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读取行

读取行。

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如需查看包含此代码示例的详细文档，请参阅以下内容：

读取示例

代码示例

C++

如需了解如何安装和使用 Bigtable 客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](google::cloud::bigtable::Table table, std::string const& row_key) {
  StatusOr<std::pair<bool, cbt::Row>> tuple =
      table.ReadRow(row_key, cbt::Filter::PassAllFilter());
  if (!tuple) throw std::move(tuple).status();
  if (!tuple->first) {
    std::cout << "Row " << row_key << " not found\n";
    return;
  }
  PrintRow(tuple->second);
}

C#

如需了解如何安装和使用 Bigtable 客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。


/// <summary>
/// /// Reads one row from an existing table.
///</summary>
/// <param name="projectId">Your Google Cloud Project ID.</param>
/// <param name="instanceId">Your Google Cloud Bigtable Instance ID.</param>
/// <param name="tableId">Your Google Cloud Bigtable table ID.</param>
public string ReadRow(
    string projectId = "YOUR-PROJECT-ID", string instanceId = "YOUR-INSTANCE-ID", string tableId = "YOUR-TABLE-ID")
{
    BigtableClient bigtableClient = BigtableClient.Create();
    TableName tableName = new TableName(projectId, instanceId, tableId);
    Row row = bigtableClient.ReadRow(tableName, rowKey: "phone#4c410523#20190501");

    return PrintRow(row);
}

Go

如需了解如何安装和使用 Bigtable 客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

func readRow(w io.Writer, projectID, instanceID string, tableName string) error {
	// projectID := "my-project-id"
	// instanceID := "my-instance-id"
	// tableName := "mobile-time-series"

	ctx := context.Background()
	client, err := bigtable.NewClient(ctx, projectID, instanceID)
	if err != nil {
		return fmt.Errorf("bigtable.NewClient: %w", err)
	}
	defer client.Close()

	tbl := client.Open(tableName)
	rowKey := "phone#4c410523#20190501"
	row, err := tbl.ReadRow(ctx, rowKey)
	if err != nil {
		return fmt.Errorf("could not read row with key %s: %w", rowKey, err)
	}

	printRow(w, row)
	return nil
}

Java

如需了解如何安装和使用 Bigtable 的客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

public static void readRow() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readRow(projectId, instanceId, tableId);
}

public static void readRow(String projectId, String instanceId, String tableId) {
  // Initialize client that will be used to send requests. This client only needs to be created
  // once, and can be reused for multiple requests. After completing all of your requests, call
  // the "close" method on the client to safely clean up any remaining background resources.
  try (BigtableDataClient dataClient = BigtableDataClient.create(projectId, instanceId)) {
    String rowkey = "phone#4c410523#20190501";

    Row row = dataClient.readRow(TableId.of(tableId), rowkey);
    printRow(row);

  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

Node.js

如需了解如何安装和使用 Bigtable 的客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

const rowkey = 'phone#4c410523#20190501';

const [row] = await table.row(rowkey).get();
printRow(rowkey, row.data);

PHP

如需了解如何安装和使用 Bigtable 的客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;

/**
 * Read a row using the row key
 *
 * @param string $projectId The Google Cloud project ID
 * @param string $instanceId The ID of the Bigtable instance
 * @param string $tableId The ID of the table to read from
 */
function read_row(
    string $projectId,
    string $instanceId,
    string $tableId
): void {
    // Connect to an existing table with an existing instance.
    $dataClient = new BigtableClient([
        'projectId' => $projectId,
    ]);
    $table = $dataClient->table($instanceId, $tableId);

    $rowkey = 'phone#4c410523#20190501';
    $row = $table->readRow($rowkey);

    print_row($rowkey, $row);
}

Python

如需了解如何安装和使用 Bigtable 的客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

def read_row(project_id, instance_id, table_id):
    client = bigtable.Client(project=project_id, admin=True)
    instance = client.instance(instance_id)
    table = instance.table(table_id)

    row_key = "phone#4c410523#20190501"

    row = table.read_row(row_key)
    print_row(row)

Ruby

如需了解如何安装和使用 Bigtable 客户端库，请参阅 Bigtable 客户端库。

如需向 Bigtable 进行身份验证，请设置应用默认凭据。如需了解详情，请参阅为本地开发环境设置身份验证。

  # instance_id = "my-instance"
  # table_id    = "my-table"
  bigtable = Google::Cloud::Bigtable.new
  table = bigtable.table instance_id, table_id

  row = table.read_row "phone#4c410523#20190501"
  print_row row
end

后续步骤

如需搜索和过滤其他 Google Cloud 产品的代码示例，请参阅 Google Cloud 示例浏览器。