Stratégie de récupération de mémoire imbriquée

Crée une famille de colonnes avec une stratégie de récupération de mémoire imbriquée, si cette option est disponible.

Pages de documentation incluant cet exemple de code

Pour afficher l'exemple de code utilisé en contexte, consultez la documentation suivante :

Exemple de code

C#

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

// 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++

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

namespace cbt = ::google::cloud::bigtable;
using ::google::cloud::StatusOr;
[](cbt::TableAdmin admin, std::string const& table_id,
   std::string const& family_name) {
  StatusOr<google::bigtable::admin::v2::Table> schema =
      admin.ModifyColumnFamilies(
          table_id,
          {cbt::ColumnFamilyModification::Create(
              family_name,
              cbt::GcRule::Union(
                  cbt::GcRule::MaxNumVersions(10),
                  cbt::GcRule::Intersection(
                      cbt::GcRule::MaxNumVersions(1),
                      cbt::GcRule::MaxAge(5 * std::chrono::hours(24)))))});

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

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 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: %v", err)
	}
	defer adminClient.Close()

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

Node.js

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

// 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

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

use Google\Cloud\Bigtable\Admin\V2\GcRule\Intersection as GcRuleIntersection;
use Google\Cloud\Bigtable\Admin\V2\ModifyColumnFamiliesRequest\Modification;
use Google\Cloud\Bigtable\Admin\V2\GcRule\Union as GcRuleUnion;
use Google\Cloud\Bigtable\Admin\V2\BigtableTableAdminClient;
use Google\Cloud\Bigtable\Admin\V2\ColumnFamily;
use Google\Cloud\Bigtable\Admin\V2\GcRule;
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);
    $tableAdminClient->modifyColumnFamilies($tableName, [$columnModification]);

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

Python

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

    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.')

Ruby

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

# 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

Étape suivante

Pour rechercher et filtrer des exemples de code pour d'autres produits Google Cloud, consultez l'exemple de navigateur Google Cloud.