "type": "museum"})
dc_landmarks = cities.document("DC").collection("landmarks")
await dc_landmarks.document().set({"name": "Lincoln Memorial", "type": "memorial"})
await dc_landmarks.document().set(
    {"name": "National Air and Space Museum", "type": "museum"}
)
tok_landmarks = cities.document("TOK").collection("landmarks")
await tok_landmarks.document().set({"name": "Ueno Park", "type": "park"})
await tok_landmarks.document().set(
    {"name": "National Museum of Nature and Science", "type": "museum"}
)
bj_landmarks = cities.document("BJ").collection("landmarks")
await bj_landmarks.document().set({"name": "Jingshan Park", "type": "park"})
await bj_landmarks.document().set(
    {"name": "Beijing Ancient Observatory", "type": "museum"}
)
सी++
// This is not yet supported.
Node.js
const citiesRef = db.collection('cities');

await citiesRef.doc('SF').collection('landmarks').doc().set({
  name: 'Golden Gate Bridge',
  type: 'bridge'
});
await citiesRef.doc('SF').collection('landmarks').doc().set({
  name: 'Legion of Honor',
  type: 'museum'
});
await citiesRef.doc('LA').collection('landmarks').doc().set({
  name: 'Griffith Park',
  type: 'park'
});
await citiesRef.doc('LA').collection('landmarks').doc().set({
  name: 'The Getty',
  type: 'museum'
});
await citiesRef.doc('DC').collection('landmarks').doc().set({
  name: 'Lincoln Memorial',
  type: 'memorial'
});
await citiesRef.doc('DC').collection('landmarks').doc().set({
  name: 'National Air and Space Museum',
  type: 'museum'
});
await citiesRef.doc('TOK').collection('landmarks').doc().set({
  name: 'Ueno Park',
  type: 'park'
});
await citiesRef.doc('TOK').collection('landmarks').doc().set({
  name: 'National Museum of Nature and Science',
  type: 'museum'
});
await citiesRef.doc('BJ').collection('landmarks').doc().set({
  name: 'Jingshan Park',
  type: 'park'
});
await citiesRef.doc('BJ').collection('landmarks').doc().set({ 
  name: 'Beijing Ancient Observatory',
  type: 'museum'
});
जाना
import (
	"context"
	"fmt"

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

// collectionGroupSetup sets up a collection group to query.
func collectionGroupSetup(projectID, cityCollection string) error {
	ctx := context.Background()

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

	landmarks := []struct {
		city, name, t string
	}{
		{"SF", "Golden Gate Bridge", "bridge"},
		{"SF", "Legion of Honor", "museum"},
		{"LA", "Griffith Park", "park"},
		{"LA", "The Getty", "museum"},
		{"DC", "Lincoln Memorial", "memorial"},
		{"DC", "National Air and Space Museum", "museum"},
		{"TOK", "Ueno Park", "park"},
		{"TOK", "National Museum of Nature and Science", "museum"},
		{"BJ", "Jingshan Park", "park"},
		{"BJ", "Beijing Ancient Observatory", "museum"},
	}

	cities := client.Collection(cityCollection)
	for _, l := range landmarks {
		if _, err := cities.Doc(l.city).Collection("landmarks").NewDoc().Set(ctx, map[string]string{
			"name": l.name,
			"type": l.t,
		}); err != nil {
			return fmt.Errorf("Set: %v", err)
		}
	}

	return nil
}
पीएचपी
// Snippet not yet available
एकता
// Not yet supported in the Unity SDK
सी#
await citiesRef.Document("SF").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Golden Gate Bridge", Type = "bridge" });
await citiesRef.Document("SF").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Legion of Honor", Type = "museum" });
await citiesRef.Document("LA").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Griffith Park", Type = "park" });
await citiesRef.Document("DC").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Lincoln Memorial", Type = "memorial" });
await citiesRef.Document("DC").Collection("landmarks").Document()
    .CreateAsync(new { Name = "National Air And Space Museum", Type = "museum" });
await citiesRef.Document("TOK").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Ueno Park", Type = "park" });
await citiesRef.Document("TOK").Collection("landmarks").Document()
    .CreateAsync(new { Name = "National Museum of Nature and Science", Type = "museum" });
await citiesRef.Document("BJ").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Jingshan Park", Type = "park" });
await citiesRef.Document("BJ").Collection("landmarks").Document()
    .CreateAsync(new { Name = "Beijing Ancient Observatory", Type = "museum" });
माणिक
cities_ref = firestore.col collection_path

sf_landmarks = cities_ref.document("SF").collection("landmarks")
sf_landmarks.document.set(
  {
    name: "Golden Gate Bridge",
    type: "bridge"
  }
)
sf_landmarks.document.set(
  {
    name: "Legion of Honor",
    type: "museum"
  }
)

la_landmarks = cities_ref.document("LA").collection("landmarks")
la_landmarks.document.set(
  {
    name: "Griffith Park",
    type: "park"
  }
)
la_landmarks.document.set(
  {
    name: "The Getty",
    type: "museum"
  }
)

dc_landmarks = cities_ref.document("DC").collection("landmarks")
dc_landmarks.document.set(
  {
    name: "Lincoln Memorial",
    type: "memorial"
  }
)
dc_landmarks.document.set(
  {
    name: "National Air and Space Museum",
    type: "museum"
  }
)

tok_landmarks = cities_ref.document("TOK").collection("landmarks")
tok_landmarks.document.set(
  {
    name: "Ueno Park",
    type: "park"
  }
)
tok_landmarks.document.set(
  {
    name: "National Museum of Nature and Science",
    type: "museum"
  }
)

bj_landmarks = cities_ref.document("BJ").collection("landmarks")
bj_landmarks.document.set(
  {
    name: "Jingshan Park",
    type: "park"
  }
)
bj_landmarks.document.set(
  {
    name: "Beijing Ancient Observatory",
    type: "museum"
  }
)

हम सरल और मिश्रित क्वेरी वर्णित एक भी शहर के क्वेरी करने के लिए पहले का उपयोग कर सकते landmarks subcollection, लेकिन आप भी हर शहर के से परिणाम लाने के लिए चाहते हो सकता है landmarks बार में subcollection।

landmarks संग्रह समूह आईडी के साथ सभी संग्रह के होते हैं landmarks , और आप एक संग्रह समूह क्वेरी का उपयोग कर क्वेरी कर सकते हैं। उदाहरण के लिए, इस संग्रह समूह क्वेरी सभी को पुन: प्राप्त museum सभी शहरों में स्थलों:

वेब
->
var museums = db.collectionGroup('landmarks').where('type', '==', 'museum');
museums.get().then((querySnapshot) => {
    querySnapshot.forEach((doc) => {
        console.log(doc.id, ' => ', doc.data());
    });
});
तीव्र
db.collectionGroup("landmarks").whereField("type", isEqualTo: "museum").getDocuments { (snapshot, error) in
    // ...
}
उद्देश्य सी
[[[self.db collectionGroupWithID:@"landmarks"] queryWhereField:@"type" isEqualTo:@"museum"]
    getDocumentsWithCompletion:^(FIRQuerySnapshot *snapshot, NSError *error) {
    // ...
}];

जावा

db.collectionGroup("landmarks").whereEqualTo("type", "museum").get()
        .addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
            @Override
            public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
                // ...
            }
        });

कोटलिन + केटीएक्स

db.collectionGroup("landmarks").whereEqualTo("type", "museum").get()
        .addOnSuccessListener { queryDocumentSnapshots ->
            // ...
        }
जावा
final Query museums = db.collectionGroup("landmarks").whereEqualTo("type", "museum");
final ApiFuture<QuerySnapshot> querySnapshot = museums.get();
for (DocumentSnapshot document : querySnapshot.get().getDocuments()) {
  System.out.println(document.getId());
}
अजगर
museums = db.collection_group(u'landmarks')\
    .where(u'type', u'==', u'museum')
docs = museums.stream()
for doc in docs:
    print(f'{doc.id} => {doc.to_dict()}')

अजगर

museums = db.collection_group("landmarks").where("type", "==", "museum")
docs = museums.stream()
async for doc in docs:
    print(f"{doc.id} => {doc.to_dict()}")
सी++
// This is not yet supported.
Node.js
const querySnapshot = await db.collectionGroup('landmarks').where('type', '==', 'museum').get();
querySnapshot.forEach((doc) => {
  console.log(doc.id, ' => ', doc.data());
});
जाना
import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/firestore"
	"google.golang.org/api/iterator"
)

// collectionGroupQuery runs a collection group query over the data created by
// collectionGroupSetup.
func collectionGroupQuery(w io.Writer, projectID string) error {
	ctx := context.Background()

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

	it := client.CollectionGroup("landmarks").Where("type", "==", "museum").Documents(ctx)
	for {
		doc, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return fmt.Errorf("documents iterator: %v", err)
		}
		fmt.Fprintf(w, "%s: %s", doc.Ref.ID, doc.Data()["name"])
	}

	return nil
}
पीएचपी
// Snippet not yet available
एकता
// Not yet supported in the Unity SDK
सी#
Query museums = db.CollectionGroup("landmarks").WhereEqualTo("Type", "museum");
QuerySnapshot querySnapshot = await museums.GetSnapshotAsync();
foreach (DocumentSnapshot document in querySnapshot.Documents)
{
    Console.WriteLine($"{document.Reference.Path}: {document.GetValue<string>("Name")}");
}
माणिक
museums = firestore.collection_group("landmarks").where("type", "==", "museum")
museums.get do |museum|
  puts "#{museum[:type]} name is #{museum[:name]}."
end

संग्रह समूह क्वेरी का उपयोग करने से पहले, आपको एक इंडेक्स बनाना होगा जो आपके संग्रह समूह क्वेरी का समर्थन करता हो। आपको एक त्रुटि संदेश, कंसोल, या Firebase CLI के माध्यम से एक सूचकांक बना सकते हैं

वेब और मोबाइल SDK के लिए, आप भी चाहिए कि नियमों अपने संग्रह समूह क्वेरी की अनुमति देते बनाने

क्वेरी सीमाएं

निम्न सूची Cloud Firestore क्वेरी सीमाओं को सारांशित करती है:

  • बादल Firestore तार्किक के लिए सीमित समर्थन प्रदान करता है OR प्रश्नों। in , और array-contains-any ऑपरेटरों का समर्थन एक तार्किक OR अधिकतम 10 समानता के ( == ) या array-contains एक भी मैदान पर स्थिति। अन्य मामलों के लिए, प्रत्येक के लिए एक अलग क्वेरी बनाने OR हालत और अपने एप्लिकेशन में क्वेरी परिणाम मर्ज करें।
  • एक यौगिक क्वेरी में, सीमा ( < , <= , > , >= ) और नहीं के बराबर होती है ( != , not-in ) की तुलना करना होगा एक ही मैदान पर सभी फिल्टर।
  • आप उपयोग कर सकते हैं अधिकतम एक array-contains क्वेरी के अनुसार खंड। आप नहीं जोड़ सकते array-contains साथ array-contains-any
  • आप सबसे एक में उपयोग कर सकते हैं in , not-in , या array-contains-any क्वेरी के अनुसार खंड। आप को जोड़ सकते हैं नहीं in , not-in , और array-contains-any एक ही क्वेरी में।
  • आप (एक क्षेत्र एक समानता में शामिल करके अपनी क्वेरी आदेश नहीं दे सकेंगे == ) या in खंड।
  • किसी क्वेरी में फ़िल्टर, सॉर्ट ऑर्डर और पैरेंट दस्तावेज़ पथ (उपसंग्रह के लिए 1, रूट संग्रह के लिए 0) का योग 100 से अधिक नहीं हो सकता।