Ordinare e limitare delle query Firestore
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Ordinare e limitare delle query Firestore
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Per la documentazione dettagliata che include questo esempio di codice, vedi quanto segue:
Esempio di codice
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[[["Facile da capire","easyToUnderstand","thumb-up"],["Il problema è stato risolto","solvedMyProblem","thumb-up"],["Altra","otherUp","thumb-up"]],[["Difficile da capire","hardToUnderstand","thumb-down"],["Informazioni o codice di esempio errati","incorrectInformationOrSampleCode","thumb-down"],["Mancano le informazioni o gli esempi di cui ho bisogno","missingTheInformationSamplesINeed","thumb-down"],["Problema di traduzione","translationIssue","thumb-down"],["Altra","otherDown","thumb-down"]],[],[[["\u003cp\u003eThis page focuses on ordering and limiting data within Firestore queries, showing various code examples across different languages.\u003c/p\u003e\n"],["\u003cp\u003eThe code samples demonstrate how to use \u003ccode\u003eorderBy\u003c/code\u003e to sort data and \u003ccode\u003elimit\u003c/code\u003e or \u003ccode\u003elimitToLast\u003c/code\u003e to restrict the number of results returned in your Firestore queries.\u003c/p\u003e\n"],["\u003cp\u003eTo use these examples, users need to set up Application Default Credentials for Firestore authentication, with further details available in the provided link.\u003c/p\u003e\n"],["\u003cp\u003eThe examples use various languages like C#, Go, Java, Node.js, PHP, Python, and Ruby to present various methods to order and limit data.\u003c/p\u003e\n"],["\u003cp\u003eMore query sample code can be found on the Google Cloud sample browser.\u003c/p\u003e\n"]]],[],null,["# Ordering and limiting Firestore queries\n\nExplore further\n---------------\n\n\nFor detailed documentation that includes this code sample, see the following:\n\n- [Order and limit data](/firestore/native/docs/query-data/order-limit-data)\n- [Order and limit data with Cloud Firestore](https://firebase.google.com/docs/firestore/query-data/order-limit-data)\n\nCode sample\n-----------\n\n### C#\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n Query query = citiesRef.OrderBy(\"Name\").Limit(3);\n\n### Go\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n query := cities.OrderBy(\"name\", firestore.Asc).Limit(3)\n query := cities.OrderBy(\"name\", firestore.Asc).LimitToLast(3)\n\n### Java\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n Query query = cities.orderBy(\"name\").limit(3);\n Query query = cities.orderBy(\"name\").limitToLast(3);\n\n### Node.js\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n const firstThreeRes = await citiesRef.orderBy('name').limit(3).get();\n\n### PHP\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n $query = $citiesRef-\u003eorderBy('name')-\u003elimit(3);\n\n### Python\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n cities_ref = db.collection(\"cities\")\n query = cities_ref.order_by(\"name\").limit_to_last(2)\n results = query.get()\n\n### Ruby\n\n\nTo authenticate to Firestore, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n query = cities_ref.order(\"name\").limit(3)\n\nWhat's next\n-----------\n\n\nTo search and filter code samples for other Google Cloud products, see the\n[Google Cloud sample browser](/docs/samples?product=firestore)."]]