क्वेरी कर्सर की मदद से डेटा पर नंबर डालें

Cloud Firestore में क्वेरी कर्सर की मदद से, क्वेरी से मिले डेटा को बैच में बांटा जा सकता है. इसके लिए, क्वेरी में तय किए गए पैरामीटर का इस्तेमाल किया जाता है.

क्वेरी कर्सर, किसी क्वेरी के शुरुआती और आखिरी पॉइंट तय करते हैं. इसकी मदद से, ये काम किए जा सकते हैं:

  • डेटा का सबसेट दिखाता है.
  • क्वेरी के नतीजों पर नंबर डालें.

हालांकि, किसी क्वेरी के लिए कोई खास रेंज तय करने के लिए, आपको सामान्य क्वेरी में बताए गए where() तरीकों का इस्तेमाल करना चाहिए.

क्वेरी में सामान्य कर्सर जोड़ना

किसी क्वेरी का शुरुआती पॉइंट तय करने के लिए, startAt() या startAfter() तरीकों का इस्तेमाल करें. startAt() तरीके में, शुरुआती पॉइंट शामिल होता है, जबकि startAfter() तरीके में शामिल नहीं है.

उदाहरण के लिए, अगर किसी क्वेरी में startAt(A) का इस्तेमाल किया जाता है, तो यह पूरे अक्षर दिखाता है. अगर इसके बजाय startAfter(A) का इस्तेमाल किया जाता है, तो यह B-Z दिखाता है.

Web

import { query, orderBy, startAt } from "firebase/firestore";  

const q = query(citiesRef, orderBy("population"), startAt(1000000));

Web

citiesRef.orderBy("population").startAt(1000000);
Swift
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Get all cities with population over one million, ordered by population.
db.collection("cities")
  .order(by: "population")
  .start(at: [1000000])
Objective-C
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Get all cities with population over one million, ordered by population.
[[[db collectionWithPath:@"cities"]
    queryOrderedByField:@"population"]
    queryStartingAtValues:@[ @1000000 ]];

Kotlin+KTX

// Get all cities with a population >= 1,000,000, ordered by population,
db.collection("cities")
    .orderBy("population")
    .startAt(1000000)

Java

// Get all cities with a population >= 1,000,000, ordered by population,
db.collection("cities")
        .orderBy("population")
        .startAt(1000000);

Dart

db.collection("cities").orderBy("population").startAt([1000000]);
Java
Query query = cities.orderBy("population").startAt(4921000L);
Python
cities_ref = db.collection("cities")
query_start_at = cities_ref.order_by("population").start_at({"population": 1000000})

Python

cities_ref = db.collection("cities")
query_start_at = cities_ref.order_by("population").start_at({"population": 1000000})
C++
// Get all cities with a population >= 1,000,000, ordered by population,
db->Collection("cities")
    .OrderBy("population")
    .StartAt({FieldValue::Integer(1000000)});
Node.js
const startAtRes = await db.collection('cities')
  .orderBy('population')
  .startAt(1000000)
  .get();
शुरू करें
query := client.Collection("cities").OrderBy("population", firestore.Asc).StartAt(1000000)
PHP

PHP

Cloud Firestore क्लाइंट बनाने और इंस्टॉल करने के बारे में ज़्यादा जानकारी के लिए, यह लेख पढ़ें Cloud Firestore क्लाइंट लाइब्रेरी.

$query = $citiesRef
    ->orderBy('population')
    ->startAt([1000000]);
Unity
Query query = citiesRef.OrderBy("Population").StartAt(1000000);
C#
Query query = citiesRef.OrderBy("Population").StartAt(1000000);
Ruby
query = cities_ref.order("population").start_at(1_000_000)

इसी तरह, एंड पॉइंट तय करने के लिए, endAt() या endBefore() वाले तरीके का इस्तेमाल करें आपके सवाल के नतीजों के लिए.

Web

import { query, orderBy, endAt } from "firebase/firestore";  

const q = query(citiesRef, orderBy("population"), endAt(1000000));

Web

citiesRef.orderBy("population").endAt(1000000);
Swift
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Get all cities with population less than one million, ordered by population.
db.collection("cities")
  .order(by: "population")
  .end(at: [1000000])
Objective-C
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Get all cities with population less than one million, ordered by population.
[[[db collectionWithPath:@"cities"]
    queryOrderedByField:@"population"]
    queryEndingAtValues:@[ @1000000 ]];

Kotlin+KTX

// Get all cities with a population <= 1,000,000, ordered by population,
db.collection("cities")
    .orderBy("population")
    .endAt(1000000)

Java

// Get all cities with a population <= 1,000,000, ordered by population,
db.collection("cities")
        .orderBy("population")
        .endAt(1000000);

Dart

db.collection("cities").orderBy("population").endAt([1000000]);
Java
Query query = cities.orderBy("population").endAt(4921000L);
Python
cities_ref = db.collection("cities")
query_end_at = cities_ref.order_by("population").end_at({"population": 1000000})

Python

cities_ref = db.collection("cities")
query_end_at = cities_ref.order_by("population").end_at({"population": 1000000})
C++
// Get all cities with a population <= 1,000,000, ordered by population,
db->Collection("cities")
    .OrderBy("population")
    .EndAt({FieldValue::Integer(1000000)});
Node.js
const endAtRes = await db.collection('cities')
  .orderBy('population')
  .endAt(1000000)
  .get();
शुरू करें
query := client.Collection("cities").OrderBy("population", firestore.Asc).EndAt(1000000)
PHP

PHP

Cloud Firestore क्लाइंट बनाने और इंस्टॉल करने के बारे में ज़्यादा जानकारी के लिए, यह लेख पढ़ें Cloud Firestore क्लाइंट लाइब्रेरी.

$query = $citiesRef
    ->orderBy('population')
    ->endAt([1000000]);
Unity
Query query = citiesRef.OrderBy("Population").EndAt(1000000);
C#
Query query = citiesRef.OrderBy("Population").EndAt(1000000);
Ruby
query = cities_ref.order("population").end_at(1_000_000)

क्वेरी कर्सर को परिभाषित करने के लिए दस्तावेज़ के स्नैपशॉट का इस्तेमाल करें

कर्सर क्लॉज़ में दस्तावेज़ के स्नैपशॉट को शुरुआती या आखिरी चरण के तौर पर भी पास किया जा सकता है क्वेरी कर्सर का बिंदु. दस्तावेज़ के स्नैपशॉट में मौजूद वैल्यू, वैल्यू डालें.

उदाहरण के लिए, "सैन फ़्रांसिस्को" का स्नैपशॉट लें आपके डेटा में मौजूद दस्तावेज़ शहरों और जनसंख्याओं का एक समूह है. इसके बाद, उस दस्तावेज़ के स्नैपशॉट का इस्तेमाल, जनसंख्या से जुड़ी क्वेरी के कर्सर के शुरुआती पॉइंट के तौर पर करें. आपकी क्वेरी में सभी शहर दिखेंगे की जनसंख्या, सैन फ़्रांसिस्को की जनसंख्या से ज़्यादा या उसके बराबर हो, जैसा कि दस्तावेज़ का स्नैपशॉट.

Web

import { collection, doc, getDoc, query, orderBy, startAt } from "firebase/firestore";  
const citiesRef = collection(db, "cities");

const docSnap = await getDoc(doc(citiesRef, "SF"));

// Get all cities with a population bigger than San Francisco
const biggerThanSf = query(citiesRef, orderBy("population"), startAt(docSnap));
// ...

Web

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

return citiesRef.doc("SF").get().then((doc) => {
    // Get all cities with a population bigger than San Francisco
    var biggerThanSf = citiesRef
        .orderBy("population")
        .startAt(doc);

    // ...
});
Swift
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
db.collection("cities")
  .document("SF")
  .addSnapshotListener { (document, error) in
    guard let document = document else {
      print("Error retreving cities: \(error.debugDescription)")
      return
    }

    // Get all cities with a population greater than or equal to San Francisco.
    let sfSizeOrBigger = db.collection("cities")
      .order(by: "population")
      .start(atDocument: document)
  }
Objective-C
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
[[[db collectionWithPath:@"cities"] documentWithPath:@"SF"]
    addSnapshotListener:^(FIRDocumentSnapshot *snapshot, NSError *error) {
      if (snapshot == nil) {
        NSLog(@"Error retreiving cities: %@", error);
        return;
      }
      // Get all cities with a population greater than or equal to San Francisco.
      FIRQuery *sfSizeOrBigger = [[[db collectionWithPath:@"cities"]
          queryOrderedByField:@"population"]
          queryStartingAtDocument:snapshot];
    }];

Kotlin+KTX

// Get the data for "San Francisco"
db.collection("cities").document("SF")
    .get()
    .addOnSuccessListener { documentSnapshot ->
        // Get all cities with a population bigger than San Francisco.
        val biggerThanSf = db.collection("cities")
            .orderBy("population")
            .startAt(documentSnapshot)

        // ...
    }

Java

// Get the data for "San Francisco"
db.collection("cities").document("SF")
        .get()
        .addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
            @Override
            public void onSuccess(DocumentSnapshot documentSnapshot) {
                // Get all cities with a population bigger than San Francisco.
                Query biggerThanSf = db.collection("cities")
                        .orderBy("population")
                        .startAt(documentSnapshot);

                // ...
            }
        });

Dart

db.collection("cities").doc("SF").get().then(
  (documentSnapshot) {
    final biggerThanSf = db
        .collection("cities")
        .orderBy("population")
        .startAtDocument(documentSnapshot);
  },
  onError: (e) => print("Error: $e"),
);
Java
// Fetch the snapshot with an API call, waiting for a maximum of 30 seconds for a result.
ApiFuture<DocumentSnapshot> future = db.collection("cities").document("SF").get();
DocumentSnapshot snapshot = future.get(30, TimeUnit.SECONDS);

// Construct the query
Query query = db.collection("cities").orderBy("population").startAt(snapshot);
Python
doc_ref = db.collection("cities").document("SF")

snapshot = doc_ref.get()
start_at_snapshot = (
    db.collection("cities").order_by("population").start_at(snapshot)
)

Python

doc_ref = db.collection("cities").document("SF")

snapshot = await doc_ref.get()
start_at_snapshot = (
    db.collection("cities").order_by("population").start_at(snapshot)
)
C++
db->Collection("cities").Document("SF").Get().OnCompletion(
    [db](const Future<DocumentSnapshot>& future) {
      if (future.error() == Error::kErrorOk) {
        const DocumentSnapshot& document_snapshot = *future.result();
        Query bigger_than_sf = db->Collection("cities")
                                   .OrderBy("population")
                                   .StartAt({document_snapshot});
        // ...
      }
    });
Node.js
const docRef = db.collection('cities').doc('SF');
const snapshot = await docRef.get();
const startAtSnapshot = db.collection('cities')
  .orderBy('population')
  .startAt(snapshot);

await startAtSnapshot.limit(10).get();
शुरू करें
cities := client.Collection("cities")
dsnap, err := cities.Doc("SF").Get(ctx)
if err != nil {
	fmt.Println(err)
}
query := cities.OrderBy("population", firestore.Asc).StartAt(dsnap.Data()["population"]).Documents(ctx)
PHP

PHP

Cloud Firestore क्लाइंट बनाने और इंस्टॉल करने के बारे में ज़्यादा जानकारी के लिए, यह लेख पढ़ें Cloud Firestore क्लाइंट लाइब्रेरी.

$citiesRef = $db->collection('samples/php/cities');
$docRef = $citiesRef->document('SF');
$snapshot = $docRef->snapshot();

$query = $citiesRef
    ->orderBy('population')
    ->startAt($snapshot);
Unity
CollectionReference citiesRef = db.Collection("cities");
DocumentReference docRef = citiesRef.Document("SF");
docRef.GetSnapshotAsync().ContinueWith((snapshotTask) =>
{
    Query query = citiesRef.OrderBy("Population").StartAt(snapshotTask.Result);
});
C#
CollectionReference citiesRef = db.Collection("cities");
DocumentReference docRef = citiesRef.Document("SF");
DocumentSnapshot snapshot = await docRef.GetSnapshotAsync();
Query query = citiesRef.OrderBy("Population").StartAt(snapshot);
Ruby
doc_ref = firestore.doc "#{collection_path}/SF"
snapshot = doc_ref.get
query = cities_ref.order("population").start_at(snapshot)

क्वेरी को पेज पर दिखाना

limit() तरीके के साथ क्वेरी कर्सर को जोड़कर, क्वेरी को पेज पर दिखाएं. उदाहरण के लिए, बैच के अंतिम दस्तावेज़ को अगला बैच.

Web

import { collection, query, orderBy, startAfter, limit, getDocs } from "firebase/firestore";  

// Query the first page of docs
const first = query(collection(db, "cities"), orderBy("population"), limit(25));
const documentSnapshots = await getDocs(first);

// Get the last visible document
const lastVisible = documentSnapshots.docs[documentSnapshots.docs.length-1];
console.log("last", lastVisible);

// Construct a new query starting at this document,
// get the next 25 cities.
const next = query(collection(db, "cities"),
    orderBy("population"),
    startAfter(lastVisible),
    limit(25));

Web

var first = db.collection("cities")
        .orderBy("population")
        .limit(25);

return first.get().then((documentSnapshots) => {
  // Get the last visible document
  var lastVisible = documentSnapshots.docs[documentSnapshots.docs.length-1];
  console.log("last", lastVisible);

  // Construct a new query starting at this document,
  // get the next 25 cities.
  var next = db.collection("cities")
          .orderBy("population")
          .startAfter(lastVisible)
          .limit(25);
});
Swift
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Construct query for first 25 cities, ordered by population
let first = db.collection("cities")
  .order(by: "population")
  .limit(to: 25)

first.addSnapshotListener { (snapshot, error) in
  guard let snapshot = snapshot else {
    print("Error retreving cities: \(error.debugDescription)")
    return
  }

  guard let lastSnapshot = snapshot.documents.last else {
    // The collection is empty.
    return
  }

  // Construct a new query starting after this document,
  // retrieving the next 25 cities.
  let next = db.collection("cities")
    .order(by: "population")
    .start(afterDocument: lastSnapshot)

  // Use the query for pagination.
  // ...
}
Objective-C
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
FIRQuery *first = [[[db collectionWithPath:@"cities"]
    queryOrderedByField:@"population"]
    queryLimitedTo:25];
[first addSnapshotListener:^(FIRQuerySnapshot *snapshot, NSError *error) {
  if (snapshot == nil) {
    NSLog(@"Error retreiving cities: %@", error);
    return;
  }
  if (snapshot.documents.count == 0) { return; }
  FIRDocumentSnapshot *lastSnapshot = snapshot.documents.lastObject;

  // Construct a new query starting after this document,
  // retreiving the next 25 cities.
  FIRQuery *next = [[[db collectionWithPath:@"cities"]
      queryOrderedByField:@"population"]
      queryStartingAfterDocument:lastSnapshot];
  // Use the query for pagination.
  // ...
}];

Kotlin+KTX

// Construct query for first 25 cities, ordered by population
val first = db.collection("cities")
    .orderBy("population")
    .limit(25)

first.get()
    .addOnSuccessListener { documentSnapshots ->
        // ...

        // Get the last visible document
        val lastVisible = documentSnapshots.documents[documentSnapshots.size() - 1]

        // Construct a new query starting at this document,
        // get the next 25 cities.
        val next = db.collection("cities")
            .orderBy("population")
            .startAfter(lastVisible)
            .limit(25)

        // Use the query for pagination
        // ...
    }

Java

// Construct query for first 25 cities, ordered by population
Query first = db.collection("cities")
        .orderBy("population")
        .limit(25);

first.get()
    .addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
        @Override
        public void onSuccess(QuerySnapshot documentSnapshots) {
            // ...

            // Get the last visible document
            DocumentSnapshot lastVisible = documentSnapshots.getDocuments()
                    .get(documentSnapshots.size() -1);

            // Construct a new query starting at this document,
            // get the next 25 cities.
            Query next = db.collection("cities")
                    .orderBy("population")
                    .startAfter(lastVisible)
                    .limit(25);

            // Use the query for pagination
            // ...
        }
    });

Dart

// Construct query for first 25 cities, ordered by population
final first = db.collection("cities").orderBy("population").limit(25);

first.get().then(
  (documentSnapshots) {
    // Get the last visible document
    final lastVisible = documentSnapshots.docs[documentSnapshots.size - 1];

    // Construct a new query starting at this document,
    // get the next 25 cities.
    final next = db
        .collection("cities")
        .orderBy("population")
        .startAfterDocument(lastVisible).limit(25);

    // Use the query for pagination
    // ...
  },
  onError: (e) => print("Error completing: $e"),
);
Java
// Construct query for first 25 cities, ordered by population.
CollectionReference cities = db.collection("cities");
Query firstPage = cities.orderBy("population").limit(25);

// Wait for the results of the API call, waiting for a maximum of 30 seconds for a result.
ApiFuture<QuerySnapshot> future = firstPage.get();
List<QueryDocumentSnapshot> docs = future.get(30, TimeUnit.SECONDS).getDocuments();

// Construct query for the next 25 cities.
QueryDocumentSnapshot lastDoc = docs.get(docs.size() - 1);
Query secondPage = cities.orderBy("population").startAfter(lastDoc).limit(25);

future = secondPage.get();
docs = future.get(30, TimeUnit.SECONDS).getDocuments();
Python
cities_ref = db.collection("cities")
first_query = cities_ref.order_by("population").limit(3)

# Get the last document from the results
docs = first_query.stream()
last_doc = list(docs)[-1]

# Construct a new query starting at this document
# Note: this will not have the desired effect if
# multiple cities have the exact same population value
last_pop = last_doc.to_dict()["population"]

next_query = (
    cities_ref.order_by("population").start_after({"population": last_pop}).limit(3)
)
# Use the query for pagination
# ...

Python

cities_ref = db.collection("cities")
first_query = cities_ref.order_by("population").limit(3)

# Get the last document from the results
docs = [d async for d in first_query.stream()]
last_doc = list(docs)[-1]

# Construct a new query starting at this document
# Note: this will not have the desired effect if
# multiple cities have the exact same population value
last_pop = last_doc.to_dict()["population"]

next_query = (
    cities_ref.order_by("population").start_after({"population": last_pop}).limit(3)
)
# Use the query for pagination
# ...
C++
// Construct query for first 25 cities, ordered by population
Query first = db->Collection("cities").OrderBy("population").Limit(25);

first.Get().OnCompletion([db](const Future<QuerySnapshot>& future) {
  if (future.error() != Error::kErrorOk) {
    // Handle error...
    return;
  }

  // Get the last visible document
  const QuerySnapshot& document_snapshots = *future.result();
  std::vector<DocumentSnapshot> documents = document_snapshots.documents();
  const DocumentSnapshot& last_visible = documents.back();

  // Construct a new query starting at this document,
  // get the next 25 cities.
  Query next = db->Collection("cities")
                   .OrderBy("population")
                   .StartAfter(last_visible)
                   .Limit(25);

  // Use the query for pagination
  // ...
});
Node.js
const first = db.collection('cities')
  .orderBy('population')
  .limit(3);

const snapshot = await first.get();

// Get the last document
const last = snapshot.docs[snapshot.docs.length - 1];

// Construct a new query starting at this document.
// Note: this will not have the desired effect if multiple
// cities have the exact same population value.
const next = db.collection('cities')
  .orderBy('population')
  .startAfter(last.data().population)
  .limit(3);

// Use the query for pagination
// ...
शुरू करें
cities := client.Collection("cities")

// Get the first 25 cities, ordered by population.
firstPage := cities.OrderBy("population", firestore.Asc).Limit(25).Documents(ctx)
docs, err := firstPage.GetAll()
if err != nil {
	return err
}

// Get the last document.
lastDoc := docs[len(docs)-1]

// Construct a new query to get the next 25 cities.
secondPage := cities.OrderBy("population", firestore.Asc).
	StartAfter(lastDoc.Data()["population"]).
	Limit(25)

// ...
PHP

PHP

Cloud Firestore क्लाइंट बनाने और इंस्टॉल करने के बारे में ज़्यादा जानकारी के लिए, यह लेख पढ़ें Cloud Firestore क्लाइंट लाइब्रेरी.

$citiesRef = $db->collection('samples/php/cities');
$firstQuery = $citiesRef->orderBy('population')->limit(3);

# Get the last document from the results
$documents = $firstQuery->documents();
$lastPopulation = 0;
foreach ($documents as $document) {
    $lastPopulation = $document['population'];
}

# Construct a new query starting at this document
# Note: this will not have the desired effect if multiple cities have the exact same population value
$nextQuery = $citiesRef->orderBy('population')->startAfter([$lastPopulation]);
$snapshot = $nextQuery->documents();
Unity
CollectionReference citiesRef = db.Collection("cities");
Query firstQuery = citiesRef.OrderBy("Population").Limit(3);

// Get the last document from the results
firstQuery.GetSnapshotAsync().ContinueWith((querySnapshotTask) =>
{
    long lastPopulation = 0;
    foreach (DocumentSnapshot documentSnapshot in querySnapshotTask.Result.Documents)
    {
        lastPopulation = documentSnapshot.GetValue<long>("Population");
    }

    // Construct a new query starting at this document.
    // Note: this will not have the desired effect if multiple cities have the exact same population value
    Query secondQuery = citiesRef.OrderBy("Population").StartAfter(lastPopulation);
    Task<QuerySnapshot> secondQuerySnapshot = secondQuery.GetSnapshotAsync();
C#
CollectionReference citiesRef = db.Collection("cities");
Query firstQuery = citiesRef.OrderBy("Population").Limit(3);

// Get the last document from the results
QuerySnapshot querySnapshot = await firstQuery.GetSnapshotAsync();
long lastPopulation = 0;
foreach (DocumentSnapshot documentSnapshot in querySnapshot.Documents)
{
    lastPopulation = documentSnapshot.GetValue<long>("Population");
}

// Construct a new query starting at this document.
// Note: this will not have the desired effect if multiple cities have the exact same population value
Query secondQuery = citiesRef.OrderBy("Population").StartAfter(lastPopulation);
QuerySnapshot secondQuerySnapshot = await secondQuery.GetSnapshotAsync();
Ruby
cities_ref  = firestore.col collection_path
first_query = cities_ref.order("population").limit(3)

# Get the last document from the results.
last_population = 0
first_query.get do |city|
  last_population = city.data[:population]
end

# Construct a new query starting at this document.
# Note: this will not have the desired effect if multiple cities have the exact same population value.
second_query = cities_ref.order("population").start_after(last_population)
second_query.get do |city|
  puts "Document #{city.document_id} returned by paginated query cursor."
end

एक से ज़्यादा फ़ील्ड के आधार पर कर्सर सेट करना

फ़ील्ड वैल्यू (न कि DocumentSnapshot) पर आधारित कर्सर का इस्तेमाल करते समय, अतिरिक्त फ़ील्ड जोड़कर कर्सर की स्थिति को और सटीक बनाएं. यह है खास तौर पर तब उपयोगी होता है, जब आपके डेटा सेट में ऐसे कई दस्तावेज़ हों जिनमें सभी आपके कर्सर फ़ील्ड के लिए समान मान, कर्सर की स्थिति को अस्पष्ट बना देता है. शुरुआत की जानकारी देने के लिए, कर्सर में अतिरिक्त फ़ील्ड वैल्यू जोड़ी जा सकती हैं या एंड पॉइंट इस्तेमाल करें और अस्पष्टता को कम करें.

उदाहरण के लिए, "Springfield" नाम के सभी शहर वाले डेटा सेट में में अमेरिका, तो उस क्वेरी के लिए एक से ज़्यादा शुरुआती पॉइंट होंगे जिसे "स्प्रिंगफ़ील्ड" से शुरू करें:

शहर
नाम राज्य
Springfield मेसाचुसेट्स
Springfield मिसौरी
Springfield विस्कॉन्सिन

किसी खास स्प्रिंगफ़ील्ड से शुरुआत करने के लिए, राज्य को सेकंडरी के तौर पर जोड़ा जा सकता है शर्त लागू होती है.

Web

// Will return all Springfields
import { collection, query, orderBy, startAt } from "firebase/firestore";  
const q1 = query(collection(db, "cities"),
   orderBy("name"),
   orderBy("state"),
   startAt("Springfield"));

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
const q2 = query(collection(db, "cities"),
   orderBy("name"),
   orderBy("state"),
   startAt("Springfield", "Missouri"));

Web

// Will return all Springfields
db.collection("cities")
   .orderBy("name")
   .orderBy("state")
   .startAt("Springfield");

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
db.collection("cities")
   .orderBy("name")
   .orderBy("state")
   .startAt("Springfield", "Missouri");
Swift
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Will return all Springfields
db.collection("cities")
  .order(by: "name")
  .order(by: "state")
  .start(at: ["Springfield"])

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
db.collection("cities")
  .order(by: "name")
  .order(by: "state")
  .start(at: ["Springfield", "Missouri"])
Objective-C
ध्यान दें: यह प्रॉडक्ट WatchOS और App Clip टारगेट पर उपलब्ध नहीं है.
// Will return all Springfields
[[[[db collectionWithPath:@"cities"]
    queryOrderedByField:@"name"]
    queryOrderedByField:@"state"]
    queryStartingAtValues:@[ @"Springfield" ]];
// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
[[[[db collectionWithPath:@"cities"]
   queryOrderedByField:@"name"]
   queryOrderedByField:@"state"]
   queryStartingAtValues:@[ @"Springfield", @"Missouri" ]];

Kotlin+KTX

// Will return all Springfields
db.collection("cities")
    .orderBy("name")
    .orderBy("state")
    .startAt("Springfield")

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
db.collection("cities")
    .orderBy("name")
    .orderBy("state")
    .startAt("Springfield", "Missouri")

Java

// Will return all Springfields
db.collection("cities")
        .orderBy("name")
        .orderBy("state")
        .startAt("Springfield");

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
db.collection("cities")
        .orderBy("name")
        .orderBy("state")
        .startAt("Springfield", "Missouri");

Dart

// Will return all Springfields
db
    .collection("cities")
    .orderBy("name")
    .orderBy("state")
    .startAt(["Springfield"]);

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
db
    .collection("cities")
    .orderBy("name")
    .orderBy("state")
    .startAt(["Springfield", "Missouri"]);
Java
// Will return all Springfields
Query query1 = db.collection("cities").orderBy("name").orderBy("state").startAt("Springfield");

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
Query query2 =
    db.collection("cities").orderBy("name").orderBy("state").startAt("Springfield", "Missouri");
Python
start_at_name = (
    db.collection("cities").order_by("name").start_at({"name": "Springfield"})
)

start_at_name_and_state = (
    db.collection("cities")
    .order_by("name")
    .order_by("state")
    .start_at({"name": "Springfield", "state": "Missouri"})
)

Python

start_at_name = (
    db.collection("cities")
    .order_by("name")
    .order_by("state")
    .start_at({"name": "Springfield"})
)

start_at_name_and_state = (
    db.collection("cities")
    .order_by("name")
    .order_by("state")
    .start_at({"name": "Springfield", "state": "Missouri"})
)
C++
// This is not yet supported.
Node.js
// Will return all Springfields
const startAtNameRes = await db.collection('cities')
  .orderBy('name')
  .orderBy('state')
  .startAt('Springfield')
  .get();

// Will return 'Springfield, Missouri' and 'Springfield, Wisconsin'
const startAtNameAndStateRes = await db.collection('cities')
  .orderBy('name')
  .orderBy('state')
  .startAt('Springfield', 'Missouri')
  .get();
शुरू करें
// Will return all Springfields.
client.Collection("cities").
	OrderBy("name", firestore.Asc).
	OrderBy("state", firestore.Asc).
	StartAt("Springfield")

// Will return Springfields where state comes after Wisconsin.
client.Collection("cities").
	OrderBy("name", firestore.Asc).
	OrderBy("state", firestore.Asc).
	StartAt("Springfield", "Wisconsin")
PHP

PHP

Cloud Firestore क्लाइंट बनाने और इंस्टॉल करने के बारे में ज़्यादा जानकारी के लिए, यह लेख पढ़ें Cloud Firestore क्लाइंट लाइब्रेरी.

// Will return all Springfields
$query1 = $db
    ->collection('samples/php/cities')
    ->orderBy('name')
    ->orderBy('state')
    ->startAt(['Springfield']);

// Will return "Springfield, Missouri" and "Springfield, Wisconsin"
$query2 = $db
    ->collection('samples/php/cities')
    ->orderBy('name')
    ->orderBy('state')
    ->startAt(['Springfield', 'Missouri']);
Unity
Query query1 = db.Collection("cities").OrderBy("Name").OrderBy("State").StartAt("Springfield");
Query query2 = db.Collection("cities").OrderBy("Name").OrderBy("State").StartAt("Springfield", "Missouri");
C#
Query query1 = db.Collection("cities").OrderBy("Name").OrderBy("State").StartAt("Springfield");
Query query2 = db.Collection("cities").OrderBy("Name").OrderBy("State").StartAt("Springfield", "Missouri");
Ruby
# Will return all Springfields
query1 = firestore.col(collection_path).order("name").order("state").start_at("Springfield")

# Will return "Springfield, Missouri" and "Springfield, Wisconsin"
query2 = firestore.col(collection_path).order("name").order("state").start_at(["Springfield", "Missouri"])