ObjectId¶

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Description
Methods and Attributes
Examples

Description¶

ObjectId(<hexadecimal>)¶

Returns a new ObjectId value. The 12-byte ObjectId value consists of:

a 4-byte timestamp value, representing the ObjectId’s creation, measured in seconds since the Unix epoch
a 5-byte random value
a 3-byte incrementing counter, initialized to a random value

While the BSON format itself is little-endian, the timestamp and counter values are big-endian, with the most significant bytes appearing first in the byte sequence.

ObjectId() can accept the following parameter:

Field	Type	Description
`hexadecimal`	String	Optional. Hexadecimal string value for the new ObjectId.

Methods and Attributes¶

ObjectId() has the following attribute and methods:

Attribute/Method	Description
`str`	Returns the hexadecimal string representation of the object.
`ObjectId.getTimestamp()`	Returns the timestamp portion of the object as a Date.
`ObjectId.toString()`	Returns the JavaScript representation in the form of a string literal “`ObjectId(...)`”.
`ObjectId.valueOf()`	Returns the representation of the object as a hexadecimal string. The returned string is the `str` attribute.

Examples¶

Generate a New ObjectId¶

To generate a new ObjectId, use ObjectId() with no argument:

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x = ObjectId()

In this example, the value of x would be:

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ObjectId("507f1f77bcf86cd799439011")

Specify a Hexadecimal String¶

To generate a new ObjectId using ObjectId() with a unique hexadecimal string:

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y = ObjectId("507f191e810c19729de860ea")

In this example, the value of y would be:

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ObjectId("507f191e810c19729de860ea")

Access the Hexadecimal String¶

Access the str attribute of an ObjectId() object, as follows:

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ObjectId("507f191e810c19729de860ea").str

This operation will return the following hexadecimal string:

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507f191e810c19729de860ea