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MongoDB::command
Execute a database command
Description
public array MongoDB::command
( array $command
[, array $options = array()
] )
This method is identical to:
<?php
public function command($data) {
return $this->selectCollection('$cmd')->findOne($data);
}
?>
Parameters
-
command
-
The query to send.
-
options
-
This parameter is an associative array of the form
array("optionname" => <boolean>, ...). Currently
supported options are:
"timeout" Integer, defaults to MongoCursor::$timeout. If acknowledged writes are used, this sets how long (in milliseconds) for the client to wait for a database response. If the database does not respond within the timeout period, a MongoCursorTimeoutException will be thrown.
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 "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";
}
?>
The above example will output
something similar to:
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";
}
?>
The above example will output
something similar to:
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";
}
?>
The above example will output
something similar to:
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.
If you are going to be using MapReduce, Prajwal Tuladhar created an API for
Mongo PHP users which provides a nicer interface than the bare command. You
can download it from
» Github
and there is a
» blog post
on how to use it.
Example #4 MongoDB::command "textSearch" example
Do a fulltext search lookup with MongoDB's 2.4 and higher "text search"
functionality.
<?php
$m = new MongoClient();
$d = $m->demo;
$c = $d->planets;
$c->insert(array("name" => "Mercury", "desc" => "Mercury is the smallest and closest to the Sun"));
$c->insert(array("name" => "Venus", "desc" => "Venus is the second planet from the Sun, orbiting it every 224.7 Earth days."));
$c->insert(array("name" => "Earth", "desc" => "Earth is the the densest of the eight planets in the Solar System."));
$c->insert(array("name" => "Mars", "desc" => "Mars is named after the Roman god of war."));
$c->ensureIndex(array('desc' => 'text'));
$r = $d->command(array("text" => "planets", 'search' => "sun" ));
print_r($r);
?>
The above example will output
something similar to:
Array
(
[queryDebugString] => sun||||||
[language] => english
[results] => Array
(
[0] => Array
(
[score] => 0.625
[obj] => Array
(
[_id] => MongoId Object
(
[$id] => 517549d944670a4a5cb3059a
)
[name] => Mercury
[desc] => Mercury is the smallest and closest to the Sun
)
)
[1] => Array
(
[score] => 0.55
[obj] => Array
(
[_id] => MongoId Object
(
[$id] => 517549d944670a4a5cb3059b
)
[name] => Venus
[desc] => Venus is the second planet from the Sun, orbiting it every 224.7 Earth days.
)
)
)
[stats] => Array
(
[nscanned] => 2
[nscannedObjects] => 0
[n] => 2
[nfound] => 2
[timeMicros] => 95
)
[ok] => 1
)
Example #5 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);
?>
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