Consulta con el parámetro INT

Consulta datos mediante un parámetro INT.

Muestra de código

C++

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de Spanner.

Para autenticarte en Spanner, configura las credenciales predeterminadas de la aplicación. Si deseas obtener más información, consulta Configura la autenticación para un entorno de desarrollo local.

void QueryWithIntParameter(google::cloud::spanner::Client client) {
  namespace spanner = ::google::cloud::spanner;
  int example_int = 3000;
  spanner::SqlStatement select(
      "SELECT VenueId, VenueName, Capacity FROM Venues"
      " WHERE Capacity >= @capacity",
      {{"capacity", spanner::Value(example_int)}});
  using RowType = std::tuple<std::int64_t, absl::optional<std::string>,
                             absl::optional<std::int64_t>>;
  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 << "Capacity: " << std::get<2>(*row).value() << "\n";
  }
  std::cout << "Query completed for [spanner_query_with_int_parameter]\n";
}

C#

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de Spanner.


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

public class QueryWithIntAsyncSample
{
    public class Venue
    {
        public int VenueId { get; set; }
        public string VenueName { get; set; }
        public int Capacity { get; set; }
    }

    public async Task<List<Venue>> QueryWithIntAsync(string projectId, string instanceId, string databaseId)
    {
        string connectionString = $"Data Source=projects/{projectId}/instances/{instanceId}/databases/{databaseId}";
        // Initialize a long variable to use for querying.
        long exampleValue = 3000;

        using var connection = new SpannerConnection(connectionString);
        var cmd = connection.CreateSelectCommand("SELECT VenueId, VenueName, Capacity FROM Venues WHERE Capacity >= @ExampleValue");
        cmd.Parameters.Add("ExampleValue", SpannerDbType.Int64, exampleValue);

        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"),
                Capacity = reader.GetFieldValue<int>("Capacity")
            });
        }
        return venues;
    }
}

Go

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de Spanner.


import (
	"context"
	"fmt"
	"io"

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

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

	var exampleInt = 3000
	stmt := spanner.Statement{
		SQL: `SELECT VenueId, VenueName, Capacity FROM Venues
            	WHERE Capacity >= @capacity`,
		Params: map[string]interface{}{
			"capacity": exampleInt,
		},
	}
	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, capacity int64
		var venueName string
		if err := row.Columns(&venueID, &venueName, &capacity); err != nil {
			return err
		}
		fmt.Fprintf(w, "%d %s %d\n", venueID, venueName, capacity)
	}
}

Java

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de Spanner.

static void queryWithInt(DatabaseClient dbClient) {
  long exampleInt = 3000;
  Statement statement =
      Statement.newBuilder(
              "SELECT VenueId, VenueName, Capacity FROM Venues " + "WHERE Capacity >= @capacity")
          .bind("capacity")
          .to(exampleInt)
          .build();
  try (ResultSet resultSet = dbClient.singleUse().executeQuery(statement)) {
    while (resultSet.next()) {
      System.out.printf(
          "%d %s %d\n",
          resultSet.getLong("VenueId"),
          resultSet.getString("VenueName"),
          resultSet.getLong("Capacity"));
    }
  }
}

Node.js

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de 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: 'int64',
};

const exampleInt = 3000;

const query = {
  sql: `SELECT VenueId, VenueName, Capacity FROM Venues
          WHERE Capacity >= @capacity`,
  params: {
    capacity: exampleInt,
  },
  types: {
    capacity: 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},` +
        ` Capacity: ${json.Capacity}`
    );
  });
} catch (err) {
  console.error('ERROR:', err);
} finally {
  // Close the database when finished.
  database.close();
}

PHP

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de Spanner.

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

/**
 * Queries sample data from the database using SQL with a INT64 parameter.
 * Example:
 * ```
 * query_data_with_int_parameter($instanceId, $databaseId);
 * ```
 *
 * @param string $instanceId The Spanner instance ID.
 * @param string $databaseId The Spanner database ID.
 */
function query_data_with_int_parameter(string $instanceId, string $databaseId): void
{
    $spanner = new SpannerClient();
    $instance = $spanner->instance($instanceId);
    $database = $instance->database($databaseId);

    $exampleInt = 3000;

    $results = $database->execute(
        'SELECT VenueId, VenueName, Capacity FROM Venues ' .
        'WHERE Capacity >= @capacity',
        [
            'parameters' => [
                'capacity' => $exampleInt
            ]
        ]
    );

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

Python

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de 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)

exampleInt = 3000
param = {"capacity": exampleInt}
param_type = {"capacity": param_types.INT64}

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

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

Ruby

Para obtener información sobre cómo instalar y usar la biblioteca cliente de Spanner, consulta Bibliotecas cliente de 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, Capacity FROM Venues
             WHERE Capacity >= @capacity"

params      = { capacity: 3_000 }
param_types = { capacity: :INT64 }

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

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