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The MongoDB\BSON\ObjectId class

(mongodb >=1.0.0)

简介

BSON type for an » ObjectId. The value consists of 12 bytes, where the first four bytes are a timestamp that reflect the ObjectId's creation. Specifically, the value consists of:

a 4-byte value representing the seconds since the Unix epoch,
a 3-byte machine identifier,
a 2-byte process ID, and
a 3-byte counter, starting with a random value.

In MongoDB, each document stored in a collection requires a unique _id field that acts as a primary key. If an inserted document omits the _id field, the driver automatically generates an ObjectId for the _id field.

Using ObjectIds for the _id field provides the following additional benefits:

The creation time of the ObjectId may be accessed using the MongoDB\BSON\ObjectId::getTimestamp() method.
Sorting on an _id field that stores ObjectId values is roughly equivalent to sorting by creation time.

类摘要

final MongoDB\BSON\ObjectId implements MongoDB\BSON\ObjectIdInterface , MongoDB\BSON\Type , Serializable , JsonSerializable {

/* 方法 */

final public __construct ([ string $id ] )

final public getTimestamp ( void ) : int

final public jsonSerialize ( void ) : mixed

final public serialize ( void ) : string

final public __toString ( void ) : string

final public unserialize ( string $serialized ) : void

}

更新日志

版本	说明
1.3.0	Renamed from MongoDB\BSON\ObjectID to MongoDB\BSON\ObjectId.
1.2.0	Implements Serializable and JsonSerializable.

MongoDB\BSON\ObjectId::__construct — Construct a new ObjectId
MongoDB\BSON\ObjectId::getTimestamp — Returns the timestamp component of this ObjectId
MongoDB\BSON\ObjectId::jsonSerialize — Returns a representation that can be converted to JSON
MongoDB\BSON\ObjectId::serialize — Serialize an ObjectId
MongoDB\BSON\ObjectId::__toString — Returns the hexidecimal representation of this ObjectId
MongoDB\BSON\ObjectId::unserialize — Unserialize an ObjectId

User Contributed Notes

Mike T 25-May-2018 12:58


Worth noting this will throw an InvalidArgumentException if string is not in the correct format

naip1984 at gmail dot com 20-Dec-2017 01:44


I struggled for awhile to identify the way to find() using a ObjectID 



This seems to work, I hope this helps someone else out.  



$mongoId = '5a2493c33c95a1281836eb6a';



$collection->find(['_id'=> new MongoDB\BSON\ObjectId("$mongoId")]);



I found it here:   https://docs.mongodb.com/php-library/current/reference/method/MongoDBCollection-findOne/



Note this is for the PHP library, not the legacy library.

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The MongoDB\BSON\ObjectId class

简介

类摘要

更新日志

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User Contributed Notes

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