Read examples

Cloud Bigtable client libraries provide the ability to read data from a table. This page provides examples of each type of read request in multiple languages. For an overview, see Reads.

The Python client library for Bigtable offers two APIs, asyncio and a synchronous API. If your application is asynchronous, use asyncio.

Required roles

To get the permissions that you need to read data from a table, ask your administrator to grant you the Bigtable reader (roles/bigtable.reader) IAM role on the table. For more information about granting roles, see Manage access to projects, folders, and organizations.

You might also be able to get the required permissions through custom roles or other predefined roles.

Read a single row

The following code samples show how to get a single row of data using the row key.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

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

PHP

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

  # 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

Read a partial row

The following code samples show how to get specific columns from a row.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

  # 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

Read multiple rows

The following code samples show how to get multiple rows of data using a set of row keys.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

const rowKeys = ['phone#4c410523#20190501', 'phone#4c410523#20190502'];
const [rows] = await table.getRows({keys: rowKeys});
rows.forEach(row => printRow(row.id, row.data));

PHP

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

# 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

Read a range of rows

The following code samples show how to get multiple rows of data using a start key and an end key.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

# 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

Read multiple ranges of rows

The following code samples show how to get multiple rows of data using multiple start key and end keys. Be aware that requesting a large number of row ranges in a single request can have an impact on read performance.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

# 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

Read multiple rows using a row key prefix

The following code samples show how to get multiple rows of data using a row key prefix.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

# 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

Scan in reverse

The following code samples show how to scan in reverse. See the details at Reverse scans. To avoid inefficiency, limit a reverse scan to about 50 rows.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

Because this example uses a prefix and start and end row keys, it returns a result from the union of those two filters.

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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);
  }
}

Read with filters

The following code samples show how to get multiple rows of data using a row filter. To learn more about the types of filters that you can use in read requests, see the overview of filters. Additional code samples showing how to implement various types of filters in multiple languages are also available.

Note: The HBase client for Java uses HBase's filter APIs instead of the Bigtable Data API. To learn about HBase's filter APIs, see the HBase documentation.

Go

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/**
 * 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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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#

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

/// <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++

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

# 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

Read from an authorized view

The following examples show how to send a read request to an authorized view. The syntax is similar to reading from a table except you must also provide the authorized view ID.

Java

This example shows how to read a single row from an authorized view.

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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;
}

This example shows how to read from an authorized view with a filter.

To learn how to install and use the client library for Bigtable, see Bigtable client libraries.

To authenticate to Bigtable, set up Application Default Credentials. For more information, see Set up authentication for client libraries.

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;
}

What's next

• Learn more about reading data.
• Explore the types of filters that you can use.
• Review code samples that show how to implement filters.
• Read about Bigtable writes.
• Use the Bigtable emulator.