MongoDB::commandExecute a database command
&reftitle.description;
publicarrayMongoDB::commandarraydata
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 running:
selectCollection('$cmd')->findOne($data);
?>
]]>
&reftitle.parameters;
data
The query to send.
&reftitle.returnvalues;
Returns database response.
&reftitle.examples;
<function>MongoDB::command</function> "distinct" example
Finding all of the distinct values for a key.
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";
}
?>
]]>
&example.outputs.similar;
4
22
87
<function>MongoDB::command</function> map/reduce example
Get all users with at least on "sale" event, and how many times each
of these users has had a sale.
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")));
$users = $db->selectCollection($sales['result'])->find();
foreach ($users as $user) {
echo "{$user['_id']} had {$user['value']} sale(s).\n";
}
?>
]]>
&example.outputs.similar;
User 47cc67093475061e3d9536d2 had 3 sale(s).
User 49902cde5162504500b45c2c had 14 sale(s).
User 4af467e4fd543cce7b0ea8e2 had 1 sale(s).
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.