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[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],[],[],[],null,["Read data.\n\nExplore further\n\n\nFor detailed documentation that includes this code sample, see the following:\n\n- [Getting started with Spanner in C++](/spanner/docs/getting-started/cpp)\n- [Getting started with Spanner in Go](/spanner/docs/getting-started/go)\n- [Getting started with Spanner in Java](/spanner/docs/getting-started/java)\n- [Getting started with Spanner in Node.js](/spanner/docs/getting-started/nodejs)\n- [Getting started with Spanner in PHP](/spanner/docs/getting-started/php)\n- [Getting started with Spanner in Python](/spanner/docs/getting-started/python)\n- [Getting started with Spanner in Ruby](/spanner/docs/getting-started/ruby)\n- [Reads outside of transactions](/spanner/docs/reads)\n\nCode sample \n\nC++\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, 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 void ReadData(google::cloud::spanner::Client client) {\n namespace spanner = ::google::cloud::spanner;\n\n auto rows = client.Read(\"Albums\", google::cloud::spanner::KeySet::All(),\n {\"SingerId\", \"AlbumId\", \"AlbumTitle\"});\n using RowType = std::tuple\u003cstd::int64_t, std::int64_t, std::string\u003e;\n for (auto& row : spanner::StreamOf\u003cRowType\u003e(rows)) {\n if (!row) throw std::move(row).status();\n std::cout \u003c\u003c \"SingerId: \" \u003c\u003c std::get\u003c0\u003e(*row) \u003c\u003c \"\\t\";\n std::cout \u003c\u003c \"AlbumId: \" \u003c\u003c std::get\u003c1\u003e(*row) \u003c\u003c \"\\t\";\n std::cout \u003c\u003c \"AlbumTitle: \" \u003c\u003c std::get\u003c2\u003e(*row) \u003c\u003c \"\\n\";\n }\n\n std::cout \u003c\u003c \"Read completed for [spanner_read_data]\\n\";\n }\n\nGo\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, 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\n import (\n \t\"context\"\n \t\"fmt\"\n \t\"io\"\n\n \t\"cloud.google.com/go/spanner\"\n \t\"google.golang.org/api/iterator\"\n )\n\n func read(w io.Writer, db string) error {\n \tctx := context.Background()\n \tclient, err := spanner.NewClient(ctx, db)\n \tif err != nil {\n \t\treturn err\n \t}\n \tdefer client.Close()\n\n \titer := client.https://cloud.google.com/go/docs/reference/cloud.google.com/go/spanner/latest/index.html#cloud_google_com_go_spanner_Client_Single().Read(ctx, \"Albums\", spanner.https://cloud.google.com/go/docs/reference/cloud.google.com/go/spanner/latest/index.html#cloud_google_com_go_spanner_KeySet_AllKeys(),\n \t\t[]string{\"SingerId\", \"AlbumId\", \"AlbumTitle\"})\n \tdefer iter.Stop()\n \tfor {\n \t\trow, err := iter.Next()\n \t\tif err == iterator.Done {\n \t\t\treturn nil\n \t\t}\n \t\tif err != nil {\n \t\t\treturn err\n \t\t}\n \t\tvar singerID, albumID int64\n \t\tvar albumTitle string\n \t\tif err := row.https://cloud.google.com/go/docs/reference/cloud.google.com/go/spanner/latest/index.html#cloud_google_com_go_spanner_Row_Columns(&singerID, &albumID, &albumTitle); err != nil {\n \t\t\treturn err\n \t\t}\n \t\tfmt.Fprintf(w, \"%d %d %s\\n\", singerID, albumID, albumTitle)\n \t}\n }\n\nJava\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, 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 static void read(DatabaseClient dbClient) {\n try (ResultSet resultSet =\n dbClient\n .singleUse()\n .read(\n \"Albums\",\n KeySet.all(), // Read all rows in a table.\n Arrays.asList(\"SingerId\", \"AlbumId\", \"AlbumTitle\"))) {\n while (resultSet.next()) {\n System.out.printf(\n \"%d %d %s\\n\", resultSet.getLong(0), resultSet.getLong(1), resultSet.getString(2));\n }\n }\n }\n\nNode.js\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, 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 // Imports the Google Cloud client library\n const {Spanner} = require('https://cloud.google.com/nodejs/docs/reference/spanner/latest/overview.html');\n\n /**\n * TODO(developer): Uncomment the following lines before running the sample.\n */\n // const projectId = 'my-project-id';\n // const instanceId = 'my-instance';\n // const databaseId = 'my-database';\n\n // Creates a client\n const spanner = new https://cloud.google.com/nodejs/docs/reference/spanner/latest/spanner/spanner.html({\n projectId: projectId,\n });\n\n // Gets a reference to a Cloud Spanner instance and database\n const instance = spanner.instance(instanceId);\n const database = instance.database(databaseId);\n\n // Reads rows from the Albums table\n const albumsTable = database.table('Albums');\n\n const query = {\n columns: ['SingerId', 'AlbumId', 'AlbumTitle'],\n keySet: {\n all: true,\n },\n };\n\n try {\n const [rows] = await albumsTable.read(query);\n\n rows.forEach(row =\u003e {\n const json = row.toJSON();\n console.log(\n `SingerId: ${json.SingerId}, AlbumId: ${json.AlbumId}, AlbumTitle: ${json.AlbumTitle}`,\n );\n });\n } catch (err) {\n console.error('ERROR:', err);\n } finally {\n // Close the database when finished.\n await database.close();\n }\n\nPHP\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, set up Application Default Credentials.\nFor more information, see\n\n[Set up authentication for a local development environment](/docs/authentication/set-up-adc-local-dev-environment).\n\n use Google\\Cloud\\Spanner\\SpannerClient;\n\n /**\n * Reads sample data from the database.\n * Example:\n * ```\n * read_data($instanceId, $databaseId);\n * ```\n *\n * @param string $instanceId The Spanner instance ID.\n * @param string $databaseId The Spanner database ID.\n */\n function read_data(string $instanceId, string $databaseId): void\n {\n $spanner = new SpannerClient();\n $instance = $spanner-\u003einstance($instanceId);\n $database = $instance-\u003edatabase($databaseId);\n\n $keySet = $spanner-\u003ekeySet(['all' =\u003e true]);\n $results = $database-\u003eread(\n 'Albums',\n $keySet,\n ['SingerId', 'AlbumId', 'AlbumTitle']\n );\n\n foreach ($results-\u003erows() as $row) {\n printf('SingerId: %s, AlbumId: %s, AlbumTitle: %s' . PHP_EOL,\n $row['SingerId'], $row['AlbumId'], $row['AlbumTitle']);\n }\n }\n\nPython\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, 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 def read_data(instance_id, database_id):\n \"\"\"Reads sample data from the database.\"\"\"\n spanner_client = spanner.Client()\n instance = spanner_client.instance(instance_id)\n database = instance.database(database_id)\n\n with database.snapshot() as snapshot:\n keyset = spanner.KeySet(all_=True)\n results = snapshot.read(\n table=\"Albums\", columns=(\"SingerId\", \"AlbumId\", \"AlbumTitle\"), keyset=keyset\n )\n\n for row in results:\n print(\"SingerId: {}, AlbumId: {}, AlbumTitle: {}\".format(*row))\n\nRuby\n\n\nTo learn how to install and use the client library for Spanner, see\n[Spanner client libraries](/spanner/docs/reference/libraries).\n\n\nTo authenticate to Spanner, 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 # project_id = \"Your Google Cloud project ID\"\n # instance_id = \"Your Spanner instance ID\"\n # database_id = \"Your Spanner database ID\"\n\n require \"google/cloud/spanner\"\n\n spanner = Google::Cloud::https://cloud.google.com/ruby/docs/reference/activerecord-spanner-adapter/latest/Google-Cloud-Spanner.html.new project: project_id\n client = spanner.https://cloud.google.com/ruby/docs/reference/google-cloud-spanner/latest/Google-Cloud-Spanner-Project.html instance_id, database_id\n\n client.read(\"Albums\", [:SingerId, :AlbumId, :AlbumTitle]).rows.https://cloud.google.com/ruby/docs/reference/google-cloud-spanner/latest/Google-Cloud-Spanner-BatchWriteResults.html do |row|\n puts \"#{row[:SingerId]} #{row[:AlbumId]} #{row[:AlbumTitle]}\"\n end\n\nWhat's next\n\n\nTo search and filter code samples for other Google Cloud products, see the\n[Google Cloud sample browser](/docs/samples?product=spanner)."]]
