그래프에서 데이터 삭제

Spanner Graph에서 데이터를 삭제합니다.

코드 샘플

C++

Spanner용 클라이언트 라이브러리를 설치하고 사용하는 방법은 Spanner 클라이언트 라이브러리를 참조하세요.

Spanner에 인증하려면 애플리케이션 기본 사용자 인증 정보를 설정합니다. 자세한 내용은 로컬 개발 환경의 인증 설정을 참조하세요.

void DeleteData(google::cloud::spanner::Client client) {
  namespace spanner = ::google::cloud::spanner;

  // Delete the 'Owns' relationships with key (1,7) and (2,20).
  auto delete_ownerships =
      spanner::DeleteMutationBuilder("PersonOwnAccount",
                                     spanner::KeySet()
                                         .AddKey(spanner::MakeKey(1, 7))
                                         .AddKey(spanner::MakeKey(2, 20)))
          .Build();

  // Delete transfers using the keys in the range [1, 8]
  auto delete_transfer_range =
      spanner::DeleteMutationBuilder(
          "AccountTransferAccount",
          spanner::KeySet().AddRange(spanner::MakeKeyBoundClosed(1),
                                     spanner::MakeKeyBoundOpen(8)))
          .Build();

  // Deletes rows from the Account table and the AccountTransferAccount
  // table, because the AccountTransferAccount table is defined with
  // ON DELETE CASCADE.
  auto delete_accounts_all =
      spanner::MakeDeleteMutation("Account", spanner::KeySet::All());

  // Deletes rows from the Person table and the PersonOwnAccount table,
  // because the PersonOwnAccount table is defined with ON DELETE CASCADE.
  auto delete_persons_all =
      spanner::MakeDeleteMutation("Person", spanner::KeySet::All());

  auto commit_result = client.Commit(
      spanner::Mutations{delete_ownerships, delete_transfer_range,
                         delete_accounts_all, delete_persons_all});
  if (!commit_result) throw std::move(commit_result).status();
  std::cout << "Delete was successful [spanner_delete_graph_data]\n";
}

Go

Spanner용 클라이언트 라이브러리를 설치하고 사용하는 방법은 Spanner 클라이언트 라이브러리를 참조하세요.

Spanner에 인증하려면 애플리케이션 기본 사용자 인증 정보를 설정합니다. 자세한 내용은 로컬 개발 환경의 인증 설정을 참조하세요.

import (
	"context"
	"io"

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

func deleteGraphData(w io.Writer, db string) error {
	ctx := context.Background()
	client, err := spanner.NewClient(ctx, db)
	if err != nil {
		return err
	}
	defer client.Close()

	// Apply a series of mutations to tables underpinning edges and nodes in the
	// example graph. If there are referential integrity constraints defined
	// between edges and the nodes they connect, the edge must be deleted
	// before the nodes that the edge connects are deleted.
	m := []*spanner.Mutation{
		// spanner.Key can be used to delete a specific set of rows.
		// Delete the PersonOwnAccount rows with the key values (1,7) and (2,20).
		spanner.Delete("PersonOwnAccount", spanner.Key{1, 7}),
		spanner.Delete("PersonOwnAccount", spanner.Key{2, 20}),

		// spanner.KeyRange can be used to delete rows with a key in a specific range.
		// Delete a range of rows where the key prefix is >=1 and <8
		spanner.Delete("AccountTransferAccount",
			spanner.KeyRange{Start: spanner.Key{1}, End: spanner.Key{8}, Kind: spanner.ClosedOpen}),

		// spanner.AllKeys can be used to delete all the rows in a table.
		// Delete all Account rows, which will also delete the remaining
		// AccountTransferAccount rows since it was defined with ON DELETE CASCADE.
		spanner.Delete("Account", spanner.AllKeys()),

		// Delete remaining Person rows, which will also delete the remaining
		// PersonOwnAccount rows since it was defined with ON DELETE CASCADE.
		spanner.Delete("Person", spanner.AllKeys()),
	}
	_, err = client.Apply(ctx, m)
	return err
}

Java

Spanner용 클라이언트 라이브러리를 설치하고 사용하는 방법은 Spanner 클라이언트 라이브러리를 참조하세요.

Spanner에 인증하려면 애플리케이션 기본 사용자 인증 정보를 설정합니다. 자세한 내용은 로컬 개발 환경의 인증 설정을 참조하세요.

static void deleteData(DatabaseClient dbClient) {
  List<Mutation> mutations = new ArrayList<>();

  // KeySet.Builder can be used to delete a specific set of rows.
  // Delete the PersonOwnAccount rows with the key values (1,7) and (2,20).
  mutations.add(
      Mutation.delete(
          "PersonOwnAccount",
          KeySet.newBuilder().addKey(Key.of(1, 7)).addKey(Key.of(2, 20)).build()));

  // KeyRange can be used to delete rows with a key in a specific range.
  // Delete a range of rows where the key prefix is >=1 and <8
  mutations.add(
      Mutation.delete(
          "AccountTransferAccount", KeySet.range(KeyRange.closedOpen(Key.of(1), Key.of(8)))));

  // KeySet.all() can be used to delete all the rows in a table.
  // Delete all Account rows, which will also delete the remaining
  // AccountTransferAccount rows since it was defined with ON DELETE CASCADE.
  mutations.add(Mutation.delete("Account", KeySet.all()));

  // KeySet.all() can be used to delete all the rows in a table.
  // Delete all Person rows, which will also delete the remaining
  // PersonOwnAccount rows since it was defined with ON DELETE CASCADE.
  mutations.add(Mutation.delete("Person", KeySet.all()));

  dbClient.write(mutations);
  System.out.printf("Records deleted.\n");
}

Python

Spanner용 클라이언트 라이브러리를 설치하고 사용하는 방법은 Spanner 클라이언트 라이브러리를 참조하세요.

Spanner에 인증하려면 애플리케이션 기본 사용자 인증 정보를 설정합니다. 자세한 내용은 로컬 개발 환경의 인증 설정을 참조하세요.

def delete_data(instance_id, database_id):
    """Deletes sample data from the given database.

    The database, table, and data must already exist and can be created using
    `create_database` and `insert_data`.
    """
    spanner_client = spanner.Client()
    instance = spanner_client.instance(instance_id)
    database = instance.database(database_id)

    # Delete individual rows
    ownerships_to_delete = spanner.KeySet(keys=[[1, 7], [2, 20]])

    # Delete a range of rows where the column key is >=1 and <8
    transfers_range = spanner.KeyRange(start_closed=[1], end_open=[8])
    transfers_to_delete = spanner.KeySet(ranges=[transfers_range])

    # Delete Account/Person rows, which will also delete the remaining
    # AccountTransferAccount and PersonOwnAccount rows because
    # AccountTransferAccount and PersonOwnAccount are defined with
    # ON DELETE CASCADE
    remaining_nodes = spanner.KeySet(all_=True)

    with database.batch() as batch:
        batch.delete("PersonOwnAccount", ownerships_to_delete)
        batch.delete("AccountTransferAccount", transfers_to_delete)
        batch.delete("Account", remaining_nodes)
        batch.delete("Person", remaining_nodes)

    print("Deleted data.")

다음 단계

다른 Google Cloud 제품의 코드 샘플을 검색하고 필터링하려면 Google Cloud 샘플 브라우저를 참조하세요.