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读取示例

Cloud Bigtable 客户端库提供从表格中读取数据的功能。本页面提供各种类型读取请求多种语言版本的示例。如需查看概览，请参阅读取。

Bigtable 的 Python 客户端库提供两个 API，asyncio 和同步 API。如果您的应用是异步的，请使用 asyncio。

所需的角色

如需获得从表中读取数据所需的权限，请让您的管理员为您授予表的 Bigtable Reader (roles/bigtable.reader) IAM 角色。如需详细了解如何授予角色，请参阅管理对项目、文件夹和组织的访问权限。

您也可以通过自定义角色或其他预定义角色来获取所需的权限。

读取一行

以下代码示例展示如何使用行键获取单行数据。

Go

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，请参阅为客户端库设置身份验证。

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
}

HBase

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，请参阅为客户端库设置身份验证。

/**
 * Example of reading an individual row key.
 */
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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));

    byte[] rowkey = Bytes.toBytes("phone#4c410523#20190501");

    Result row = table.get(new Get(rowkey));
    printRow(row);

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

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，请参阅为客户端库设置身份验证。

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());
  }
}

Python asyncio

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，请参阅为客户端库设置身份验证。

from google.cloud.bigtable.data import BigtableDataClientAsync

async def read_row(project_id, instance_id, table_id):
    async with BigtableDataClientAsync(project=project_id) as client:
        async with client.get_table(instance_id, table_id) as table:
            row_key = "phone#4c410523#20190501"
            row = await table.read_row(row_key)
            print(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，请参阅为客户端库设置身份验证。

def read_row(project_id, instance_id, table_id):
    from google.cloud import bigtable

    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)

C#

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，请参阅为客户端库设置身份验证。


/// <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);
}

C++

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，请参阅为客户端库设置身份验证。

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);
}

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，请参阅为客户端库设置身份验证。

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，请参阅为客户端库设置身份验证。

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);
}

Ruby

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，请参阅为客户端库设置身份验证。

  # 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

读取部分行

以下代码示例展示如何从行中获取特定列。

Go

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，请参阅为客户端库设置身份验证。

func readRowPartial(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, bigtable.RowFilter(bigtable.ColumnFilter("os_build")))
	if err != nil {
		return fmt.Errorf("could not read row with key %s: %w", rowKey, err)
	}

	printRow(w, row)

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。

/**
 * Example of reading a subset of the columns for a single row.
 */
public static void readRowPartial() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readRowPartial(projectId, instanceId, tableId);
}

public static void readRowPartial(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));
    byte[] rowkey = Bytes.toBytes("phone#4c410523#20190501");

    Result row =
        table.get(
            new Get(rowkey).addColumn(Bytes.toBytes("stats_summary"), Bytes.toBytes("os_build")));
    printRow(row);

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

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，请参阅为客户端库设置身份验证。

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

public static void readRowPartial(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";
    Filters.Filter filter =
        FILTERS
            .chain()
            .filter(FILTERS.family().exactMatch("stats_summary"))
            .filter(FILTERS.qualifier().exactMatch("os_build"));

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

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

Python asyncio

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，请参阅为客户端库设置身份验证。

from google.cloud.bigtable.data import BigtableDataClientAsync
from google.cloud.bigtable.data import row_filters

async def read_row_partial(project_id, instance_id, table_id):
    async with BigtableDataClientAsync(project=project_id) as client:
        async with client.get_table(instance_id, table_id) as table:
            row_key = "phone#4c410523#20190501"
            col_filter = row_filters.ColumnQualifierRegexFilter(b"os_build")

            row = await table.read_row(row_key, row_filter=col_filter)
            print(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，请参阅为客户端库设置身份验证。

def read_row_partial(project_id, instance_id, table_id):
    from google.cloud import bigtable
    from google.cloud.bigtable import row_filters

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

    row_key = "phone#4c410523#20190501"
    col_filter = row_filters.ColumnQualifierRegexFilter(b"os_build")

    row = table.read_row(row_key, filter_=col_filter)
    print_row(row)

C#

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，请参阅为客户端库设置身份验证。


/// <summary>
/// /// Reads part of 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 ReadRowPartial(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);
    string rowkey = "phone#4c410523#20190501";
    RowFilter filter = RowFilters.ColumnQualifierExact("os_build");
    Row row = bigtableClient.ReadRow(tableName, rowkey, filter);
    return PrintRow(row);
}

C++

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，请参阅为客户端库设置身份验证。

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::ColumnName("stats_summary", "os_build"));
  if (!tuple) throw std::move(tuple).status();
  if (!tuple->first) {
    std::cout << "Row " << row_key << " not found\n";
    return;
  }
  PrintRow(tuple->second);
}

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，请参阅为客户端库设置身份验证。

const COLUMN_FAMILY = 'stats_summary';
const COLUMN_QUALIFIER = 'os_build';
const rowkey = 'phone#4c410523#20190501';

const [row] = await table
  .row(rowkey)
  .get([`${COLUMN_FAMILY}:${COLUMN_QUALIFIER}`]);

printRow(rowkey, row);

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，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;
use Google\Cloud\Bigtable\Filter;

/**
 * Read partial row data
 *
 * @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_partial(
    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';
    $rowFilter = Filter::qualifier()->regex('os_build');
    $row = $table->readRow($rowkey, ['filter' => $rowFilter]);

    print_row($rowkey, $row);
}

Ruby

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，请参阅为客户端库设置身份验证。

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

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

读取多行

以下代码示例展示如何使用一组行键获取多行数据。

Go

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，请参阅为客户端库设置身份验证。

func readRows(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)
	err = tbl.ReadRows(ctx, bigtable.RowList{"phone#4c410523#20190501", "phone#4c410523#20190502"},
		func(row bigtable.Row) bool {
			printRow(w, row)
			return true
		},
	)
	if err != nil {
		return fmt.Errorf("tbl.ReadRows: %w", err)
	}

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。


/**
 * Example of reading multiple row keys.
 */
public static void readRows() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readRows(projectId, instanceId, tableId);
}

public static void readRows(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));
    List<Get> queryRowList = new ArrayList<Get>();
    queryRowList.add(new Get(Bytes.toBytes("phone#4c410523#20190501")));
    queryRowList.add(new Get(Bytes.toBytes("phone#4c410523#20190502")));

    Result[] rows = table.get(queryRowList);

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

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，请参阅为客户端库设置身份验证。

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

public static void readRows(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)) {
    Query query =
        Query.create(TableId.of(tableId))
            .rowKey("phone#4c410523#20190501")
            .rowKey("phone#4c410523#20190502");
    ServerStream<Row> rows = dataClient.readRows(query);
    for (Row row : rows) {
      printRow(row);
    }
  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

Python asyncio

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，请参阅为客户端库设置身份验证。

from google.cloud.bigtable.data import BigtableDataClientAsync
from google.cloud.bigtable.data import ReadRowsQuery

async def read_rows(project_id, instance_id, table_id):
    async with BigtableDataClientAsync(project=project_id) as client:
        async with client.get_table(instance_id, table_id) as table:

            query = ReadRowsQuery(
                row_keys=[b"phone#4c410523#20190501", b"phone#4c410523#20190502"]
            )
            async for row in await table.read_rows_stream(query):
                print(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，请参阅为客户端库设置身份验证。

def read_rows(project_id, instance_id, table_id):
    from google.cloud import bigtable
    from google.cloud.bigtable.row_set import RowSet

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

    row_set = RowSet()
    row_set.add_row_key(b"phone#4c410523#20190501")
    row_set.add_row_key(b"phone#4c410523#20190502")

    rows = table.read_rows(row_set=row_set)
    for row in rows:
        print_row(row)

C#

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，请参阅为客户端库设置身份验证。



/// <summary>
/// /// Reads multiple rows 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 async Task<string> ReadRows(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);

    RowSet rowSet = RowSet.FromRowKeys("phone#4c410523#20190501", "phone#4c410523#20190502");
    ReadRowsStream readRowsStream = bigtableClient.ReadRows(tableName, rowSet);

    string result = "";
    await foreach(var row in readRowsStream)
    {
        result += PrintRow(row);
    }

    return result;
}

C++

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，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](cbt::Table table) {
  // Read and print the rows.
  for (StatusOr<cbt::Row>& row : table.ReadRows(
           cbt::RowSet("phone#4c410523#20190501", "phone#4c410523#20190502"),
           cbt::Filter::PassAllFilter())) {
    if (!row) throw std::move(row).status();
    PrintRow(*row);
  }
}

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，请参阅为客户端库设置身份验证。

const rowKeys = ['phone#4c410523#20190501', 'phone#4c410523#20190502'];
const [rows] = await table.getRows({keys: rowKeys});
rows.forEach(row => printRow(row.id, 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，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;

/**
 * Read rows using an array of keys
 *
 * @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_rows(
    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);

    $rows = $table->readRows(
        ['rowKeys' => ['phone#4c410523#20190501', 'phone#4c410523#20190502']]
    );

    foreach ($rows as $key => $row) {
        print_row($key, $row);
    }
}

Ruby

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，请参阅为客户端库设置身份验证。

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

table.read_rows(keys: ["phone#4c410523#20190501", "phone#4c410523#20190502"]).each do |row|
  print_row row
end

读取一个范围内的行

以下代码示例展示如何使用起始键和结束键获取多行数据。

Go

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，请参阅为客户端库设置身份验证。

func readRowRange(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)
	err = tbl.ReadRows(ctx, bigtable.NewRange("phone#4c410523#20190501", "phone#4c410523#201906201"),
		func(row bigtable.Row) bool {
			printRow(w, row)
			return true
		},
	)

	if err != nil {
		return fmt.Errorf("tbl.ReadRows: %w", err)
	}

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。


/**
 * Example of reading a range of rows using a key range.
 */
public static void readRowRange() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readRowRange(projectId, instanceId, tableId);
}

public static void readRowRange(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));

    Scan rangeQuery =
        new Scan()
            .withStartRow(Bytes.toBytes("phone#4c410523#20190501"))
            .withStopRow(Bytes.toBytes("phone#4c410523#201906201"));

    ResultScanner rows = table.getScanner(rangeQuery);

    for (Result row : rows) {
      printRow(row);
    }

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

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，请参阅为客户端库设置身份验证。

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

public static void readRowRange(String projectId, String instanceId, String tableId) {
  String start = "phone#4c410523#20190501";
  String end = "phone#4c410523#201906201";

  // 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)) {
    Query query = Query.create(TableId.of(tableId)).range(start, end);
    ServerStream<Row> rows = dataClient.readRows(query);
    for (Row row : rows) {
      printRow(row);
    }
  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

Python asyncio

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，请参阅为客户端库设置身份验证。

from google.cloud.bigtable.data import BigtableDataClientAsync
from google.cloud.bigtable.data import ReadRowsQuery
from google.cloud.bigtable.data import RowRange

async def read_row_range(project_id, instance_id, table_id):
    async with BigtableDataClientAsync(project=project_id) as client:
        async with client.get_table(instance_id, table_id) as table:

            row_range = RowRange(
                start_key=b"phone#4c410523#20190501",
                end_key=b"phone#4c410523#201906201",
            )
            query = ReadRowsQuery(row_ranges=[row_range])

            async for row in await table.read_rows_stream(query):
                print(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，请参阅为客户端库设置身份验证。

def read_row_range(project_id, instance_id, table_id):
    from google.cloud import bigtable
    from google.cloud.bigtable.row_set import RowSet

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

    row_set = RowSet()
    row_set.add_row_range_from_keys(
        start_key=b"phone#4c410523#20190501", end_key=b"phone#4c410523#201906201"
    )

    rows = table.read_rows(row_set=row_set)
    for row in rows:
        print_row(row)

C#

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，请参阅为客户端库设置身份验证。


/// <summary>
/// /// Reads a range of rows 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 async Task<string> ReadRowRange(string projectId = "YOUR-PROJECT-ID", string instanceId = "YOUR-INSTANCE-ID", string tableId = "YOUR-TABLE-ID")
{
    string start = "phone#4c410523#20190501";
    string end = "phone#4c410523#201906201";

    BigtableClient bigtableClient = BigtableClient.Create();
    TableName tableName = new TableName(projectId, instanceId, tableId);
    RowSet rowSet = RowSet.FromRowRanges(RowRange.ClosedOpen(start, end));
    ReadRowsStream readRowsStream = bigtableClient.ReadRows(tableName, rowSet);

    string result = "";
    await foreach (var row in readRowsStream)
    {
        result += PrintRow(row);
    }

    return result;
}

C++

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，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](cbt::Table table) {
  // Read and print the rows.
  for (StatusOr<cbt::Row>& row :
       table.ReadRows(cbt::RowRange::Range("phone#4c410523#20190501",
                                           "phone#4c410523#201906201"),
                      cbt::Filter::PassAllFilter())) {
    if (!row) throw std::move(row).status();
    PrintRow(*row);
  }
}

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，请参阅为客户端库设置身份验证。

const start = 'phone#4c410523#20190501';
const end = 'phone#4c410523#201906201';

await table
  .createReadStream({
    start,
    end,
  })
  .on('error', err => {
    // Handle the error.
    console.log(err);
  })
  .on('data', row => printRow(row.id, row.data))
  .on('end', () => {
    // All rows retrieved.
  });

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，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;

/**
 * Read using a range for row keys
 *
 * @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_range(
    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);

    $rows = $table->readRows([
        'rowRanges' => [
            [
                'startKeyClosed' => 'phone#4c410523#20190501',
                'endKeyOpen' => 'phone#4c410523#201906201'
            ]
        ]
    ]);

    foreach ($rows as $key => $row) {
        print_row($key, $row);
    }
}

Ruby

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，请参阅为客户端库设置身份验证。

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

range = table.new_row_range.between "phone#4c410523#20190501", "phone#4c410523#201906201"
table.read_rows(ranges: range).each do |row|
  print_row row
end

读取多个范围内的行

以下代码示例展示如何使用多个开始键和结束键获取多行数据。请注意，在单个请求中请求大量的行范围可能会影响读取性能。

Go

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，请参阅为客户端库设置身份验证。

func readRowRanges(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)
	err = tbl.ReadRows(ctx, bigtable.RowRangeList{
		bigtable.NewRange("phone#4c410523#20190501", "phone#4c410523#201906201"),
		bigtable.NewRange("phone#5c10102#20190501", "phone#5c10102#201906201"),
	},
		func(row bigtable.Row) bool {
			printRow(w, row)
			return true
		},
	)
	if err != nil {
		return fmt.Errorf("tbl.ReadRows: %w", err)
	}

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。

/**
 * Example of reading multiple disjoint row ranges.
 */
public static void readRowRanges() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readRowRanges(projectId, instanceId, tableId);
}

public static void readRowRanges(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));
    List<RowRange> ranges = new ArrayList<>();

    ranges.add(
        new RowRange(
            Bytes.toBytes("phone#4c410523#20190501"),
            true,
            Bytes.toBytes("phone#4c410523#20190601"),
            false));
    ranges.add(
        new RowRange(
            Bytes.toBytes("phone#5c10102#20190501"),
            true,
            Bytes.toBytes("phone#5c10102#20190601"),
            false));
    Filter filter = new MultiRowRangeFilter(ranges);
    Scan scan = new Scan().setFilter(filter);

    ResultScanner rows = table.getScanner(scan);

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

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，请参阅为客户端库设置身份验证。

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

public static void readRowRanges(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)) {
    Query query =
        Query.create(TableId.of(tableId))
            .range("phone#4c410523#20190501", "phone#4c410523#20190601")
            .range("phone#5c10102#20190501", "phone#5c10102#20190601");
    ServerStream<Row> rows = dataClient.readRows(query);
    for (Row row : rows) {
      printRow(row);
    }
  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

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，请参阅为客户端库设置身份验证。

def read_row_ranges(project_id, instance_id, table_id):
    from google.cloud import bigtable
    from google.cloud.bigtable.row_set import RowSet

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

    row_set = RowSet()
    row_set.add_row_range_from_keys(
        start_key=b"phone#4c410523#20190501", end_key=b"phone#4c410523#201906201"
    )
    row_set.add_row_range_from_keys(
        start_key=b"phone#5c10102#20190501", end_key=b"phone#5c10102#201906201"
    )

    rows = table.read_rows(row_set=row_set)
    for row in rows:
        print_row(row)

C#

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，请参阅为客户端库设置身份验证。


/// <summary>
/// /// Reads multiple ranges of rows 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 async Task<string> ReadRowRanges(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);
    RowSet rowSet = RowSet.FromRowRanges(RowRange.ClosedOpen("phone#4c410523#20190501", "phone#4c410523#20190601"),
    RowRange.ClosedOpen("phone#5c10102#20190501", "phone#5c10102#20190601"));
    ReadRowsStream readRowsStream = bigtableClient.ReadRows(tableName, rowSet);

    string result = "";
    await foreach (var row in readRowsStream)
    {
        result += PrintRow(row);
    }

    return result;
}

C++

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，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](cbt::Table table) {
  // Read and print the rows.
  for (StatusOr<cbt::Row>& row : table.ReadRows(
           cbt::RowSet({cbt::RowRange::Range("phone#4c410523#20190501",
                                             "phone#4c410523#20190601"),
                        cbt::RowRange::Range("phone#5c10102#20190501",
                                             "phone#5c10102#20190601")}),
           cbt::Filter::PassAllFilter())) {
    if (!row) throw std::move(row).status();
    PrintRow(*row);
  }
}

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，请参阅为客户端库设置身份验证。

await table
  .createReadStream({
    ranges: [
      {
        start: 'phone#4c410523#20190501',
        end: 'phone#4c410523#20190601',
      },
      {
        start: 'phone#5c10102#20190501',
        end: 'phone#5c10102#20190601',
      },
    ],
  })
  .on('error', err => {
    // Handle the error.
    console.log(err);
  })
  .on('data', row => printRow(row.id, row.data))
  .on('end', () => {
    // All rows retrieved.
  });

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，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;

/**
 * Read using multiple ranges for row keys
 *
 * @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_ranges(
    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);

    $rows = $table->readRows([
        'rowRanges' => [
            [
                'startKeyClosed' => 'phone#4c410523#20190501',
                'endKeyOpen' => 'phone#4c410523#201906201'
            ],
            [
                'startKeyClosed' => 'phone#5c10102#20190501',
                'endKeyOpen' => 'phone#5c10102#201906201'
            ]
        ]
    ]);

    foreach ($rows as $key => $row) {
        print_row($key, $row);
    }
}

Ruby

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，请参阅为客户端库设置身份验证。

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

ranges = []
ranges <<
  table.new_row_range.between("phone#4c410523#20190501", "phone#4c410523#201906201") <<
  table.new_row_range.between("phone#5c10102#20190501", "phone#5c10102#201906201")
table.read_rows(ranges: ranges).each do |row|
  print_row row
end

使用行键前缀读取多行

以下代码示例展示如何使用行键前缀获取多行数据。

Go

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，请参阅为客户端库设置身份验证。

func readPrefix(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)
	err = tbl.ReadRows(ctx, bigtable.PrefixRange("phone#"),
		func(row bigtable.Row) bool {
			printRow(w, row)
			return true
		},
	)
	if err != nil {
		return fmt.Errorf("tbl.ReadRows: %w", err)
	}

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。


/**
 * Example of reading a range of rows using a row prefix.
 */
public static void readPrefix() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readPrefix(projectId, instanceId, tableId);
}

public static void readPrefix(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));
    Scan prefixScan = new Scan().setRowPrefixFilter(Bytes.toBytes("phone"));
    ResultScanner rows = table.getScanner(prefixScan);

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

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，请参阅为客户端库设置身份验证。

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

public static void readPrefix(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)) {
    Query query = Query.create(TableId.of(tableId)).prefix("phone");
    ServerStream<Row> rows = dataClient.readRows(query);
    for (Row row : rows) {
      printRow(row);
    }
  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

Python asyncio

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，请参阅为客户端库设置身份验证。

from google.cloud.bigtable.data import BigtableDataClientAsync
from google.cloud.bigtable.data import ReadRowsQuery
from google.cloud.bigtable.data import RowRange

async def read_prefix(project_id, instance_id, table_id):
    async with BigtableDataClientAsync(project=project_id) as client:
        async with client.get_table(instance_id, table_id) as table:

            prefix = "phone#"
            end_key = prefix[:-1] + chr(ord(prefix[-1]) + 1)
            prefix_range = RowRange(start_key=prefix, end_key=end_key)
            query = ReadRowsQuery(row_ranges=[prefix_range])

            async for row in await table.read_rows_stream(query):
                print(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，请参阅为客户端库设置身份验证。

def read_prefix(project_id, instance_id, table_id):
    from google.cloud import bigtable
    from google.cloud.bigtable.row_set import RowSet

    client = bigtable.Client(project=project_id, admin=True)
    instance = client.instance(instance_id)
    table = instance.table(table_id)
    prefix = "phone#"
    end_key = prefix[:-1] + chr(ord(prefix[-1]) + 1)

    row_set = RowSet()
    row_set.add_row_range_from_keys(prefix.encode("utf-8"), end_key.encode("utf-8"))

    rows = table.read_rows(row_set=row_set)
    for row in rows:
        print_row(row)

C#

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，请参阅为客户端库设置身份验证。


/// <summary>
/// /// Reads rows starting with a prefix 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 async Task<string> ReadPrefix(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);

    string prefix = "phone";
    char prefixEndChar = prefix[prefix.Length - 1];
    prefixEndChar++;
    string end = prefix.Substring(0, prefix.Length - 1) + prefixEndChar;
    RowSet rowSet = RowSet.FromRowRanges(RowRange.Closed(prefix, end));
    ReadRowsStream readRowsStream = bigtableClient.ReadRows(tableName, rowSet);

    string result = "";
    await foreach (var row in readRowsStream)
    {
        result += PrintRow(row);
    }

    return result;
}

C++

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，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](cbt::Table table) {
  // Read and print the rows.
  for (StatusOr<cbt::Row>& row : table.ReadRows(
           cbt::RowRange::Prefix("phone"), cbt::Filter::PassAllFilter())) {
    if (!row) throw std::move(row).status();
    PrintRow(*row);
  }
}

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，请参阅为客户端库设置身份验证。

const prefix = 'phone#';

await table
  .createReadStream({
    prefix,
  })
  .on('error', err => {
    // Handle the error.
    console.log(err);
  })
  .on('data', row => printRow(row.id, row.data))
  .on('end', () => {
    // All rows retrieved.
  });

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，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;

/**
 * Read using a row key prefix
 *
 * @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_prefix(
    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);

    $prefix = 'phone#';
    $end = $prefix;
    // Increment the last character of the prefix so the filter matches everything in between
    $end[-1] = chr(
        ord($end[-1]) + 1
    );

    $rows = $table->readRows([
        'rowRanges' => [
            [
                'startKeyClosed' => $prefix,
                'endKeyClosed' => $end,
            ]
        ]
    ]);

    foreach ($rows as $key => $row) {
        print_row($key, $row);
    }
}

Ruby

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，请参阅为客户端库设置身份验证。

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

prefix = "phone#"
end_key = prefix[0...-1] + prefix[-1].next
range = table.new_row_range.between prefix, end_key
table.read_rows(ranges: range).each do |row|
  print_row row
end

反向扫描

以下代码示例展示了如何反向扫描。如需了解详情，请参阅反向扫描。为避免效率低下，请将反向扫描限制为约 50 行。

Go

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，请参阅为客户端库设置身份验证。

func readRowsReversed(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)
	err = tbl.ReadRows(ctx, bigtable.NewRange("phone#5c10102", "phone#5c10103"),
		func(row bigtable.Row) bool {
			printRow(w, row)
			return true
		},
		bigtable.ReverseScan())
	if err != nil {
		return fmt.Errorf("tbl.ReadRows: %w", err)
	}

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。

/**
 * Example of reading a range of rows in reverse order.
 */
public static void readRowsReversed() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readRowsReversed(projectId, instanceId, tableId);
}

public static void readRowsReversed(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));
    Scan revScan =
        new Scan()
            .setReversed(true)
            .setLimit(2)
            .withStartRow(Bytes.toBytes("phone#4c410523#20190505"));
    ResultScanner rows = table.getScanner(revScan);

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

Java

由于此示例使用前缀以及开始和结束行键，因此它将返回两个过滤条件的并集的结果。

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，请参阅为客户端库设置身份验证。

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

public static void readRowsReversed(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)) {
    Query query =
        Query.create(TableId.of(tableId))
            .reversed(true)
            .limit(3)
            .prefix("phone#4c410523")
            .range("phone#5c10102", "phone#5c10103");
    ServerStream<Row> rows = dataClient.readRows(query);
    for (Row row : rows) {
      printRow(row);
    }
  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

C++

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，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::Options;
using ::google::cloud::StatusOr;
[](cbt::Table table) {
  // Read and print the rows.
  auto reader = table.ReadRows(
      cbt::RowRange::RightOpen("phone#5c10102", "phone#5c10103"), 3,
      cbt::Filter::PassAllFilter(),
      Options{}.set<cbt::ReverseScanOption>(true));
  for (StatusOr<cbt::Row>& row : reader) {
    if (!row) throw std::move(row).status();
    PrintRow(*row);
  }
}

使用过滤条件读取

以下代码示例展示如何使用行过滤条件获取多行数据。如需详细了解您可以在读取请求中使用的过滤条件类型，请参阅过滤条件概览。此外，我们还提供了其他代码示例，其中以多种语言展示如何实现各种类型的过滤条件。

Go

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，请参阅为客户端库设置身份验证。

func readFilter(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)
	err = tbl.ReadRows(ctx, bigtable.RowRange{},
		func(row bigtable.Row) bool {
			printRow(w, row)
			return true
		},
		bigtable.RowFilter(bigtable.ValueFilter("PQ2A.*$")),
	)
	if err != nil {
		return fmt.Errorf("tbl.ReadRows: %w", err)
	}

	return nil
}

HBase

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，请参阅为客户端库设置身份验证。


/**
 * Example of filtering row contents using filters.
 */
public static void readFilter() {
  // TODO(developer): Replace these variables before running the sample.
  String projectId = "my-project-id";
  String instanceId = "my-instance-id";
  String tableId = "mobile-time-series";
  readFilter(projectId, instanceId, tableId);
}

public static void readFilter(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.
  try (Connection connection = BigtableConfiguration.connect(projectId, instanceId)) {
    Table table = connection.getTable(TableName.valueOf(tableId));

    ValueFilter valueFilter =
        new ValueFilter(CompareOp.EQUAL, new RegexStringComparator("PQ2A.*"));
    Scan scan = new Scan().setFilter(valueFilter);

    ResultScanner rows = table.getScanner(scan);

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

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，请参阅为客户端库设置身份验证。

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

public static void readFilter(String projectId, String instanceId, String tableId) {
  Filters.Filter filter = FILTERS.value().regex("PQ2A.*");

  // 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)) {
    Query query = Query.create(TableId.of(tableId)).filter(filter);
    ServerStream<Row> rows = dataClient.readRows(query);
    for (Row row : rows) {
      printRow(row);
    }
  } catch (IOException e) {
    System.out.println(
        "Unable to initialize service client, as a network error occurred: \n" + e.toString());
  }
}

Python asyncio

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，请参阅为客户端库设置身份验证。

from google.cloud.bigtable.data import BigtableDataClientAsync
from google.cloud.bigtable.data import ReadRowsQuery
from google.cloud.bigtable.data import row_filters

async def read_with_filter(project_id, instance_id, table_id):
    async with BigtableDataClientAsync(project=project_id) as client:
        async with client.get_table(instance_id, table_id) as table:

            row_filter = row_filters.ValueRegexFilter(b"PQ2A.*$")
            query = ReadRowsQuery(row_filter=row_filter)

            async for row in await table.read_rows_stream(query):
                print(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，请参阅为客户端库设置身份验证。

def read_filter(project_id, instance_id, table_id):
    from google.cloud import bigtable
    from google.cloud.bigtable import row_filters

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

    rows = table.read_rows(filter_=row_filters.ValueRegexFilter(b"PQ2A.*$"))
    for row in rows:
        print_row(row)

C#

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，请参阅为客户端库设置身份验证。


/// <summary>
/// /// Reads using a filter 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 async Task<string> ReadFilter(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);

    RowFilter filter = RowFilters.ValueRegex("PQ2A.*");

    ReadRowsStream readRowsStream = bigtableClient.ReadRows(tableName, filter: filter);
    string result = "";
    await foreach (var row in readRowsStream)
    {
        result += PrintRow(row);
    }

    return result;
}

C++

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，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](cbt::Table table) {
  // Read and print the rows.
  for (StatusOr<cbt::Row>& row :
       table.ReadRows(cbt::RowRange::InfiniteRange(),
                      cbt::Filter::ValueRegex("PQ2A.*"))) {
    if (!row) throw std::move(row).status();
    PrintRow(*row);
  }
}

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，请参阅为客户端库设置身份验证。

const filter = {
  value: /PQ2A.*$/,
};

await table
  .createReadStream({
    filter,
  })
  .on('error', err => {
    // Handle the error.
    console.log(err);
  })
  .on('data', row => printRow(row.id, row.data))
  .on('end', () => {
    // All rows retrieved.
  });

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，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\BigtableClient;
use Google\Cloud\Bigtable\Filter;

/**
 * Read using a filter
 *
 * @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_filter(
    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);

    $rowFilter = Filter::value()->regex('PQ2A.*$');

    $rows = $table->readRows([
        'filter' => $rowFilter
    ]);

    foreach ($rows as $key => $row) {
        print_row($key, $row);
    }
}

Ruby

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，请参阅为客户端库设置身份验证。

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

filter = Google::Cloud::Bigtable::RowFilter.value "PQ2A.*$"
table.read_rows(filter: filter).each do |row|
  print_row row
end

从授权视图读取数据

以下示例展示了如何向已获授权的视图发送读取请求。语法与从表中读取类似，但您还必须提供已获授权的视图 ID。

Java

此示例展示了如何从已获授权的视图中读取单行。

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，请参阅为客户端库设置身份验证。

try {
  System.out.println("\nReading a single row by row key from an authorized view");
  Row row =
      dataClient.readRow(AuthorizedViewId.of(tableId, authorizedViewId), ROW_KEY_PREFIX + 0);
  System.out.println("Row: " + row.getKey().toStringUtf8());
  for (RowCell cell : row.getCells()) {
    System.out.printf(
        "Family: %s    Qualifier: %s    Value: %s%n",
        cell.getFamily(), cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
  }
  return row;
} catch (NotFoundException e) {
  System.err.println("Failed to read from a non-existent authorized view: " + e.getMessage());
  return null;
}

此示例展示了如何使用过滤器从已获授权的视图读取数据。

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，请参阅为客户端库设置身份验证。

try {
  // A filter that matches only the most recent cell within each column
  Filter filter = FILTERS.limit().cellsPerColumn(1);
  System.out.println("\nScanning authorized view with filter");
  Query query = Query.create(AuthorizedViewId.of(tableId, authorizedViewId)).filter(filter);
  ServerStream<Row> rowStream = dataClient.readRows(query);
  List<Row> authorizedViewRows = new ArrayList<>();
  for (Row r : rowStream) {
    System.out.println("Row Key: " + r.getKey().toStringUtf8());
    authorizedViewRows.add(r);
    for (RowCell cell : r.getCells()) {
      System.out.printf(
          "Family: %s    Qualifier: %s    Value: %s%n",
          cell.getFamily(), cell.getQualifier().toStringUtf8(), cell.getValue().toStringUtf8());
    }
  }
  return authorizedViewRows;
} catch (NotFoundException e) {
  System.err.println("Failed to read a non-existent authorized view: " + e.getMessage());
  return null;
}