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Requête avec le paramètre BOOL

Interroger les données à l'aide d'un paramètre BOOL.

Exemple de code

C++

Pour savoir comment installer et utiliser la bibliothèque cliente pour Spanner, consultez la page Bibliothèques clientes Spanner.

Pour vous authentifier auprès de Spanner, configurez le service Identifiants par défaut de l'application. Pour en savoir plus, consultez Configurer l'authentification pour un environnement de développement local.

void QueryWithBoolParameter(google::cloud::spanner::Client client) {
  namespace spanner = ::google::cloud::spanner;
  bool example_bool = true;
  spanner::SqlStatement select(
      "SELECT VenueId, VenueName, OutdoorVenue FROM Venues"
      " WHERE OutdoorVenue = @outdoor_venue",
      {{"outdoor_venue", spanner::Value(example_bool)}});
  using RowType = std::tuple<std::int64_t, absl::optional<std::string>,
                             absl::optional<bool>>;
  auto rows = client.ExecuteQuery(std::move(select));
  for (auto& row : spanner::StreamOf<RowType>(rows)) {
    if (!row) throw std::move(row).status();
    std::cout << "VenueId: " << std::get<0>(*row) << "\t";
    std::cout << "VenueName: " << std::get<1>(*row).value() << "\t";
    std::cout << "OutdoorVenue: " << std::get<2>(*row).value() << "\n";
  }
  std::cout << "Query completed for [spanner_query_with_bool_parameter]\n";
}

C#

Pour savoir comment installer et utiliser la bibliothèque cliente pour Spanner, consultez la page Bibliothèques clientes Spanner.

Pour vous authentifier auprès de Spanner, configurez les identifiants par défaut de l'application. Pour en savoir plus, consultez Configurer l'authentification pour un environnement de développement local.


using Google.Cloud.Spanner.Data;
using System.Collections.Generic;
using System.Threading.Tasks;

public class QueryWithBoolAsyncSample
{
    public class Venue
    {
        public int VenueId { get; set; }
        public string VenueName { get; set; }
        public bool OutdoorVenue { get; set; }
    }

    public async Task<List<Venue>> QueryWithBoolAsync(string projectId, string instanceId, string databaseId)
    {
        string connectionString = $"Data Source=projects/{projectId}/instances/{instanceId}/databases/{databaseId}";
        bool exampleBool = true;

        using var connection = new SpannerConnection(connectionString);
        var cmd = connection.CreateSelectCommand(
            "SELECT VenueId, VenueName, OutdoorVenue FROM Venues "
            + "WHERE OutdoorVenue = @ExampleBool");
        cmd.Parameters.Add("ExampleBool", SpannerDbType.Bool, exampleBool);

        var venues = new List<Venue>();
        using var reader = await cmd.ExecuteReaderAsync();
        while (await reader.ReadAsync())
        {
            venues.Add(new Venue
            {
                VenueId = reader.GetFieldValue<int>("VenueId"),
                VenueName = reader.GetFieldValue<string>("VenueName"),
                OutdoorVenue = reader.GetFieldValue<bool>("OutdoorVenue")
            });
        }
        return venues;
    }
}

Go

Pour savoir comment installer et utiliser la bibliothèque cliente pour Spanner, consultez la page Bibliothèques clientes Spanner.


import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/spanner"
	"google.golang.org/api/iterator"
)

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

	var exampleBool = true
	stmt := spanner.Statement{
		SQL: `SELECT VenueId, VenueName, OutdoorVenue FROM Venues
            	WHERE OutdoorVenue = @outdoorVenue`,
		Params: map[string]interface{}{
			"outdoorVenue": exampleBool,
		},
	}
	iter := client.Single().Query(ctx, stmt)
	defer iter.Stop()
	for {
		row, err := iter.Next()
		if err == iterator.Done {
			return nil
		}
		if err != nil {
			return err
		}
		var venueID int64
		var venueName string
		var outdoorVenue bool
		if err := row.Columns(&venueID, &venueName, &outdoorVenue); err != nil {
			return err
		}
		fmt.Fprintf(w, "%d %s %t\n", venueID, venueName, outdoorVenue)
	}
}

Java

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

static void queryWithBool(DatabaseClient dbClient) {
  boolean exampleBool = true;
  Statement statement =
      Statement.newBuilder(
              "SELECT VenueId, VenueName, OutdoorVenue FROM Venues "
                  + "WHERE OutdoorVenue = @outdoorVenue")
          .bind("outdoorVenue")
          .to(exampleBool)
          .build();
  try (ResultSet resultSet = dbClient.singleUse().executeQuery(statement)) {
    while (resultSet.next()) {
      System.out.printf(
          "%d %s %b\n",
          resultSet.getLong("VenueId"),
          resultSet.getString("VenueName"),
          resultSet.getBoolean("OutdoorVenue"));
    }
  }
}

Node.js

Pour savoir comment installer et utiliser la bibliothèque cliente pour Spanner, consultez la page Bibliothèques clientes Spanner.

// Imports the Google Cloud client library.
const {Spanner} = require('@google-cloud/spanner');

/**
 * TODO(developer): Uncomment the following lines before running the sample.
 */
// const projectId = 'my-project-id';
// const instanceId = 'my-instance';
// const databaseId = 'my-database';

// Creates a client
const spanner = new Spanner({
  projectId: projectId,
});

// Gets a reference to a Cloud Spanner instance and database.
const instance = spanner.instance(instanceId);
const database = instance.database(databaseId);

const fieldType = {
  type: 'bool',
};

const exampleBool = true;

const query = {
  sql: `SELECT VenueId, VenueName, OutdoorVenue FROM Venues
          WHERE OutdoorVenue = @outdoorVenue`,
  params: {
    outdoorVenue: exampleBool,
  },
  types: {
    outdoorVenue: fieldType,
  },
};

// Queries rows from the Venues table.
try {
  const [rows] = await database.run(query);

  rows.forEach(row => {
    const json = row.toJSON();
    console.log(
      `VenueId: ${json.VenueId}, VenueName: ${json.VenueName},` +
        ` OutdoorVenue: ${json.OutdoorVenue}`
    );
  });
} catch (err) {
  console.error('ERROR:', err);
} finally {
  // Close the database when finished.
  database.close();
}

PHP

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

use Google\Cloud\Spanner\SpannerClient;
use Google\Cloud\Spanner\Database;

/**
 * Queries sample data from the database using SQL with a BOOL parameter.
 * Example:
 * ```
 * query_data_with_bool_parameter($instanceId, $databaseId);
 * ```
 *
 * @param string $instanceId The Spanner instance ID.
 * @param string $databaseId The Spanner database ID.
 */
function query_data_with_bool_parameter(string $instanceId, string $databaseId): void
{
    $spanner = new SpannerClient();
    $instance = $spanner->instance($instanceId);
    $database = $instance->database($databaseId);

    $exampleBool = true;

    $results = $database->execute(
        'SELECT VenueId, VenueName, OutdoorVenue FROM Venues ' .
        'WHERE OutdoorVenue = @outdoorVenue',
        [
            'parameters' => [
                'outdoorVenue' => $exampleBool
            ]
        ]
    );

    foreach ($results as $row) {
        printf('VenueId: %s, VenueName: %s, OutdoorVenue: %s' . PHP_EOL,
            $row['VenueId'], $row['VenueName'],
            $row['OutdoorVenue'] ? 'True' : 'False');
    }
}

Python

Pour savoir comment installer et utiliser la bibliothèque cliente pour Spanner, consultez la page Bibliothèques clientes Spanner.

# instance_id = "your-spanner-instance"
# database_id = "your-spanner-db-id"
spanner_client = spanner.Client()
instance = spanner_client.instance(instance_id)
database = instance.database(database_id)

exampleBool = True
param = {"outdoor_venue": exampleBool}
param_type = {"outdoor_venue": param_types.BOOL}

with database.snapshot() as snapshot:
    results = snapshot.execute_sql(
        "SELECT VenueId, VenueName, OutdoorVenue FROM Venues "
        "WHERE OutdoorVenue = @outdoor_venue",
        params=param,
        param_types=param_type,
    )

    for row in results:
        print("VenueId: {}, VenueName: {}, OutdoorVenue: {}".format(*row))

Ruby

Pour savoir comment installer et utiliser la bibliothèque cliente pour Spanner, consultez la page Bibliothèques clientes Spanner.

# project_id  = "Your Google Cloud project ID"
# instance_id = "Your Spanner instance ID"
# database_id = "Your Spanner database ID"

require "google/cloud/spanner"

spanner = Google::Cloud::Spanner.new project: project_id
client  = spanner.client instance_id, database_id

sql_query = "SELECT VenueId, VenueName, OutdoorVenue FROM Venues
             WHERE OutdoorVenue = @outdoor_venue"

params      = { outdoor_venue: true }
param_types = { outdoor_venue: :BOOL }

client.execute(sql_query, params: params, types: param_types).rows.each do |row|
  puts "#{row[:VenueId]} #{row[:VenueName]} #{row[:OutdoorVenue]}"
end

Étapes suivantes

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