Interroger les données à l'aide d'un paramètre DATE.
Exemple de code
C#
string connectionString =
$"Data Source=projects/{projectId}/instances/"
+ $"{instanceId}/databases/{databaseId}";
// Create a Date object to use for querying.
DateTime exampleDate = new DateTime(2019, 01, 01);
// Create connection to Cloud Spanner.
using (var connection = new SpannerConnection(connectionString))
{
var cmd = connection.CreateSelectCommand(
"SELECT VenueId, VenueName, LastContactDate FROM Venues "
+ "WHERE LastContactDate < @ExampleDate");
cmd.Parameters.Add("ExampleDate",
SpannerDbType.Date, exampleDate);
using (var reader = await cmd.ExecuteReaderAsync())
{
while (await reader.ReadAsync())
{
Console.WriteLine(
reader.GetFieldValue<string>("VenueId")
+ " " + reader.GetFieldValue<string>("VenueName")
+ " " + reader.
GetFieldValue<string>("LastContactDate"));
}
}
}
C++
void QueryWithDateParameter(google::cloud::spanner::Client client) {
namespace spanner = ::google::cloud::spanner;
absl::CivilDay example_date(2019, 1, 1);
spanner::SqlStatement select(
"SELECT VenueId, VenueName, LastContactDate FROM Venues"
" WHERE LastContactDate < @last_contact_date",
{{"last_contact_date", spanner::Value(example_date)}});
using RowType = std::tuple<std::int64_t, absl::optional<std::string>,
absl::optional<absl::CivilDay>>;
auto rows = client.ExecuteQuery(std::move(select));
for (auto const& row : spanner::StreamOf<RowType>(rows)) {
if (!row) throw std::runtime_error(row.status().message());
std::cout << "VenueId: " << std::get<0>(*row) << "\t";
std::cout << "VenueName: " << std::get<1>(*row).value() << "\t";
std::cout << "LastContactDate: " << std::get<2>(*row).value() << "\n";
}
std::cout << "Query completed for [spanner_query_with_date_parameter]\n";
}
Go
import (
"context"
"fmt"
"io"
"time"
"cloud.google.com/go/civil"
"cloud.google.com/go/spanner"
"google.golang.org/api/iterator"
)
func queryWithDate(w io.Writer, db string) error {
ctx := context.Background()
client, err := spanner.NewClient(ctx, db)
if err != nil {
return err
}
defer client.Close()
var exampleDate = civil.Date{Year: 2019, Month: time.January, Day: 1}
stmt := spanner.Statement{
SQL: `SELECT VenueId, VenueName, LastContactDate FROM Venues
WHERE LastContactDate < @lastContactDate`,
Params: map[string]interface{}{
"lastContactDate": exampleDate,
},
}
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 lastContactDate civil.Date
if err := row.Columns(&venueID, &venueName, &lastContactDate); err != nil {
return err
}
fmt.Fprintf(w, "%d %s %v\n", venueID, venueName, lastContactDate)
}
}
Java
static void queryWithDate(DatabaseClient dbClient) {
String exampleDate = "2019-01-01";
Statement statement =
Statement.newBuilder(
"SELECT VenueId, VenueName, LastContactDate FROM Venues "
+ "WHERE LastContactDate < @lastContactDate")
.bind("lastContactDate")
.to(exampleDate)
.build();
try (ResultSet resultSet = dbClient.singleUse().executeQuery(statement)) {
while (resultSet.next()) {
System.out.printf(
"%d %s %s\n",
resultSet.getLong("VenueId"),
resultSet.getString("VenueName"),
resultSet.getDate("LastContactDate"));
}
}
}
Node.js
// 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: 'date',
};
const exampleDate = '2019-01-01';
const query = {
sql: `SELECT VenueId, VenueName, LastContactDate FROM Venues
WHERE LastContactDate < @lastContactDate`,
params: {
lastContactDate: exampleDate,
},
types: {
lastContactDate: fieldType,
},
};
// Queries rows from the Venues table.
try {
const [rows] = await database.run(query);
rows.forEach(row => {
const date = row[2]['value'];
const json = row.toJSON();
console.log(
`VenueId: ${json.VenueId}, VenueName: ${json.VenueName},` +
` LastContactDate: ${JSON.stringify(date).substring(1, 11)}`
);
});
} catch (err) {
console.error('ERROR:', err);
} finally {
// Close the database when finished.
database.close();
}
PHP
use Google\Cloud\Spanner\SpannerClient;
use Google\Cloud\Spanner\Database;
/**
* Queries sample data from the database using SQL with a DATE parameter.
* Example:
* ```
* query_data_with_date_parameter($instanceId, $databaseId);
* ```
*
* @param string $instanceId The Spanner instance ID.
* @param string $databaseId The Spanner database ID.
*/
function query_data_with_date_parameter($instanceId, $databaseId)
{
$spanner = new SpannerClient();
$instance = $spanner->instance($instanceId);
$database = $instance->database($databaseId);
$exampleDate = '2019-01-01';
$results = $database->execute(
'SELECT VenueId, VenueName, LastContactDate FROM Venues ' .
'WHERE LastContactDate < @lastContactDate',
[
'parameters' => [
'lastContactDate' => $exampleDate
]
]
);
foreach ($results as $row) {
printf('VenueId: %s, VenueName: %s, LastContactDate: %s' . PHP_EOL,
$row['VenueId'], $row['VenueName'], $row['LastContactDate']);
}
}
Python
# 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)
exampleDate = "2019-01-01"
param = {"last_contact_date": exampleDate}
param_type = {"last_contact_date": param_types.DATE}
with database.snapshot() as snapshot:
results = snapshot.execute_sql(
"SELECT VenueId, VenueName, LastContactDate FROM Venues "
"WHERE LastContactDate < @last_contact_date",
params=param,
param_types=param_type,
)
for row in results:
print(u"VenueId: {}, VenueName: {}, LastContactDate: {}".format(*row))
Ruby
# 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, LastContactDate FROM Venues
WHERE LastContactDate < @last_contact_date"
params = { last_contact_date: "2019-01-01" }
param_types = { last_contact_date: :DATE }
client.execute(sql_query, params: params, types: param_types).rows.each do |row|
puts "#{row[:VenueId]} #{row[:VenueName]} #{row[:LastContactDate]}"
end