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Stratégie de récupération de mémoire d'intersection

Crée une famille de colonnes avec une stratégie de récupération de mémoire d'intersection (âge et versions).

En savoir plus

Pour obtenir une documentation détaillée incluant cet exemple de code, consultez les pages suivantes :

Configurer la récupération de mémoire

Exemple de code

C++

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez la section Bibliothèques clientes Bigtable.

Pour vous authentifier auprès de Bigtable, configurez le service Identifiants par défaut de l'application. Pour en savoir plus, consultez Configurer l'authentification pour un environnement de développement local.

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";
}

C#

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez Bibliothèques clientes Bigtable.

Pour vous authentifier auprès de Bigtable, configurez les identifiants par défaut de l'application. Pour en savoir plus, consultez Configurer l'authentification pour un environnement de développement local.

// 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}");
}

Go

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez la section Bibliothèques clientes Bigtable.

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

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez la section Bibliothèques clientes Bigtable.

// 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());
}

Node.js

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez Bibliothèques clientes Bigtable.

// 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

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez la section Bibliothèques clientes Bigtable.

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);
}

Python

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez Bibliothèques clientes Bigtable.

    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.")

Ruby

Pour savoir comment installer et utiliser la bibliothèque cliente pour Bigtable, consultez la section Bibliothèques clientes Bigtable.

# 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"]

Étapes suivantes

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