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更新垃圾回收规则

更新列族垃圾回收规则。

深入探索

如需查看包含此代码示例的详细文档，请参阅以下内容：

配置垃圾回收

代码示例

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，请参阅为本地开发环境设置身份验证。

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";
}

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，请参阅为本地开发环境设置身份验证。

// 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}");
}

Go

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

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

import (
	"context"
	"fmt"
	"io"

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

func updateGCRule(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"
	// Update the column family cf1 to update the GC rule.
	policy := bigtable.MaxVersionsPolicy(1)
	if err := adminClient.SetGCPolicy(ctx, tableName, columnFamilyName, policy); err != nil {
		return fmt.Errorf("SetGCPolicy(%s): %w", policy, err)
	}

	fmt.Fprintf(w, "Updated column family %s GC rule 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，请参阅为本地开发环境设置身份验证。

// 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());
}

Node.js

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

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

// 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，请参阅为本地开发环境设置身份验证。

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());
}

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，请参阅为本地开发环境设置身份验证。

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")

Ruby

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

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

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

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