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MongoDB::command
(PECL mongo >=0.9.2)
MongoDB::command — Execute a database command
Beschreibung
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.
Parameter-Liste
- data
-
The query to send.
Rückgabewerte
Returns database response.
Beispiele
Beispiel #1 MongoDB::command() "distinct" example
Finding all of the distinct values for a key.
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$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";
}
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
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87
Beispiel #2 MongoDB::command() map/reduce example
Get all users with at least on "sale" event, and how many times each of these users has had a sale.
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// 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")));
$users = $db->selectCollection($sales['result'])->find();
foreach ($users as $user) {
echo "{$user['_id']} had {$user['value']} sale(s).\n";
}
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
User 47cc67093475061e3d9536d2 had 3 sale(s).
User 49902cde5162504500b45c2c had 14 sale(s).
User 4af467e4fd543cce7b0ea8e2 had 1 sale(s).