update : 2015.11.03
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Execute a database command
MongoDB
PHP Manual

MongoDB::command

(PECL mongo >=0.9.2)

MongoDB::command — Execute a database command

설명

public array MongoDB::command ( array $command [, array $options = array() [, string &$hash ]] )

Almost everything that is not a CRUD operation can be done with a database command. Need to know the database version? There's a command for that. Need to do aggregation? There's a command for that. Need to turn up logging? You get the idea.

This method is identical to:

<?php

public function command($data) {
    return $this->selectCollection('$cmd')->findOne($data);
}

?>

인수

command

The query to send.

options

An array of options for the index creation. Currently available options include:

  • "socketTimeoutMS"

    This option specifies the time limit, in milliseconds, for socket communication. If the server does not respond within the timeout period, a MongoCursorTimeoutException will be thrown and there will be no way to determine if the server actually handled the write or not. A value of -1 may be specified to block indefinitely. The default value for MongoClient is 30000 (30 seconds).

The following options are deprecated and should no longer be used:

  • "timeout"

    Deprecated alias for "socketTimeoutMS".

hash

Set to the connection hash of the server that executed the command. When the command result is suitable for creating a MongoCommandCursor, the hash is intended to be passed to MongoCommandCursor::createFromDocument().

The hash will also correspond to a connection returned from MongoClient::getConnections().

변경점

버전 설명
1.5.0

Renamed the "timeout" option to "socketTimeoutMS". Emits E_DEPRECATED when "timeout" is used.

Added hash by-reference parameter.

1.2.0 Added options parameter with a single option: "timeout".

반환값

Returns database response. Every database response is always maximum one document, which means that the result of a database command can never exceed 16MB. The resulting document's structure depends on the command, but most results will have the ok field to indicate success or failure and results containing an array of each of the resulting documents.

예제

Example #1 MongoDB::command() "distinct" example

Finding all of the distinct values for a key.

<?php

$people = $db->people;

$people->insert(array("name" => "Joe", "age" => 4));
$people->insert(array("name" => "Sally", "age" => 22));
$people->insert(array("name" => "Dave", "age" => 22));
$people->insert(array("name" => "Molly", "age" => 87));

$ages = $db->command(array("distinct" => "people", "key" => "age"));

foreach ($ages['values'] as $age) {
    echo "$age\n";
}

?>

위 예제의 출력 예시:


4
22
87

Example #2 MongoDB::command() "distinct" example

Finding all of the distinct values for a key, where the value is larger than or equal to 18.

<?php

$people = $db->people;

$people->insert(array("name" => "Joe", "age" => 4));
$people->insert(array("name" => "Sally", "age" => 22));
$people->insert(array("name" => "Dave", "age" => 22));
$people->insert(array("name" => "Molly", "age" => 87));

$ages = $db->command(
    array(
        "distinct" => "people",
        "key" => "age", 
        "query" => array("age" => array('$gte' => 18))
    )
);  

foreach ($ages['values'] as $age) {
    echo "$age\n";
}

?>

위 예제의 출력 예시:


22
87

Example #3 MongoDB::command() MapReduce example

Get all users with at least on "sale" event, and how many times each of these users has had a sale.

<?php

// sample event document
$events->insert(array("user_id" => $id, 
    "type" => $type, 
    "time" => new MongoDate(), 
    "desc" => $description));

// construct map and reduce functions
$map = new MongoCode("function() { emit(this.user_id,1); }");
$reduce = new MongoCode("function(k, vals) { ".
    "var sum = 0;".
    "for (var i in vals) {".
        "sum += vals[i];". 
    "}".
    "return sum; }");

$sales = $db->command(array(
    "mapreduce" => "events", 
    "map" => $map,
    "reduce" => $reduce,
    "query" => array("type" => "sale"),
    "out" => array("merge" => "eventCounts")));

$users = $db->selectCollection($sales['result'])->find();

foreach ($users as $user) {
    echo "{$user['_id']} had {$user['value']} sale(s).\n";
}

?>

위 예제의 출력 예시:


User 47cc67093475061e3d9536d2 had 3 sale(s).
User 49902cde5162504500b45c2c had 14 sale(s).
User 4af467e4fd543cce7b0ea8e2 had 1 sale(s).

Note: Using MongoCode

This example uses MongoCode, which can also take a scope argument. However, at the moment, MongoDB does not support using scopes in MapReduce. If you would like to use client-side variables in the MapReduce functions, you can add them to the global scope by using the optional scope field with the database command. See the » MapReduce documentation for more information.

Note: The out argument

Before 1.8.0, the out argument was optional. If you did not use it, MapReduce results would be written to a temporary collection, which would be deleted when your connection was closed. In 1.8.0+, the out argument is required. See the » MapReduce documentation for more information.

Example #4 MongoDB::command() "geoNear" example

This example shows how to use the geoNear command.

<?php
$m = new MongoClient();
$d = $m->demo;
$c = $d->poiConcat;

$r = $d->command(array(
    'geoNear' => "poiConcat",      // Search in the poiConcat collection
    'near' => array(-0.08, 51.48), // Search near 51.48°N, 0.08°E
    'spherical' => true,           // Enable spherical search
    'num' => 5,                    // Maximum 5 returned documents
));
print_r($r);
?>

참고

MongoDB core docs on » database commands and on individual commands: » findAndModify, » getLastError, and » repairDatabase (dozens more exist, there are merely a few examples).

MongoDB
PHP Manual