Create database with a property graph

Create a database using a property graph.

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For detailed documentation that includes this code sample, see the following:

• Set up and query Spanner Graph

Code sample

C++

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

To authenticate to Spanner, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

void CreateDatabaseWithPropertyGraph(
    google::cloud::spanner_admin::DatabaseAdminClient client,
    std::string const& project_id, std::string const& instance_id,
    std::string const& database_id) {
  google::cloud::spanner::Database database(project_id, instance_id,
                                            database_id);
  google::spanner::admin::database::v1::CreateDatabaseRequest request;
  request.set_parent(database.instance().FullName());
  request.set_create_statement("CREATE DATABASE `" + database.database_id() +
                               "`");
  request.add_extra_statements(R"""(
    CREATE TABLE Person (
      id               INT64 NOT NULL,
      name             STRING(MAX),
      birthday         TIMESTAMP,
      country          STRING(MAX),
      city             STRING(MAX),
    ) PRIMARY KEY (id))""");
  request.add_extra_statements(R"""(
    CREATE TABLE Account (
      id               INT64 NOT NULL,
      create_time      TIMESTAMP,
      is_blocked       BOOL,
      nick_name        STRING(MAX),
    ) PRIMARY KEY (id))""");
  request.add_extra_statements(R"""(
    CREATE TABLE PersonOwnAccount (
      id               INT64 NOT NULL,
      account_id       INT64 NOT NULL,
      create_time      TIMESTAMP,
      FOREIGN KEY (account_id)
      REFERENCES Account (id)
    ) PRIMARY KEY (id, account_id),
      INTERLEAVE IN PARENT Person ON DELETE CASCADE)""");
  request.add_extra_statements(R"""(
    CREATE TABLE AccountTransferAccount (
      id               INT64 NOT NULL,
      to_id            INT64 NOT NULL,
      amount           FLOAT64,
      create_time      TIMESTAMP NOT NULL,
      order_number     STRING(MAX),
      FOREIGN KEY (to_id) REFERENCES Account (id)
    ) PRIMARY KEY (id, to_id, create_time),
      INTERLEAVE IN PARENT Account ON DELETE CASCADE)""");
  request.add_extra_statements(R"""(
    CREATE OR REPLACE PROPERTY GRAPH FinGraph
      NODE TABLES (Account, Person)
      EDGE TABLES (
        PersonOwnAccount
          SOURCE KEY(id) REFERENCES Person(id)
          DESTINATION KEY(account_id) REFERENCES Account(id)
          LABEL Owns,
        AccountTransferAccount
          SOURCE KEY(id) REFERENCES Account(id)
          DESTINATION KEY(to_id) REFERENCES Account(id)
          LABEL Transfers))""");
  auto db = client.CreateDatabase(request).get();
  if (!db) throw std::move(db).status();
  std::cout << "Database " << db->name() << " created with property graph.\n";
}

Go

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

To authenticate to Spanner, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import (
	"context"
	"fmt"
	"io"
	"regexp"

	database "cloud.google.com/go/spanner/admin/database/apiv1"
	adminpb "google.golang.org/genproto/googleapis/spanner/admin/database/v1"
)

func createDatabaseWithPropertyGraph(ctx context.Context, w io.Writer, dbId string) error {
	// dbId is of the form:
	// 	projects/YOUR_PROJECT_ID/instances/YOUR_INSTANCE_ID/databases/YOUR_DATABASE_NAME
	matches := regexp.MustCompile("^(.*)/databases/(.*)$").FindStringSubmatch(dbId)
	if matches == nil || len(matches) != 3 {
		return fmt.Errorf("Invalid database id %s", dbId)
	}

	adminClient, err := database.NewDatabaseAdminClient(ctx)
	if err != nil {
		return err
	}
	defer adminClient.Close()

	var instance = matches[1]
	var dbName = matches[2]

	// The schema defintion for a database with a property graph comprises table
	// definitions one or more `CREATE PROPERTY GRAPH` statements to define the
	// property graph(s).
	//
	// Here, tables are created for 'Person's and 'Account's. The property graph
	// definition says that these entities form nodes in the graph. Similarly,
	// there are 'PersonOwnAccount' and 'AccountTransferAccount' relationship
	// tables defined. The property graph definition maps these to edges in the graph.
	var schema_statements = []string{
		`CREATE TABLE Person (
			id               INT64 NOT NULL,
			name             STRING(MAX),
			birthday         TIMESTAMP,
			country          STRING(MAX),
			city             STRING(MAX),
		) PRIMARY KEY (id)`,
		`CREATE TABLE Account (
			id               INT64 NOT NULL,
			create_time      TIMESTAMP,
			is_blocked       BOOL,
			nick_name        STRING(MAX),
		) PRIMARY KEY (id)`,
		`CREATE TABLE PersonOwnAccount (
			id               INT64 NOT NULL,
			account_id       INT64 NOT NULL,
			create_time      TIMESTAMP,
			FOREIGN KEY (account_id)
				REFERENCES Account (id)
		) PRIMARY KEY (id, account_id),
		INTERLEAVE IN PARENT Person ON DELETE CASCADE`,
		`CREATE TABLE AccountTransferAccount (
			id               INT64 NOT NULL,
			to_id            INT64 NOT NULL,
			amount           FLOAT64,
			create_time      TIMESTAMP NOT NULL,
			order_number     STRING(MAX),
			FOREIGN KEY (to_id) REFERENCES Account (id)
		) PRIMARY KEY (id, to_id, create_time),
		INTERLEAVE IN PARENT Account ON DELETE CASCADE`,
		`CREATE OR REPLACE PROPERTY GRAPH FinGraph
			NODE TABLES (Account, Person)
			EDGE TABLES (
				PersonOwnAccount
					SOURCE KEY(id) REFERENCES Person(id)
					DESTINATION KEY(account_id) REFERENCES Account(id)
					LABEL Owns,
				AccountTransferAccount
					SOURCE KEY(id) REFERENCES Account(id)
					DESTINATION KEY(to_id) REFERENCES Account(id)
					LABEL Transfers)`,
	}

	op, err := adminClient.CreateDatabase(ctx, &adminpb.CreateDatabaseRequest{
		Parent:          instance,
		CreateStatement: "CREATE DATABASE `" + dbName + "`",
		ExtraStatements: schema_statements,
	})
	if err != nil {
		return err
	}
	if _, err := op.Wait(ctx); err != nil {
		return err
	}
	fmt.Fprintf(w, "Created database [%s]\n", dbId)
	return nil
}

Java

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

To authenticate to Spanner, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

static void createDatabaseWithPropertyGraph(
    DatabaseAdminClient dbAdminClient, InstanceName instanceName, String databaseId) {
  CreateDatabaseRequest createDatabaseRequest =
      CreateDatabaseRequest.newBuilder()
          .setCreateStatement("CREATE DATABASE `" + databaseId + "`")
          .setParent(instanceName.toString())
          .addAllExtraStatements(
              Arrays.asList(
                  "CREATE TABLE Person ("
                      + "  id               INT64 NOT NULL,"
                      + "  name             STRING(MAX),"
                      + "  birthday         TIMESTAMP,"
                      + "  country          STRING(MAX),"
                      + "  city             STRING(MAX),"
                      + ") PRIMARY KEY (id)",
                  "CREATE TABLE Account ("
                      + "  id               INT64 NOT NULL,"
                      + "  create_time      TIMESTAMP,"
                      + "  is_blocked       BOOL,"
                      + "  nick_name        STRING(MAX),"
                      + ") PRIMARY KEY (id)",
                  "CREATE TABLE PersonOwnAccount ("
                      + "  id               INT64 NOT NULL,"
                      + "  account_id       INT64 NOT NULL,"
                      + "  create_time      TIMESTAMP,"
                      + "  FOREIGN KEY (account_id)"
                      + "  REFERENCES Account (id)"
                      + ") PRIMARY KEY (id, account_id),"
                      + "INTERLEAVE IN PARENT Person ON DELETE CASCADE",
                  "CREATE TABLE AccountTransferAccount ("
                      + "  id               INT64 NOT NULL,"
                      + "  to_id            INT64 NOT NULL,"
                      + "  amount           FLOAT64,"
                      + "  create_time      TIMESTAMP NOT NULL,"
                      + "  order_number     STRING(MAX),"
                      + "  FOREIGN KEY (to_id) REFERENCES Account (id)"
                      + ") PRIMARY KEY (id, to_id, create_time),"
                      + "INTERLEAVE IN PARENT Account ON DELETE CASCADE",
                  "CREATE OR REPLACE PROPERTY GRAPH FinGraph "
                      + "NODE TABLES (Account, Person)"
                      + "EDGE TABLES ("
                      + "  PersonOwnAccount"
                      + "    SOURCE KEY(id) REFERENCES Person(id)"
                      + "    DESTINATION KEY(account_id) REFERENCES Account(id)"
                      + "    LABEL Owns,"
                      + "  AccountTransferAccount"
                      + "    SOURCE KEY(id) REFERENCES Account(id)"
                      + "    DESTINATION KEY(to_id) REFERENCES Account(id)"
                      + "    LABEL Transfers)"))
          .build();
  try {
    // Initiate the request which returns an OperationFuture.
    com.google.spanner.admin.database.v1.Database db =
        dbAdminClient.createDatabaseAsync(createDatabaseRequest).get();
    System.out.println("Created database [" + db.getName() + "]");
  } catch (ExecutionException e) {
    // If the operation failed during execution, expose the cause.
    System.out.println("Encountered exception" + e.getCause());
    throw (SpannerException) e.getCause();
  } catch (InterruptedException e) {
    // Throw when a thread is waiting, sleeping, or otherwise occupied,
    // and the thread is interrupted, either before or during the activity.
    throw SpannerExceptionFactory.propagateInterrupt(e);
  }
}

Python

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

To authenticate to Spanner, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

def create_database_with_property_graph(instance_id, database_id):
    """Creates a database, tables and a property graph for sample data."""
    from google.cloud.spanner_admin_database_v1.types import spanner_database_admin

    spanner_client = spanner.Client()
    database_admin_api = spanner_client.database_admin_api

    request = spanner_database_admin.CreateDatabaseRequest(
        parent=database_admin_api.instance_path(spanner_client.project, instance_id),
        create_statement=f"CREATE DATABASE `{database_id}`",
        extra_statements=[
            """CREATE TABLE Person (
            id               INT64 NOT NULL,
            name             STRING(MAX),
            birthday         TIMESTAMP,
            country          STRING(MAX),
            city             STRING(MAX),
        ) PRIMARY KEY (id)""",
            """CREATE TABLE Account (
            id               INT64 NOT NULL,
            create_time      TIMESTAMP,
            is_blocked       BOOL,
            nick_name        STRING(MAX),
        ) PRIMARY KEY (id)""",
            """CREATE TABLE PersonOwnAccount (
            id               INT64 NOT NULL,
            account_id       INT64 NOT NULL,
            create_time      TIMESTAMP,
            FOREIGN KEY (account_id)
                REFERENCES Account (id)
        ) PRIMARY KEY (id, account_id),
        INTERLEAVE IN PARENT Person ON DELETE CASCADE""",
            """CREATE TABLE AccountTransferAccount (
            id               INT64 NOT NULL,
            to_id            INT64 NOT NULL,
            amount           FLOAT64,
            create_time      TIMESTAMP NOT NULL,
            order_number     STRING(MAX),
            FOREIGN KEY (to_id) REFERENCES Account (id)
        ) PRIMARY KEY (id, to_id, create_time),
        INTERLEAVE IN PARENT Account ON DELETE CASCADE""",
            """CREATE OR REPLACE PROPERTY GRAPH FinGraph
            NODE TABLES (Account, Person)
            EDGE TABLES (
                PersonOwnAccount
                    SOURCE KEY(id) REFERENCES Person(id)
                    DESTINATION KEY(account_id) REFERENCES Account(id)
                    LABEL Owns,
                AccountTransferAccount
                    SOURCE KEY(id) REFERENCES Account(id)
                    DESTINATION KEY(to_id) REFERENCES Account(id)
                    LABEL Transfers)""",
        ],
    )

    operation = database_admin_api.create_database(request=request)

    print("Waiting for operation to complete...")
    database = operation.result(OPERATION_TIMEOUT_SECONDS)

    print(
        "Created database {} on instance {}".format(
            database.name,
            database_admin_api.instance_path(spanner_client.project, instance_id),
        )
    )

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