配置垃圾回收

本页面介绍了如何在 Google Cloud 控制台中查看、设置和更新垃圾回收政策。 Bigtable。在阅读本页面内容之前，您应该先熟悉垃圾回收。

在使用 cbt CLI ，请按照设置说明（包括创建 .cbtrc 文件的步骤）进行操作。

查看当前的垃圾回收政策

您可以使用 Google Cloud 控制台或 cbt CLI 查看 列族的垃圾回收政策。

控制台

如需查看列族的当前垃圾回收政策，请执行以下操作：

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击表所在行中的 修改。

5. 点击要查看的列族旁边的 打开。

6. 查看完垃圾回收政策后，点击取消以退出。

cbt

您可以通过运行以下命令并用有效的表 ID 替换 TABLE_ID 来查找给定表的当前垃圾回收政策：

cbt ls TABLE_ID

设置垃圾回收政策

您可以使用 Google Cloud 控制台、cbt CLI 或 Cloud Bigtable 客户端库设置垃圾回收政策。

根据存在时间回收垃圾

以下部分示例展示了如何设置列族中数据的最长存在时间。

控制台

要为列族中的单元设置到期时间，请执行以下操作：

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击 “修改”。

5. 点击要修改的列族旁边的 打开。

6. 选择基于存在时间的政策。

7. 在存在时间上限字段中输入数字，并使用单位下拉菜单选择时间单位。

   例如，要将列族的数据保留 30 分钟，请输入 30 并选择分钟。

8. 点击保存。

cbt

以下示例会创建一个名为 cf1 的列族，然后将列族中数据的最长存在时间设置为 5 天。这会指示 Bigtable 移除此列族的所有列中时间戳超过 5 天的所有数据。

cbt createfamily your-table cf1
cbt setgcpolicy your-table cf1 maxage=5d

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。

import (
	"context"
	"fmt"
	"io"
	"time"

	"cloud.google.com/go/bigtable"
)

func createFamilyGCMaxAge(w io.Writer, projectID, instanceID string, tableName string) error {
	// projectID := "my-project-id"
	// instanceID := "my-instance-id"
	// tableName := "my-table-name"

	ctx := context.Background()

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

	columnFamilyName := "cf1"
	if err := adminClient.CreateColumnFamily(ctx, tableName, columnFamilyName); err != nil {
		return fmt.Errorf("CreateColumnFamily(%s): %w", columnFamilyName, err)
	}

	// Set a garbage collection policy of 5 days.
	maxAge := time.Hour * 24 * 5
	policy := bigtable.MaxAgePolicy(maxAge)
	if err := adminClient.SetGCPolicy(ctx, tableName, columnFamilyName, policy); err != nil {
		return fmt.Errorf("SetGCPolicy(%s): %w", policy, err)
	}

	fmt.Fprintf(w, "created column family %s with policy: %v\n", columnFamilyName, policy)
	return nil
}

Java

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Creates a column family with GC policy : maximum age
// where age = current time minus cell timestamp

// Defines the GC rule to retain data with max age of 5 days.
DurationRule maxAgeRule = GCRULES.maxAge(5, TimeUnit.DAYS);

// Creates column family with given GC rule.
try {
  // ModifyColumnFamiliesRequest can be used both for adding and modifying families, here it is
  // being used to add a family
  ModifyColumnFamiliesRequest columnFamiliesRequest =
      ModifyColumnFamiliesRequest.of(tableId).addFamily(COLUMN_FAMILY_1, maxAgeRule);
  adminClient.modifyFamilies(columnFamiliesRequest);
  System.out.println("Created column family: " + COLUMN_FAMILY_1);
} catch (AlreadyExistsException e) {
  System.err.println(
      "Failed to create column family with rule, already exists: " + e.getMessage());
}

Python

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

    print("Creating column family cf1 with with MaxAge GC Rule...")
    # Create a column family with GC policy : maximum age
    # where age = current time minus cell timestamp

    # Define the GC rule to retain data with max age of 5 days
    max_age_rule = column_family.MaxAgeGCRule(datetime.timedelta(days=5))

    column_family1 = table.column_family("cf1", max_age_rule)
    column_family1.create()
    print("Created column family cf1 with MaxAge GC Rule.")

C#

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy : maximum age
// where age = current time minus cell timestamp
// Initialize request argument(s).
// Define the GC rule to retain data with max age of 5 days
GcRule MaxAgeRule = new GcRule { MaxAge = Duration.FromTimeSpan(TimeSpan.FromDays(5.0)) };

// Column family to create
ColumnFamily columnFamily = new ColumnFamily { GcRule = MaxAgeRule };

TableName tableName = new TableName(projectId, instanceId, tableId);

// Modification to create column family
ModifyColumnFamiliesRequest.Types.Modification modification = new ModifyColumnFamiliesRequest.Types.Modification
{
    Create = columnFamily,
    Id = "cf1"
};

ModifyColumnFamiliesRequest request = new ModifyColumnFamiliesRequest
{
    TableName = tableName,
    Modifications = { modification }
};
try
{
    // Make the request
    Table response = bigtableTableAdminClient.ModifyColumnFamilies(request);
    Console.WriteLine("Created column family");
    // Print table information.
    GetTable(tableId);
}
catch (Exception ex)
{
    Console.WriteLine($"Error creating column family {ex.Message}");
}

C++

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
namespace cbta = ::google::cloud::bigtable_admin;
using ::google::bigtable::admin::v2::ModifyColumnFamiliesRequest;
using ::google::cloud::StatusOr;
[](cbta::BigtableTableAdminClient admin, std::string const& project_id,
   std::string const& instance_id, std::string const& table_id,
   std::string const& family_name) {
  std::string table_name = cbt::TableName(project_id, instance_id, table_id);
  auto constexpr kSecondsPerDay =
      std::chrono::seconds(std::chrono::hours(24)).count();

  ModifyColumnFamiliesRequest::Modification mod;
  mod.set_id(family_name);
  mod.mutable_create()->mutable_gc_rule()->mutable_max_age()->set_seconds(
      5 * kSecondsPerDay);

  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(table_name, {std::move(mod)});

  if (!schema) throw std::move(schema).status();
  std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}

Node.js

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy : maximum age
// where age = current time minus cell timestamp

// Define the GC rule to retain data with max age of 5 days
const maxAgeRule = {
  rule: {
    age: {
      // Value must be atleast 1 millisecond
      seconds: 60 * 60 * 24 * 5,
      nanos: 0,
    },
  },
};

let [family] = await table.createFamily('cf1', maxAgeRule);
console.log(`Created column family ${family.id}`);

PHP

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Protobuf\Duration;

/**
 * Create a new column family with a max age GC rule
 *
 * @param string $projectId The Google Cloud project ID
 * @param string $instanceId The ID of the Bigtable instance where the table resides
 * @param string $tableId The ID of the table in which the rule needs to be created
 */
function create_family_gc_max_age(
    string $projectId,
    string $instanceId,
    string $tableId
): void {
    $tableAdminClient = new BigtableTableAdminClient();

    $tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

    print('Creating column family cf1 with MaxAge GC Rule...' . PHP_EOL);
    // Create a column family with GC policy : maximum age
    // where age = current time minus cell timestamp

    $columnFamily1 = new ColumnFamily();
    $duration = new Duration();
    $duration->setSeconds(3600 * 24 * 5);
    $MaxAgeRule = (new GcRule())->setMaxAge($duration);
    $columnFamily1->setGcRule($MaxAgeRule);

    $columnModification = new Modification();
    $columnModification->setId('cf1');
    $columnModification->setCreate($columnFamily1);
    $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
        ->setName($tableName)
        ->setModifications([$columnModification]);
    $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);
    print('Created column family cf1 with MaxAge GC Rule.' . PHP_EOL);
}

Ruby

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

# Create a column family with GC policy : maximum age
# where age = current time minus cell timestamp
# NOTE: Age value must be atleast 1 millisecond
max_age_rule = Google::Cloud::Bigtable::GcRule.max_age 60 * 60 * 24 * 5
column_families = table.column_families do |cfs|
  cfs.add "cf1", gc_rule: max_age_rule
end
family = column_families["cf1"]

根据版本数回收垃圾

以下部分介绍如何创建具有说明要保留的数据版本数或单元格数的垃圾回收政策的列族。

控制台

如需设置要在列族中保留的单元（版本）数，请执行以下操作：

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击表所在行中的 修改。

5. 点击要修改的列族旁边的 打开。

6. 选择基于版本的政策。

7. 输入列族中每列要保留的单元格数量。

8. 点击保存。

cbt

此示例会创建一个名为 cf2 的列族，然后将列族的版本数设置为二。这会指示 Bigtable 移除此列族的所有列中的所有单元，两个最新单元除外。

cbt createfamily your-table cf2
cbt setgcpolicy your-table cf2 maxversions=2

此示例设置了相关政策以移除最新单元之外的所有单元。

cbt setgcpolicy your-table cf2 maxversions=1

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。

import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/bigtable"
)

func createFamilyGCMaxVersions(w io.Writer, projectID, instanceID string, tableName string) error {
	// projectID := "my-project-id"
	// instanceID := "my-instance-id"
	// tableName := "my-table-name"

	ctx := context.Background()

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

	columnFamilyName := "cf2"
	if err := adminClient.CreateColumnFamily(ctx, tableName, columnFamilyName); err != nil {
		return fmt.Errorf("CreateColumnFamily(%s): %w", columnFamilyName, err)
	}

	// Set a garbage collection policy of 2 versions.
	policy := bigtable.MaxVersionsPolicy(2)
	if err := adminClient.SetGCPolicy(ctx, tableName, columnFamilyName, policy); err != nil {
		return fmt.Errorf("SetGCPolicy(%s): %w", policy, err)
	}

	fmt.Fprintf(w, "created column family %s with policy: %v\n", columnFamilyName, policy)
	return nil
}

Java

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Creates a column family with GC policy : most recent N versions
// where 1 = most recent version

// Defines the GC policy to retain only the most recent 2 versions.
VersionRule versionRule = GCRULES.maxVersions(2);

// Creates column family with given GC rule.
try {
  // ModifyColumnFamiliesRequest can be used both for adding and modifying families, here it is
  // being used to add a family
  ModifyColumnFamiliesRequest columnFamiliesRequest =
      ModifyColumnFamiliesRequest.of(tableId).addFamily(COLUMN_FAMILY_2, versionRule);
  adminClient.modifyFamilies(columnFamiliesRequest);
  System.out.println("Created column family: " + COLUMN_FAMILY_2);
} catch (AlreadyExistsException e) {
  System.err.println(
      "Failed to create column family with rule, already exists: " + e.getMessage());
}

Python

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

    print("Creating column family cf2 with max versions GC rule...")
    # Create a column family with GC policy : most recent N versions
    # where 1 = most recent version

    # Define the GC policy to retain only the most recent 2 versions
    max_versions_rule = column_family.MaxVersionsGCRule(2)

    column_family2 = table.column_family("cf2", max_versions_rule)
    column_family2.create()
    print("Created column family cf2 with Max Versions GC Rule.")

C#

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy : most recent N versions
// where 1 = most recent version
// Initialize request argument(s).
// Define the GC policy to retain only the most recent 2 versions
GcRule maxVersionsRule = new GcRule { MaxNumVersions = 2 };

// Column family to create
ColumnFamily columnFamily = new ColumnFamily { GcRule = maxVersionsRule };

TableName tableName = new TableName(projectId, instanceId, tableId);

// Modification to create column family
ModifyColumnFamiliesRequest.Types.Modification modification = new ModifyColumnFamiliesRequest.Types.Modification
{
    Create = columnFamily,
    Id = "cf2"
};

ModifyColumnFamiliesRequest request = new ModifyColumnFamiliesRequest
{
    TableName = tableName,
    Modifications = { modification }
};
try
{
    // Make the request
    Table response = bigtableTableAdminClient.ModifyColumnFamilies(request);
    Console.WriteLine("Created column family");
}
catch (Exception ex)
{
    Console.WriteLine($"Error creating column family {ex.Message}");
}

C++

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
namespace cbta = ::google::cloud::bigtable_admin;
using ::google::bigtable::admin::v2::ModifyColumnFamiliesRequest;
using ::google::cloud::StatusOr;
[](cbta::BigtableTableAdminClient admin, std::string const& project_id,
   std::string const& instance_id, std::string const& table_id,
   std::string const& family_name) {
  std::string table_name = cbt::TableName(project_id, instance_id, table_id);

  ModifyColumnFamiliesRequest::Modification mod;
  mod.set_id(family_name);
  mod.mutable_create()->mutable_gc_rule()->set_max_num_versions(2);

  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(table_name, {std::move(mod)});

  if (!schema) throw std::move(schema).status();
  std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}

Node.js

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy : most recent N versions
// where 1 = most recent version

// Define the GC policy to retain only the most recent 2 versions
const maxVersionsRule = {
  rule: {
    versions: 2,
  },
};

// Create a column family with given GC rule
[family] = await table.createFamily('cf2', maxVersionsRule);
console.log(`Created column family ${family.id}`);

PHP

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;

/**
 * Create a new column family with a max versions GC rule
 *
 * @param string $projectId The Google Cloud project ID
 * @param string $instanceId The ID of the Bigtable instance where the table resides
 * @param string $tableId The ID of the table in which the rule needs to be created
 */
function create_family_gc_max_versions(
    string $projectId,
    string $instanceId,
    string $tableId
): void {
    $tableAdminClient = new BigtableTableAdminClient();

    $tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

    print('Creating column family cf2 with max versions GC rule...' . PHP_EOL);
    $columnFamily2 = new ColumnFamily();
    $maxVersionRule = (new GcRule())->setMaxNumVersions(2);
    $columnFamily2->setGCRule($maxVersionRule);

    $columnModification = new Modification();
    $columnModification->setId('cf2');
    $columnModification->setCreate($columnFamily2);
    $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
        ->setName($tableName)
        ->setModifications([$columnModification]);
    $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);

    print('Created column family cf2 with Max Versions GC Rule.' . PHP_EOL);
}

Ruby

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

# Create a column family with GC policy : most recent N versions
# where 1 = most recent version
max_versions_rule = Google::Cloud::Bigtable::GcRule.max_versions 2
column_families = table.column_families do |cfs|
  cfs.add "cf2", gc_rule: max_versions_rule
end
family = column_families["cf2"]

根据多个条件回收垃圾

以下部分示例演示了如何创建具有交叉式垃圾回收政策的列族。

控制台

如需为列族中的单元格设置交叉式垃圾回收政策，请执行以下操作：

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击表所在行中的 修改。

5. 点击要修改的列族旁边的 打开。

6. 选择自定义政策。

7. 在文本区域中输入垃圾回收规则，为 maxage 和/或maxversions 设置值。可接受的存在时间单位包括 ms、s、m、h 和 d，代表毫秒、秒、分钟、小时和天。

   例如，如需移除存在时间超过 5 天且早于两个最新单元格的单元格，请输入以下内容。单元格必须符合两个条件才能移除。

   maxage=5d and maxversions=2
   

8. 点击保存。

cbt

此示例会创建一个名为 cf4 的列族，然后设置垃圾回收政策以移除特定单元格，这些单元格的存在时间超过五天且早于列族的所有列中的两个最新单元格。单元格必须符合两个条件才能移除。

cbt createfamily your-table cf4
cbt setgcpolicy your-table cf4 maxage=5d and maxversions=2

此示例将设置一项政策，以移除最新单元格之外所有存在时间超过 14 天的单元格。

cbt setgcpolicy your-table cf4 maxage=14d and maxversions=1

Go

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

import (
	"context"
	"fmt"
	"io"
	"time"

	"cloud.google.com/go/bigtable"
)

func createFamilyGCIntersect(w io.Writer, projectID, instanceID string, tableName string) error {
	// projectID := "my-project-id"
	// instanceID := "my-instance-id"
	// tableName := "my-table-name"

	ctx := context.Background()

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

	columnFamilyName := "cf4"
	if err := adminClient.CreateColumnFamily(ctx, tableName, columnFamilyName); err != nil {
		return fmt.Errorf("CreateColumnFamily(%s): %w", columnFamilyName, err)
	}

	// GC rule: Drop cells older than 5 days AND older than the most recent 2 versions
	maxAge := time.Hour * 24 * 5
	maxAgePolicy := bigtable.MaxAgePolicy(maxAge)
	policy := bigtable.IntersectionPolicy(bigtable.MaxVersionsPolicy(2), maxAgePolicy)
	if err := adminClient.SetGCPolicy(ctx, tableName, columnFamilyName, policy); err != nil {
		return fmt.Errorf("SetGCPolicy(%s): %w", policy, err)
	}

	fmt.Fprintf(w, "created column family %s with policy: %v\n", columnFamilyName, policy)
	return nil
}

Java

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Creates a column family with GC policy to drop data that matches all conditions.

// Defines a GC rule to drop cells older than 5 days AND older than the most recent 2 versions.
DurationRule maxAgeRule = GCRULES.maxAge(5, TimeUnit.DAYS);
VersionRule versionRule = GCRULES.maxVersions(2);
IntersectionRule intersectionRule = GCRULES.intersection().rule(maxAgeRule).rule(versionRule);

// Creates column family with given GC rule.
try {
  // ModifyColumnFamiliesRequest can be used both for adding and modifying families, here it is
  // being used to add a family
  ModifyColumnFamiliesRequest columnFamiliesRequest =
      ModifyColumnFamiliesRequest.of(tableId).addFamily(COLUMN_FAMILY_4, intersectionRule);
  adminClient.modifyFamilies(columnFamiliesRequest);
  System.out.println("Created column family: " + COLUMN_FAMILY_4);
} catch (AlreadyExistsException e) {
  System.err.println(
      "Failed to create column family with rule, already exists: " + e.getMessage());
}

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。

    print("Creating column family cf4 with Intersection GC rule...")
    # Create a column family with GC policy to drop data that matches
    # all conditions
    # GC rule: Drop cells older than 5 days AND older than the most
    # recent 2 versions
    intersection_rule = column_family.GCRuleIntersection(
        [
            column_family.MaxAgeGCRule(datetime.timedelta(days=5)),
            column_family.MaxVersionsGCRule(2),
        ]
    )

    column_family4 = table.column_family("cf4", intersection_rule)
    column_family4.create()
    print("Created column family cf4 with Intersection GC rule.")

C#

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy to drop data that matches all conditions.
// Initialize request argument(s).
// GC rule: Drop cells older than 5 days AND older than the most recent 2 versions.
GcRule.Types.Intersection intersectionRule = new GcRule.Types.Intersection
{
    Rules =
    {
        new GcRule { MaxNumVersions = 2 },
        new GcRule { MaxAge = Duration.FromTimeSpan(TimeSpan.FromDays(5)) }
    }
};
GcRule gcRule = new GcRule { Intersection = intersectionRule };

// Column family to create
ColumnFamily columnFamily = new ColumnFamily { GcRule = gcRule };

TableName tableName = new TableName(projectId, instanceId, tableId);

// Modification to create column family
ModifyColumnFamiliesRequest.Types.Modification modification = new ModifyColumnFamiliesRequest.Types.Modification
{
    Create = columnFamily,
    Id = "cf4"
};

ModifyColumnFamiliesRequest request = new ModifyColumnFamiliesRequest
{
    TableName = tableName,
    Modifications = { modification }
};
try
{
    // Make the request
    Table response = bigtableTableAdminClient.ModifyColumnFamilies(request);
    Console.WriteLine("Created column family");
}
catch (Exception ex)
{
    Console.WriteLine($"Error creating column family {ex.Message}");
}

C++

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
namespace cbta = ::google::cloud::bigtable_admin;
using ::google::bigtable::admin::v2::ModifyColumnFamiliesRequest;
using ::google::cloud::StatusOr;
[](cbta::BigtableTableAdminClient admin, std::string const& project_id,
   std::string const& instance_id, std::string const& table_id,
   std::string const& family_name) {
  std::string table_name = cbt::TableName(project_id, instance_id, table_id);
  auto constexpr kSecondsPerDay =
      std::chrono::seconds(std::chrono::hours(24)).count();

  ModifyColumnFamiliesRequest::Modification mod;
  mod.set_id(family_name);
  auto& gc_int =
      *mod.mutable_create()->mutable_gc_rule()->mutable_intersection();
  gc_int.add_rules()->set_max_num_versions(1);
  gc_int.add_rules()->mutable_max_age()->set_seconds(5 * kSecondsPerDay);

  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(table_name, {std::move(mod)});

  if (!schema) throw std::move(schema).status();
  std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}

Node.js

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy to drop data that matches all conditions

// GC rule: Drop cells older than 5 days AND older than the most recent 2 versions
const intersectionRule = {
  rule: {
    versions: 2,
    age: {
      seconds: 60 * 60 * 24 * 5,
      nanos: 0,
    },
    intersection: true,
  },
};
[family] = await table.createFamily('cf4', intersectionRule);
console.log(`Created column family ${family.id}`);

PHP

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
use Google\Cloud\Bigtable\Admin\V2\GcRule\Intersection as GcRuleIntersection;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Protobuf\Duration;

/**
 * Create a new column family with an intersection GC rule
 *
 * @param string $projectId The Google Cloud project ID
 * @param string $instanceId The ID of the Bigtable instance where the table resides
 * @param string $tableId The ID of the table in which the rule needs to be created
 */
function create_family_gc_intersection(
    string $projectId,
    string $instanceId,
    string $tableId
): void {
    $tableAdminClient = new BigtableTableAdminClient();

    $tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

    print('Creating column family cf4 with Intersection GC rule...' . PHP_EOL);
    $columnFamily4 = new ColumnFamily();

    $intersectionRule = new GcRuleIntersection();
    $intersectionArray = [
        (new GcRule())->setMaxAge((new Duration())->setSeconds(3600 * 24 * 5)),
        (new GcRule())->setMaxNumVersions(2)
    ];
    $intersectionRule->setRules($intersectionArray);

    $intersection = new GcRule();
    $intersection->setIntersection($intersectionRule);

    $columnFamily4->setGCRule($intersection);

    $columnModification = new Modification();
    $columnModification->setId('cf4');
    $columnModification->setCreate($columnFamily4);
    $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
        ->setName($tableName)
        ->setModifications([$columnModification]);
    $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);

    print('Created column family cf4 with Union GC rule' . PHP_EOL);
}

Ruby

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

# Create a column family with GC policy to drop data that matches at least
# one condition
max_age_rule = Google::Cloud::Bigtable::GcRule.max_age 60 * 60 * 24 * 5
max_versions_rule = Google::Cloud::Bigtable::GcRule.max_versions 2
intersection_gc_rule = Google::Cloud::Bigtable::GcRule.intersection max_age_rule, max_versions_rule
column_families = table.column_families do |cfs|
  cfs.add "cf4", gc_rule: intersection_gc_rule
end
family = column_families["cf4"]

以下部分介绍了如何创建具有联合式垃圾回收政策的列族。

控制台

如需为列族中的单元格设置联合式垃圾回收政策，请执行以下操作：

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击表所在行中的 修改。

5. 点击要修改的列族旁边的 打开。

6. 选择自定义政策。

7. 在文本区域中输入垃圾回收规则，为 maxage 和/或maxversions 设置值。可接受的存在时间单位包括 ms、s、m、h 和 d，代表毫秒、秒、分钟、小时和天。

   例如，如需移除存在时间超过 5 天或早于两个最新单元格的单元格，请输入以下内容。单元格必须符合任一条件才能移除。

   maxage=5d or maxversions=2
   

8. 点击保存。

cbt

此示例会创建一个名为 cf3 的列族，然后设置垃圾回收政策，以移除存在时间超过 5 天或早于两个最新单元格的单元格。单元格必须符合任一条件才能移除。

cbt createfamily your-table cf3
cbt setgcpolicy your-table cf3 maxage=5d or maxversions=2

此示例会设置政策以移除最新单元格值以外的所有单元格值，而且甚至会移除存在时间超过一秒钟的最新单元格。

cbt setgcpolicy your-table cf3 maxversions=1 or maxage=1s

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。

import (
	"context"
	"fmt"
	"io"
	"time"

	"cloud.google.com/go/bigtable"
)

func createFamilyGCUnion(w io.Writer, projectID, instanceID string, tableName string) error {
	// projectID := "my-project-id"
	// instanceID := "my-instance-id"
	// tableName := "my-table-name"

	ctx := context.Background()

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

	columnFamilyName := "cf3"
	if err := adminClient.CreateColumnFamily(ctx, tableName, columnFamilyName); err != nil {
		return fmt.Errorf("CreateColumnFamily(%s): %w", columnFamilyName, err)
	}

	// Define a GC rule to drop cells older than 5 days or not the most recent version
	maxAge := time.Hour * 24 * 5
	maxAgePolicy := bigtable.MaxAgePolicy(maxAge)
	policy := bigtable.UnionPolicy(bigtable.MaxVersionsPolicy(2), maxAgePolicy)
	if err := adminClient.SetGCPolicy(ctx, tableName, columnFamilyName, policy); err != nil {
		return fmt.Errorf("SetGCPolicy(%s): %w", policy, err)
	}

	fmt.Fprintf(w, "created column family %s with policy: %v\n", columnFamilyName, policy)
	return nil
}

Java

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Creates a column family with GC policy to drop data that matches at least one condition.

// Defines a list of GC rules to drop cells older than 5 days OR not the most recent
// version.
UnionRule unionRule =
    GCRULES.union().rule(GCRULES.maxAge(5, TimeUnit.DAYS)).rule(GCRULES.maxVersions(1));

// Creates column family with given GC rule.
try {
  // ModifyColumnFamiliesRequest can be used both for adding and modifying families, here it is
  // being used to add a family
  ModifyColumnFamiliesRequest columnFamiliesRequest =
      ModifyColumnFamiliesRequest.of(tableId).addFamily(COLUMN_FAMILY_3, unionRule);
  adminClient.modifyFamilies(columnFamiliesRequest);
  System.out.println("Created column family: " + COLUMN_FAMILY_3);
} catch (AlreadyExistsException e) {
  System.err.println(
      "Failed to create column family with rule, already exists: " + e.getMessage());
}

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。

    print("Creating column family cf3 with union GC rule...")
    # Create a column family with GC policy to drop data that matches
    # at least one condition.
    # Define a GC rule to drop cells older than 5 days or not the
    # most recent version
    union_rule = column_family.GCRuleUnion(
        [
            column_family.MaxAgeGCRule(datetime.timedelta(days=5)),
            column_family.MaxVersionsGCRule(2),
        ]
    )

    column_family3 = table.column_family("cf3", union_rule)
    column_family3.create()
    print("Created column family cf3 with Union GC rule")

C#

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy to drop data that matches at least one condition.
// Initialize request argument(s).
// Define a GC rule to drop cells older than 5 days or not the most recent version.
GcRule.Types.Union unionRule = new GcRule.Types.Union
{
    Rules =
    {
        new GcRule { MaxNumVersions = 1 },
        new GcRule { MaxAge = Duration.FromTimeSpan(TimeSpan.FromDays(5)) }
    }
};
GcRule gcRule = new GcRule { Union = unionRule };

// Column family to create
ColumnFamily columnFamily = new ColumnFamily { GcRule = gcRule };

TableName tableName = new TableName(projectId, instanceId, tableId);

// Modification to create column family
ModifyColumnFamiliesRequest.Types.Modification modification = new ModifyColumnFamiliesRequest.Types.Modification
{
    Create = columnFamily,
    Id = "cf3"
};

ModifyColumnFamiliesRequest request = new ModifyColumnFamiliesRequest
{
    TableName = tableName,
    Modifications = { modification }
};
try
{
    // Make the request
    Table response = bigtableTableAdminClient.ModifyColumnFamilies(request);
    Console.WriteLine("Created column family");
}
catch (Exception ex)
{
    Console.WriteLine($"Error creating column family {ex.Message}");
}

C++

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
namespace cbta = ::google::cloud::bigtable_admin;
using ::google::bigtable::admin::v2::ModifyColumnFamiliesRequest;
using ::google::cloud::StatusOr;
[](cbta::BigtableTableAdminClient admin, std::string const& project_id,
   std::string const& instance_id, std::string const& table_id,
   std::string const& family_name) {
  std::string table_name = cbt::TableName(project_id, instance_id, table_id);
  auto constexpr kSecondsPerDay =
      std::chrono::seconds(std::chrono::hours(24)).count();

  ModifyColumnFamiliesRequest::Modification mod;
  mod.set_id(family_name);
  auto& gc_union = *mod.mutable_create()->mutable_gc_rule()->mutable_union_();
  gc_union.add_rules()->set_max_num_versions(1);
  gc_union.add_rules()->mutable_max_age()->set_seconds(5 * kSecondsPerDay);

  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(table_name, {std::move(mod)});

  if (!schema) throw std::move(schema).status();
  std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}

Node.js

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a column family with GC policy to drop data that matches at least one condition.

// Define a GC rule to drop cells older than 5 days or not the most recent version
const unionRule = {
  rule: {
    versions: 1,
    age: {
      seconds: 60 * 60 * 24 * 5,
      nanos: 0,
    },
    union: true,
  },
};

[family] = await table.createFamily('cf3', unionRule);
console.log(`Created column family ${family.id}`);

PHP

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
use Google\Cloud\Bigtable\Admin\V2\GcRule\Union as GcRuleUnion;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Protobuf\Duration;

/**
 * Create a new column family with a union GC rule
 *
 * @param string $projectId The Google Cloud project ID
 * @param string $instanceId The ID of the Bigtable instance where the table resides
 * @param string $tableId The ID of the table in which the rule needs to be created
 */
function create_family_gc_union(
    string $projectId,
    string $instanceId,
    string $tableId
): void {
    $tableAdminClient = new BigtableTableAdminClient();

    $tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

    print('Creating column family cf3 with union GC rule...' . PHP_EOL);
    // Create a column family with GC policy to drop data that matches
    // at least one condition.
    // Define a GC rule to drop cells older than 5 days or not the
    // most recent version

    $columnFamily3 = new ColumnFamily();

    $ruleUnion = new GcRuleUnion();
    $ruleUnionArray = [
        (new GcRule())->setMaxNumVersions(2),
        (new GcRule())->setMaxAge((new Duration())->setSeconds(3600 * 24 * 5))
    ];
    $ruleUnion->setRules($ruleUnionArray);
    $union = new GcRule();
    $union->setUnion($ruleUnion);

    $columnFamily3->setGCRule($union);

    $columnModification = new Modification();
    $columnModification->setId('cf3');
    $columnModification->setCreate($columnFamily3);
    $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
        ->setName($tableName)
        ->setModifications([$columnModification]);
    $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);

    print('Created column family cf3 with Union GC rule.' . PHP_EOL);
}

Ruby

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

# Create a column family with GC policy to drop data that matches at least
# one condition
max_age_rule = Google::Cloud::Bigtable::GcRule.max_age 60 * 60 * 24 * 5
max_versions_rule = Google::Cloud::Bigtable::GcRule.max_versions 2
union_gc_rule = Google::Cloud::Bigtable::GcRule.union max_age_rule, max_versions_rule
column_families = table.column_families do |cfs|
  cfs.add "cf3", gc_rule: union_gc_rule
end
family = column_families["cf3"]

以下部分展示了如何创建具有嵌套式垃圾回收政策的列族。嵌套式垃圾回收政策同时包含联合式规则和交叉式规则。

控制台

如需为列族中的单元格设置嵌套式垃圾回收政策，请执行以下操作：

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击表所在行中的 修改。

5. 点击要修改的列族旁边的 打开。

6. 选择自定义政策。

7. 在文本区域中输入垃圾回收规则，为 maxage 和/或maxversions 设置值。可接受的存在时间单位包括 ms、s、m、h 和 d，代表毫秒、秒、分钟、小时和天。

   例如，要保留两个最新单元格，即使两个单元格都存在超过一分钟，或者保留 10 个最新单元格，只要这些单元格的存在时间少于一分钟，请输入以下内容：

   (maxage=1m and maxversions=2) or maxversions=10
   

8. 点击保存。

cbt

此示例会创建一个名为 cf5 的列族，然后设置一项垃圾回收政策以移除列族中满足以下任一条件的单元格：

• 早于 10 个最新单元格
• 存在时间超过一分钟，且晚于两个最新的单元格

换句话说，此政策可保留两个最新单元格，即使两个单元格都存在超过一分钟，或者保留 10 个最新单元格，只要这些单元格的存在时间少于一分钟。

cbt createfamily your-table cf5
cbt setgcpolicy your-table cf5 "(maxage=1m and maxversions=2) or
maxversions=10"

Go

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

import (
	"context"
	"fmt"
	"io"
	"time"

	"cloud.google.com/go/bigtable"
)

func createFamilyGCNested(w io.Writer, projectID, instanceID string, tableName string) error {
	// projectID := "my-project-id"
	// instanceID := "my-instance-id"
	// tableName := "my-table-name"

	ctx := context.Background()

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

	columnFamilyName := "cf5"
	if err := adminClient.CreateColumnFamily(ctx, tableName, columnFamilyName); err != nil {
		return fmt.Errorf("CreateColumnFamily(%s): %w", columnFamilyName, err)
	}

	// Create a nested GC rule:
	// Drop cells that are either older than the 10 recent versions
	// OR
	// Drop cells that are older than a month AND older than the 2 recent versions
	maxAge := time.Hour * 24 * 5
	maxAgePolicy := bigtable.MaxAgePolicy(maxAge)
	policy := bigtable.UnionPolicy(
		bigtable.MaxVersionsPolicy(10),
		bigtable.IntersectionPolicy(
			bigtable.MaxVersionsPolicy(2),
			maxAgePolicy))
	if err := adminClient.SetGCPolicy(ctx, tableName, columnFamilyName, policy); err != nil {
		return fmt.Errorf("SetGCPolicy(%s): %w", policy, err)
	}

	fmt.Fprintf(w, "created column family %s with policy: %v\n", columnFamilyName, policy)
	return nil
}

Java

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Creates a nested GC rule:
// Drop cells that are either older than the 10 recent versions
// OR
// Drop cells that are older than a month AND older than the 2 recent versions
VersionRule versionRule1 = GCRULES.maxVersions(10);
VersionRule versionRule2 = GCRULES.maxVersions(2);
DurationRule maxAgeRule = GCRULES.maxAge(30, TimeUnit.DAYS);
IntersectionRule intersectionRule = GCRULES.intersection().rule(maxAgeRule).rule(versionRule2);
UnionRule unionRule = GCRULES.union().rule(intersectionRule).rule(versionRule1);

// Creates column family with given GC rule.
try {
  // ModifyColumnFamiliesRequest can be used both for adding and modifying families, here it is
  // being used to add a family
  ModifyColumnFamiliesRequest columnFamiliesRequest =
      ModifyColumnFamiliesRequest.of(tableId).addFamily(COLUMN_FAMILY_5, unionRule);
  adminClient.modifyFamilies(columnFamiliesRequest);
  System.out.println("Created column family: " + COLUMN_FAMILY_5);
} catch (AlreadyExistsException e) {
  System.err.println(
      "Failed to create column family with rule, already exists: " + e.getMessage());
}

Python

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

    print("Creating column family cf5 with a Nested GC rule...")
    # Create a column family with nested GC policies.
    # Create a nested GC rule:
    # Drop cells that are either older than the 10 recent versions
    # OR
    # Drop cells that are older than a month AND older than the
    # 2 recent versions
    rule1 = column_family.MaxVersionsGCRule(10)
    rule2 = column_family.GCRuleIntersection(
        [
            column_family.MaxAgeGCRule(datetime.timedelta(days=30)),
            column_family.MaxVersionsGCRule(2),
        ]
    )

    nested_rule = column_family.GCRuleUnion([rule1, rule2])

    column_family5 = table.column_family("cf5", nested_rule)
    column_family5.create()
    print("Created column family cf5 with a Nested GC rule.")

C#

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a nested GC rule:
// Drop cells that are either older than the 10 recent versions
// OR
// Drop cells that are older than 5 days AND older than the 2 recent versions.
// Initialize request argument(s).
GcRule.Types.Intersection intersectionRule = new GcRule.Types.Intersection
{
    Rules =
    {
        new GcRule { MaxNumVersions = 2 },
        new GcRule { MaxAge = Duration.FromTimeSpan(TimeSpan.FromDays(5)) }
    }
};

GcRule.Types.Union nestedRule = new GcRule.Types.Union
{
    Rules =
    {
        new GcRule { MaxNumVersions = 10 },
        new GcRule { Intersection = intersectionRule }
    }
};

GcRule gcRule = new GcRule { Union = nestedRule };

// Column family to create
ColumnFamily columnFamily = new ColumnFamily { GcRule = gcRule };

TableName tableName = new TableName(projectId, instanceId, tableId);

// Modification to create column family
ModifyColumnFamiliesRequest.Types.Modification modification = new ModifyColumnFamiliesRequest.Types.Modification
{
    Create = columnFamily,
    Id = "cf5"
};

ModifyColumnFamiliesRequest request = new ModifyColumnFamiliesRequest
{
    TableName = tableName,
    Modifications = { modification }
};
try
{
    // Make the request
    Table response = bigtableTableAdminClient.ModifyColumnFamilies(request);
    Console.WriteLine("Created column family");
}
catch (Exception ex)
{
    Console.WriteLine($"Error creating column family {ex.Message}");
}

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;
namespace cbta = ::google::cloud::bigtable_admin;
using ::google::bigtable::admin::v2::ModifyColumnFamiliesRequest;
using ::google::cloud::StatusOr;
[](cbta::BigtableTableAdminClient admin, std::string const& project_id,
   std::string const& instance_id, std::string const& table_id,
   std::string const& family_name) {
  std::string table_name = cbt::TableName(project_id, instance_id, table_id);
  auto constexpr kSecondsPerDay =
      std::chrono::seconds(std::chrono::hours(24)).count();

  ModifyColumnFamiliesRequest::Modification mod;
  mod.set_id(family_name);
  auto& gc = *mod.mutable_create()->mutable_gc_rule();
  auto& gc_1 = *gc.mutable_union_()->add_rules();
  auto& gc_2 = *gc.mutable_union_()->add_rules();
  auto& gc_2_1 = *gc_2.mutable_intersection()->add_rules();
  auto& gc_2_2 = *gc_2.mutable_intersection()->add_rules();

  gc_1.set_max_num_versions(10);
  gc_2_1.set_max_num_versions(1);
  gc_2_2.mutable_max_age()->set_seconds(5 * kSecondsPerDay);

  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(table_name, {std::move(mod)});

  if (!schema) throw std::move(schema).status();
  std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}

Node.js

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Create a nested GC rule:
// Drop cells that are either older than the 10 recent versions
// OR
// Drop cells that are older than a month AND older than the 2 recent versions
const nestedRule = {
  union: true,
  versions: 10,
  rule: {
    versions: 2,
    age: {
      // one month
      seconds: 60 * 60 * 24 * 30,
      nanos: 0,
    },
  },
};

[family] = await table.createFamily('cf5', nestedRule);
console.log(`Created column family ${family.id}`);

PHP

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
use Google\Cloud\Bigtable\Admin\V2\GcRule\Intersection as GcRuleIntersection;
use Google\Cloud\Bigtable\Admin\V2\GcRule\Union as GcRuleUnion;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Protobuf\Duration;

/**
 * Create a new column family with a nested GC rule
 *
 * @param string $projectId The Google Cloud project ID
 * @param string $instanceId The ID of the Bigtable instance where the table resides
 * @param string $tableId The ID of the table in which the rule needs to be created
 */
function create_family_gc_nested(
    string $projectId,
    string $instanceId,
    string $tableId
): void {
    $tableAdminClient = new BigtableTableAdminClient();

    $tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);

    print('Creating column family cf5 with a Nested GC rule...' . PHP_EOL);
    // Create a column family with nested GC policies.
    // Create a nested GC rule:
    // Drop cells that are either older than the 10 recent versions
    // OR
    // Drop cells that are older than a month AND older than the
    // 2 recent versions
    $columnFamily5 = new ColumnFamily();
    $rule1 = (new GcRule())->setMaxNumVersions(10);

    $rule2Intersection = new GcRuleIntersection();
    $rule2Duration1 = new Duration();
    $rule2Duration1->setSeconds(3600 * 24 * 30);
    $rule2Array = [
        (new GcRule())->setMaxAge($rule2Duration1),
        (new GcRule())->setMaxNumVersions(2)
    ];
    $rule2Intersection->setRules($rule2Array);
    $rule2 = new GcRule();
    $rule2->setIntersection($rule2Intersection);

    $nestedRule = new GcRuleUnion();
    $nestedRule->setRules([
        $rule1,
        $rule2
    ]);
    $nestedRule = (new GcRule())->setUnion($nestedRule);

    $columnFamily5->setGCRule($nestedRule);

    $columnModification = new Modification();
    $columnModification->setId('cf5');
    $columnModification->setCreate($columnFamily5);
    $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
        ->setName($tableName)
        ->setModifications([$columnModification]);
    $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);

    print('Created column family cf5 with a Nested GC rule.' . PHP_EOL);
}

Ruby

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

# Create a nested GC rule:
# Drop cells that are either older than the 10 recent versions
# OR
# Drop cells that are older than a month AND older than the 2 recent versions
max_versions_rule1 = Google::Cloud::Bigtable::GcRule.max_versions 10
max_age_rule = Google::Cloud::Bigtable::GcRule.max_age 60 * 60 * 24 * 5
max_versions_rule2 = Google::Cloud::Bigtable::GcRule.max_versions 2
intersection_gc_rule = Google::Cloud::Bigtable::GcRule.intersection max_age_rule, max_versions_rule2
nested_gc_rule = Google::Cloud::Bigtable::GcRule.union max_versions_rule1, intersection_gc_rule

更新垃圾回收政策

以下示例演示了如何修改现有的垃圾回收政策。

要延长使用 您必须确认有关复制作业的 不同步。新值不得晚于当前值 90 天。有关详情，请参阅 更改基于年龄的政策。

控制台

如需更新列族的垃圾回收政策，请遵循以下 步骤。

注意 ：您无法使用控制台来增加 max age。使用 cbt CLI 。

1. 在 Google Cloud 控制台中打开 Bigtable 实例列表。

   打开实例列表

2. 点击要查看其表的实例。

3. 在左侧窗格中，点击表。

   “表”页面显示实例中的表列表。

4. 点击表所在行中的 修改。

5. 点击要修改的列族旁边的 打开。

6. 设置政策。

7. 点击保存。

cbt

cbt setgcpolicy your-table cf1 maxage=1d

如果要增加复制表中 maxage 的值，则必须使用 可选的 force 标志。新值不得晚于当前值 90 天。

Java

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Updates the column family metadata to update the GC rule.
// Updates a column family GC rule.
VersionRule versionRule = GCRULES.maxVersions(1);
try {
  // ModifyColumnFamiliesRequest can be used both for adding and modifying families, here it is
  // being used to modify a family
  // Updates column family with given GC rule.
  ModifyColumnFamiliesRequest updateRequest =
      ModifyColumnFamiliesRequest.of(tableId).updateFamily(COLUMN_FAMILY_1, versionRule);
  adminClient.modifyFamilies(updateRequest);
  System.out.printf("Column family %s GC rule updated%n", COLUMN_FAMILY_1);
} catch (NotFoundException e) {
  System.err.println("Failed to modify a non-existent column family: " + e.getMessage());
}

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。

print("Updating column family cf1 GC rule...")
# Update the column family cf1 to update the GC rule
column_family1 = table.column_family("cf1", column_family.MaxVersionsGCRule(1))
column_family1.update()
print("Updated column family cf1 GC rule\n")

C#

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Update the column family metadata to update the GC rule.
// Initialize request argument(s).
// Updated column family GC rule.
GcRule maxVersionsRule = new GcRule { MaxNumVersions = 1 };

// Column family to create
ColumnFamily columnFamily = new ColumnFamily { GcRule = maxVersionsRule };

TableName tableName = new TableName(projectId, instanceId, tableId);

// Modification to update column family
ModifyColumnFamiliesRequest.Types.Modification modification = new ModifyColumnFamiliesRequest.Types.Modification
{
    Update = columnFamily,
    Id = "cf1"
};

ModifyColumnFamiliesRequest request = new ModifyColumnFamiliesRequest
{
    TableName = tableName,
    Modifications = { modification }
};
try
{
    // Make the request
    Table response = bigtableTableAdminClient.ModifyColumnFamilies(request);
    Console.WriteLine("Updated column family");
}
catch (Exception ex)
{
    Console.WriteLine($"Error updating column family {ex.Message}");
}

C++

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

namespace cbt = ::google::cloud::bigtable;
namespace cbta = ::google::cloud::bigtable_admin;
using ::google::bigtable::admin::v2::ModifyColumnFamiliesRequest;
using ::google::cloud::StatusOr;
[](cbta::BigtableTableAdminClient admin, std::string const& project_id,
   std::string const& instance_id, std::string const& table_id,
   std::string const& family_name) {
  std::string table_name = cbt::TableName(project_id, instance_id, table_id);

  ModifyColumnFamiliesRequest::Modification mod;
  mod.set_id(family_name);
  mod.mutable_update()->mutable_gc_rule()->set_max_num_versions(1);

  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(table_name, {std::move(mod)});

  if (!schema) throw std::move(schema).status();
  std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}

Node.js

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

// Update the column family metadata to update the GC rule

// Create a reference to the column family
family = table.family('cf1');

// Update a column family GC rule
const updatedMetadata = {
  rule: {
    versions: 1,
  },
};

const [apiResponse] = await family.setMetadata(updatedMetadata);
console.log(`Updated GC rule: ${JSON.stringify(apiResponse)}`);

PHP

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

use Google\ApiCore\ApiException;
use Google\Cloud\Bigtable\Admin\V2\Client\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;

/**
 * Update the GC Rule for an existing column family in the table
 *
 * @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 where the rule needs to be updated
 * @param string $familyId The ID of the column family
 */
function update_gc_rule(
    string $projectId,
    string $instanceId,
    string $tableId,
    string $familyId = 'cf3'
): void {
    $tableAdminClient = new BigtableTableAdminClient();
    $tableName = $tableAdminClient->tableName($projectId, $instanceId, $tableId);
    $columnFamily1 = new ColumnFamily();

    printf('Updating column family %s GC rule...' . PHP_EOL, $familyId);
    $columnFamily1->setGcRule((new GcRule())->setMaxNumVersions(1));
    // Update the column family with ID $familyId to update the GC rule
    $columnModification = new Modification();
    $columnModification->setId($familyId);
    $columnModification->setUpdate($columnFamily1);

    try {
        $modifyColumnFamiliesRequest = (new ModifyColumnFamiliesRequest())
            ->setName($tableName)
            ->setModifications([$columnModification]);
        $tableAdminClient->modifyColumnFamilies($modifyColumnFamiliesRequest);
    } catch (ApiException $e) {
        if ($e->getStatus() === 'NOT_FOUND') {
            printf('Column family %s does not exist.' . PHP_EOL, $familyId);
            return;
        }
        throw $e;
    }

    printf('Print column family %s GC rule after update...' . PHP_EOL, $familyId);
    printf('Column Family: ' . $familyId . PHP_EOL);
    printf('%s' . PHP_EOL, $columnFamily1->serializeToJsonString());
}

Ruby

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

如需向 Bigtable 进行身份验证，请设置应用默认凭据。 如需了解详情，请参阅为客户端库设置身份验证。

gc_rule = Google::Cloud::Bigtable::GcRule.max_versions 1
column_families = table.column_families do |cfs|
  cfs.update "cf1", gc_rule: gc_rule
end
p column_families["cf1"]

后续步骤

• 查看其他代码示例。
• 探索模拟单元级 TTL 的策略。
• 了解时间戳为序列号对垃圾回收有何影响。
• 了解如何只保留列的最新值。