Learning Notes MongoDB--Objectid composition Analysis

This paper mainly records how the MONGO auto-generated Objectid is formed.

Take a objectid as an example: 5996B6DE8E4F89047CEF0FEC

There are a total of 24 bits of 16 binary numbers, which is 12 bytes.

Where the first four bytes represent the current timestamp: 5996b6de

Then three bytes represents your host unique ID: 8e4f89

The following two bytes represent the process identifier (PID):047c

The last three bytes are a self-increasing random number: EF0FEC,

For example, a line range insert three data, the generated Objectid is: 5996bbc68e4f891e98d9485c,

5996BBC68E4F891E98D9485D,

5996bbc68e4f891e98d9485e

，

Learning Notes MongoDB--Objectid composition Analysis