MONGODB.COMMAND(3) 1 MONGODB.COMMAND(3)
MongoDB::command - Execute a database command
SYNOPSIS
public array MongoDB::command (array $command, [array $options = array()], [string &$hash])
DESCRIPTION
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);
}
?>
PARAMETERS
o $command
- The query to send.
o $options
- An array of options for the index creation. Currently available options include:
o "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:
o "timeout"Deprecated alias for "socketTimeoutMS".
o $hash
- Set to the connection hash of the server that executed the command. When the command result is suitable for creating a MongoCom-
mandCursor, the hash is intended to be passed to MongoCommandCursor.createFromDocument(3). The hash will also correspond to a
connection returned from MongoClient.getConnections(3).
CHANGELOG
+--------+---------------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------------------+
| 1.5.0 | |
| | |
| | Renamed the "timeout" option to "socketTime- |
| | outMS". Emits E_DEPRECATED when "timeout" is |
| | used. Added hash by-reference parameter. |
| | |
| 1.2.0 | |
| | |
| | Added options parameter with a single option: |
| | "timeout". |
| | |
+--------+---------------------------------------------------+
RETURN VALUES
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.
EXAMPLES
Example #1
MongoDB.command(3) "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
";
}
?>
The above example will output something similar to:
22 87
Example #2
MongoDB.command(3) "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
";
}
?>
The above example will output something similar to:
87
Example #3
MongoDB.command(3) 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).
";
}
?>
The above example will output something similar to:
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 informa-
tion.
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 col-
lection, 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(3) "geoNear" example
This example shows how to use the geoNear command.
<?php
$m = new MongoClient();
$d = $m->demo;
$c = $d->poiConcat;
$r = $d->command(array(
'geoNear' => "poiConcat", // Search in the poiConcat collection
'near' => array(-0.08, 51.48), // Search near 51.48oN, 0.08oE
'spherical' => true, // Enable spherical search
'num' => 5, // Maximum 5 returned documents
));
print_r($r);
?>
SEE ALSO
MongoCollection::aggregate, MongoCollection::findAndModify, MongoCollection::group.
MongoDB core docs on database commands and on individual commands: findAndModify, getLastError, and repairDatabase (dozens more exist,
there are merely a few examples).
PHP Documentation Group MONGODB.COMMAND(3)