Update a garbage-collection rule

Update a column-family garbage-collection rule.

Documentation pages that include this code sample

To view the code sample used in context, see the following documentation:

Code sample

C#

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

// 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++

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

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::Update(
                        family_name, cbt::GcRule::MaxNumVersions(1))});

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

Go

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

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: %v", 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): %v", policy, err)
	}

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

Java

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

// 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

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

// 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

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

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

/**
 * 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 {
        $tableAdminClient->modifyColumnFamilies($tableName, [$columnModification]);
    } 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

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

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

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

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"]

What's next

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