フィルタを使用した読み取り
コレクションでコンテンツを整理
必要に応じて、コンテンツの保存と分類を行います。
フィルタを使用して、指定された列の最新の値を読み取ります。
もっと見る
このコードサンプルを含む詳細なドキュメントについては、以下をご覧ください。
コードサンプル
特に記載のない限り、このページのコンテンツはクリエイティブ・コモンズの表示 4.0 ライセンスにより使用許諾されます。コードサンプルは Apache 2.0 ライセンスにより使用許諾されます。詳しくは、Google Developers サイトのポリシーをご覧ください。Java は Oracle および関連会社の登録商標です。
[[["わかりやすい","easyToUnderstand","thumb-up"],["問題の解決に役立った","solvedMyProblem","thumb-up"],["その他","otherUp","thumb-up"]],[["わかりにくい","hardToUnderstand","thumb-down"],["情報またはサンプルコードが不正確","incorrectInformationOrSampleCode","thumb-down"],["必要な情報 / サンプルがない","missingTheInformationSamplesINeed","thumb-down"],["翻訳に関する問題","translationIssue","thumb-down"],["その他","otherDown","thumb-down"]],[],[[["\u003cp\u003eThis page provides code samples demonstrating how to read the most recent value in a given column using a filter in Google Cloud Bigtable.\u003c/p\u003e\n"],["\u003cp\u003eCode examples are available in C++, C#, Java, Node.js, Python, and Ruby, each showcasing how to read and filter data.\u003c/p\u003e\n"],["\u003cp\u003eThe samples use Bigtable client libraries and require setting up Application Default Credentials for authentication.\u003c/p\u003e\n"],["\u003cp\u003eThe provided code examples illustrate how to implement the reading of table rows in their respective language, with specific logic for reading the cells and filtering.\u003c/p\u003e\n"],["\u003cp\u003eFor further code samples related to other Google cloud products, the Google Cloud sample browser is a resource.\u003c/p\u003e\n"]]],[],null,["Read the most recent value in a given column using a filter.\n\nExplore further\n\n\nFor detailed documentation that includes this code sample, see the following:\n\n- [C# hello world](/bigtable/docs/samples-c-sharp-hello)\n- [C++ hello world](/bigtable/docs/samples-cpp-hello)\n- [Node.js hello world](/bigtable/docs/samples-nodejs-hello)\n- [Python hello world](/bigtable/docs/samples-python-hello)\n- [Ruby hello world](/bigtable/docs/samples-ruby-hello)\n\nCode sample \n\nC++\n\n\nTo learn how to install and use the client library for Bigtable, see\n[Bigtable client libraries](/bigtable/docs/reference/libraries).\n\n\nTo authenticate to Bigtable, 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 for (auto& row : table.ReadRows(cbt::RowRange::InfiniteRange(),\n cbt::Filter::PassAllFilter())) {\n if (!row) throw std::move(row).status();\n std::cout \u003c\u003c row-\u003erow_key() \u003c\u003c \":\\n\";\n for (cbt::Cell const& c : row-\u003ecells()) {\n std::cout \u003c\u003c \"\\t\" \u003c\u003c c.family_name() \u003c\u003c \":\" \u003c\u003c c.column_qualifier()\n \u003c\u003c \" @ \" \u003c\u003c c.timestamp().count() \u003c\u003c \"us\\n\"\n \u003c\u003c \"\\t\\\"\" \u003c\u003c c.value() \u003c\u003c '\"' \u003c\u003c \"\\n\";\n }\n }\n\nC#\n\n\nTo learn how to install and use the client library for Bigtable, see\n[Bigtable client libraries](/bigtable/docs/reference/libraries).\n\n\nTo authenticate to Bigtable, 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 Console.WriteLine(\"Read all rows using streaming\");\n // stream the content of the whole table. Apply a filter to return latest only cell values accross all rows.\n ReadRowsStream responseRead = bigtableClient.ReadRows(tableName, filter: filter);\n\n Task printRead = PrintReadRowsAsync();\n printRead.Wait();\n\n async Task PrintReadRowsAsync()\n {\n var responseEnumerator = responseRead.GetAsyncEnumerator(default);\n while (await responseEnumerator.MoveNextAsync())\n {\n Row row = responseEnumerator.Current;\n Console.WriteLine(\n $\"\\tRow key: {row.Key.ToStringUtf8()} \" +\n $\" -- Value: {row.Families[0].Columns[0].Cells[0].Value.ToStringUtf8(),-16} \" +\n $\" -- Time Stamp: {row.Families[0].Columns[0].Cells[0].TimestampMicros}\");\n }\n }\n\nJava\n\n\nTo learn how to install and use the client library for Bigtable, see\n[Bigtable client libraries](/bigtable/docs/reference/libraries).\n\n\nTo authenticate to Bigtable, 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 private void readFilter(String tableId, Filter filter) {\n Query query = Query.create(TableId.of(tableId)).filter(filter);\n ServerStream\u003cRow\u003e rows = dataClient.readRows(query);\n for (Row row : rows) {\n printRow(row);\n }\n System.out.println(\"Table filter completed.\");\n }\n\nNode.js\n\n\nTo learn how to install and use the client library for Bigtable, see\n[Bigtable client libraries](/bigtable/docs/reference/libraries).\n\n\nTo authenticate to Bigtable, 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 console.log('Reading the entire table');\n // Note: For improved performance in production applications, call\n // `Table#readStream` to get a stream of rows. See the API documentation:\n // https://cloud.google.com/nodejs/docs/reference/bigtable/latest/Table#createReadStream\n const [allRows] = await table.getRows({filter});\n for (const row of allRows) {\n console.log(`\\tRead: ${getRowGreeting(row)}`);\n }\n\nPython\n\n\nTo learn how to install and use the client library for Bigtable, see\n[Bigtable client libraries](/bigtable/docs/reference/libraries).\n\n\nTo authenticate to Bigtable, 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 print(\"Scanning for all greetings:\")\n partial_rows = table.read_rows(filter_=row_filter)\n\n for row in partial_rows:\n cell = row.cells[column_family_id][column][0]\n print(cell.value.decode(\"utf-8\"))\n\nRuby\n\n\nTo learn how to install and use the client library for Bigtable, see\n[Bigtable client libraries](/bigtable/docs/reference/libraries).\n\n\nTo authenticate to Bigtable, 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 puts \"Reading the entire table\"\n table.read_rows.each do |row|\n puts \"Row key: #{row.key}, Value: #{row.cells[column_family].first.value}\"\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=bigtable)."]]