MongoDB\Driver\Manager::executeCommand

(mongodb >=1.0.0)

MongoDB\Driver\Manager::executeCommand — Execute a database command

说明

final public MongoDB\Driver\Cursor MongoDB\Driver\Manager::executeCommand ( string $db , MongoDB\Driver\Command $command [, MongoDB\Driver\ReadPreference $readPreference ] )

Executes command on a server If readPreference is provided, it will be used for server selection; otherwise, the default read preference will be used.

参数

db (string)

The name of the database on which to execute the command.

command (MongoDB\Driver\Command)

The MongoDB\Driver\Command to execute.

readPreference (MongoDB\Driver\ReadPreference)

Optionally, a MongoDB\Driver\ReadPreference to select the server for this operation. If none is given, the read preference from the MongoDB Connection URI will be used.

返回值

Returns MongoDB\Driver\Cursor on success.

错误／异常

范例

Example #1 MongoDB\Driver\Manager::executeCommand() with a command returning a single result document

<?php

$manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
$command = new MongoDB\Driver\Command(['ping' => 1]);

try {
    $cursor = $manager->executeCommand('admin', $command);
} catch(MongoDB\Driver\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

/* The ping command returns a single result document, so we need to access the
 * first result in the cursor. */
$response = $cursor->toArray()[0];

var_dump($response);

?>

以上例程会输出：

array(1) {
  ["ok"]=>
  float(1)
}

Example #2 MongoDB\Driver\Manager::executeCommand() with a command returning a cursor

<?php

$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");

$bulk = new MongoDB\Driver\BulkWrite;
$bulk->insert(['x' => 1, 'y' => 'foo']);
$bulk->insert(['x' => 2, 'y' => 'bar']);
$bulk->insert(['x' => 3, 'y' => 'bar']);
$manager->executeBulkWrite('db.collection', $bulk);

$command = new MongoDB\Driver\Command([
    'aggregate' => 'collection',
    'pipeline' => [
        ['$group' => ['_id' => '$y', 'sum' => ['$sum' => '$x']]],
    ],
    'cursor' => new stdClass,
]);
$cursor = $manager->executeCommand('db', $command);

/* The aggregate command can optionally return its results in a cursor instead
 * of a single result document. In this case, we can iterate on the cursor
 * directly to access those results. */
foreach ($cursor as $document) {
    var_dump($document);
}

?>

以上例程会输出：

object(stdClass)#6 (2) {
  ["_id"]=>
  string(3) "bar"
  ["sum"]=>
  int(10)
}
object(stdClass)#7 (2) {
  ["_id"]=>
  string(3) "foo"
  ["sum"]=>
  int(2)
}

注释

Note:

This method does not take a MongoDB\Driver\WriteConcern parameter. For write commands (e.g. » findAndModify in MongoDB 3.2+), the write concern should be included in the command document itself.

If a secondary readPreference is used, it is the caller's responsibility to ensure that the command can be executed on a secondary. No validation is done by the driver.