创建具有交叉式垃圾回收政策（存在时间和版本）的列族。
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如需查看包含此代码示例的详细文档，请参阅以下内容：
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。
// 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 的客户端库，请参阅 Bigtable 客户端库。
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::runtime_error(schema.status().message());
std::cout << "Schema modified to: " << schema->DebugString() << "\n";
}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。
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: %v", err)
}
defer adminClient.Close()
columnFamilyName := "cf4"
if err := adminClient.CreateColumnFamily(ctx, tableName, columnFamilyName); err != nil {
return fmt.Errorf("CreateColumnFamily(%s): %v", 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): %v", 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。
// 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
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。
// 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 的客户端库，请参阅 Bigtable 客户端库。
use Google\Cloud\Bigtable\Admin\V2\GcRule\Intersection as GcRuleIntersection;
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\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);
$tableAdminClient->modifyColumnFamilies($tableName, [$columnModification]);
print('Created column family cf4 with Union GC rule' . PHP_EOL);
}
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。
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
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。
# 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"]后续步骤
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