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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 provides code samples in Go, Java, and Python for reading data from a Bigtable database using row keys.\u003c/p\u003e\n"],["\u003cp\u003eThe code examples demonstrate how to read a single row using a specific row key in all three mentioned languages.\u003c/p\u003e\n"],["\u003cp\u003eThe Java example illustrates reading specific cells by specifying the column family and qualifier.\u003c/p\u003e\n"],["\u003cp\u003eThe page directs you to resources for installing the Bigtable client library and setting up authentication credentials.\u003c/p\u003e\n"],["\u003cp\u003eYou can access other code samples for other Google Cloud products via the Google Cloud sample browser, as mentioned at the end.\u003c/p\u003e\n"]]],[],null,["Read using a noncontiguous set of row keys.\n\nExplore further\n\n\nFor detailed documentation that includes this code sample, see the following:\n\n- [Go hello world](/bigtable/docs/samples-go-hello)\n- [Java hello world](/bigtable/docs/samples-java-hello-world)\n\nCode sample \n\nGo\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 log.Printf(\"Getting a single greeting by row key:\")\n row, err := tbl.ReadRow(ctx, rowKeys[0], bigtable.RowFilter(bigtable.ColumnFilter(columnName)))\n if err != nil {\n \tlog.Fatalf(\"Could not read row with key %s: %v\", rowKeys[0], err)\n }\n log.Printf(\"\\t%s = %s\\n\", rowKeys[0], string(row[columnFamilyName][0].Value))\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 try {\n System.out.println(\"\\nReading a single row by row key\");\n Row row = dataClient.readRow(TableId.of(tableId), ROW_KEY_PREFIX + 0);\n System.out.println(\"Row: \" + row.getKey().toStringUtf8());\n for (RowCell cell : row.getCells()) {\n System.out.printf(\n \"Family: %s Qualifier: %s Value: %s%n\",\n cell.getFamily(), cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());\n }\n return row;\n } catch (NotFoundException e) {\n System.err.println(\"Failed to read from a non-existent table: \" + e.getMessage());\n return null;\n }\n try {\n System.out.println(\"\\nReading specific cells by family and qualifier\");\n Row row = dataClient.readRow(TableId.of(tableId), ROW_KEY_PREFIX + 0);\n System.out.println(\"Row: \" + row.getKey().toStringUtf8());\n List\u003cRowCell\u003e cells = row.getCells(COLUMN_FAMILY, COLUMN_QUALIFIER_NAME);\n for (RowCell cell : cells) {\n System.out.printf(\n \"Family: %s Qualifier: %s Value: %s%n\",\n cell.getFamily(), cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());\n }\n return cells;\n } catch (NotFoundException e) {\n System.err.println(\"Failed to read from a non-existent table: \" + e.getMessage());\n return null;\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(\"Getting a single greeting by row key.\")\n key = \"greeting0\".encode()\n\n row = table.read_row(key, row_filter)\n cell = row.cells[column_family_id][column][0]\n print(cell.value.decode(\"utf-8\"))\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)."]]