(PECL mongo >=0.9.0)
MongoDB::createCollection — Creates a collection
This method is used to create capped collections and other collections requiring special options. It is identical to running:
<?php
$collection = $db->command(array(
"create" => $name,
"capped" => $options["capped"],
"size" => $options["size"],
"max" => $options["max"],
"autoIndexId" => $options["autoIndexId"],
));
?>
name
The name of the collection.
options
An array containing options for the collections. Each option is its own element in the options array, with the option name listed below being the key of the element. The supported options depend on the MongoDB server version and storage engine, and the driver passes any option that you give it straight to the server. A few of the supported options are, but you can find a full list in the MongoDB core docs on » createCollection:
capped
If the collection should be a fixed size.
size
If the collection is fixed size, its size in bytes.
max
If the collection is fixed size, the maximum number of elements to store in the collection.
autoIndexId
If capped is TRUE you can specify FALSE to disable the
automatic index created on the _id field.
Before MongoDB 2.2, the default value for
autoIndexId was FALSE.
Returns a collection object representing the new collection.
Beispiel #1 MongoDB::createCollection() capped collection example
A capped collection is a special type of collection that has either a fixed or a fixed number of elements. Once the collection is "full," the oldest elements will be removed when new elements are added. Capped collections can be very useful for applications like logging, where you may want to reserve a certain amount of space for logs and not worry about them getting too big.
This example creates a very tiny log collection that will keep a maximum of 10 documents.
<?php
$log = $db->createCollection(
"logger",
array(
'capped' => true,
'size' => 10*1024,
'max' => 10
)
);
for ($i = 0; $i < 100; $i++) {
$log->insert(array("level" => WARN, "msg" => "sample log message #$i", "ts" => new MongoDate()));
}
$msgs = $log->find();
foreach ($msgs as $msg) {
echo $msg['msg']."\n";
}
?>
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
| Version | Beschreibung |
|---|---|
| 1.4.0 |
In versions before 1.4.0, the options were all arguments to the method. The function synopsis in those older versions is:
public MongoCollection MongoDB::createCollection
( string
$name
[, bool $capped = FALSE
[, int $size = 0
[, int $max = 0
]]] )
The meaning of the options is the same as described under the
|