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[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["難以理解","hardToUnderstand","thumb-down"],["資訊或程式碼範例有誤","incorrectInformationOrSampleCode","thumb-down"],["缺少我需要的資訊/範例","missingTheInformationSamplesINeed","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],[],[[["\u003cp\u003eThis page provides code samples demonstrating how to look up a single entity in Datastore mode.\u003c/p\u003e\n"],["\u003cp\u003eThe code examples are available in multiple languages, including C#, Go, Java, Node.js, PHP, Python, and Ruby.\u003c/p\u003e\n"],["\u003cp\u003eEach language section includes instructions on installing and using the Datastore mode client library and setting up authentication.\u003c/p\u003e\n"],["\u003cp\u003eThe code uses the \u003ccode\u003elookup\u003c/code\u003e, \u003ccode\u003eget\u003c/code\u003e, or \u003ccode\u003efind\u003c/code\u003e methods, depending on the language, to retrieve an entity using its key.\u003c/p\u003e\n"],["\u003cp\u003eThe page also directs users to the respective API reference documentation for each language and a sample browser for other Google Cloud product code examples.\u003c/p\u003e\n"]]],[],null,["# Lookup\n\nLooks up a single entity.\n\nExplore further\n---------------\n\n\nFor detailed documentation that includes this code sample, see the following:\n\n- [Entities, Properties, and Keys](/datastore/docs/concepts/entities)\n\nCode sample\n-----------\n\n### C#\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode C# API\nreference documentation](https://cloud.google.com/dotnet/docs/reference/Google.Cloud.Datastore.V1/latest).\n\n\nTo authenticate to Datastore mode, 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 Entity task = _db.Lookup(_sampleTask.Key);\n\n### Go\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode Go API\nreference documentation](https://cloud.google.com/go/docs/reference/cloud.google.com/go/datastore/latest).\n\n\nTo authenticate to Datastore mode, 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 var task Task\n taskKey := datastore.NameKey(\"Task\", \"sampleTask\", nil)\n err := client.Get(ctx, taskKey, &task)\n\n### Java\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode Java API\nreference documentation](https://cloud.google.com/java/docs/reference/google-cloud-datastore/latest/history).\n\n\nTo authenticate to Datastore mode, 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 Entity task = datastore.get(taskKey);\n\n### Node.js\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode Node.js API\nreference documentation](https://cloud.google.com/nodejs/docs/reference/datastore/latest).\n\n\nTo authenticate to Datastore mode, 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 taskKey = datastore.key('Task');\n const [entity] = await datastore.get(taskKey);\n // entity = {\n // category: 'Personal',\n // done: false,\n // priority: 4,\n // description: 'Learn Cloud Datastore',\n // [Symbol(KEY)]:\n // Key {\n // namespace: undefined,\n // id: '...',\n // kind: 'Task',\n // path: [Getter]\n // }\n // }\n // };\n console.log(entity);\n\n### PHP\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode PHP API\nreference documentation](https://googleapis.github.io/google-cloud-php/#/docs/cloud-datastore/latest).\n\n\nTo authenticate to Datastore mode, 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 $task = $datastore-\u003elookup($key);\n\n### Python\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode Python API\nreference documentation](https://cloud.google.com/python/docs/reference/datastore/latest).\n\n\nTo authenticate to Datastore mode, 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 from google.cloud import https://cloud.google.com/python/docs/reference/datastore/latest/\n\n # For help authenticating your client, visit\n # https://cloud.google.com/docs/authentication/getting-started\n client = https://cloud.google.com/python/docs/reference/datastore/latest/.https://cloud.google.com/python/docs/reference/datastore/latest/google.cloud.datastore.client.Client.html()\n\n key = client.https://cloud.google.com/python/docs/reference/datastore/latest/google.cloud.datastore.client.Client.html#google_cloud_datastore_client_Client_key(\"Task\", \"sampleTask\")\n task = client.https://cloud.google.com/python/docs/reference/datastore/latest/google.cloud.datastore.client.Client.html#google_cloud_datastore_client_Client_get(key)\n\n### Ruby\n\n\nTo learn how to install and use the client library for Datastore mode, see\n[Datastore mode client libraries](/datastore/docs/reference/libraries).\n\n\nFor more information, see the\n[Datastore mode Ruby API\nreference documentation](/ruby/docs/reference/google-cloud-datastore/latest).\n\n\nTo authenticate to Datastore mode, 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 # task_name = \"sampleTask\"\n task_key = datastore.key \"Task\", task_name\n task = datastore.find task_key\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=datastore)."]]