short unique id

Source: As long as the microcontroller has a true unique ID, you can make encryption indestructibleHttp://www.amobbs.com/thread-5518980-1-1.htmlFirst ring:ID-->F1 (ID)---"IDX,The ID is converted to an integer idx by a custom algorithm F1, F1 is an

In the development process, we usually use auto-increment numbers as the id primary key for data tables, and id is a numeric type, which is not easy to understand. After converting IDs into numbers in a certain format, it is easy to know what the

GUID: The globally unique Identifier (globally unique identifier) is also known as the UUID (universally unique Identifier). A GUID is a 128-bit numeric identifier produced by a particular algorithm that indicates the uniqueness of the product.

Typically a database can generate a unique ID, most of which is a sequence of numbers, or a combination of sequences like MongoDB, but this form of ID is predictable because it is a sequence. If you want an unpredictable and unique ID, there are

In the development process, our data table generally uses the self-increment number as the ID primary key, but the ID is the numeral type, is not easy to understand. After we have converted the IDs to numbers in a certain format, it is easy to know

根据用户id生成与之对应的唯一邀请码，范围为‘0-9A-Z’。The focus of this demand is the bold part, that is, to be able to reverse the introduction of the user ID according to the invitation code, so that the invitation code will not be put into storage, in the case of a

This article will introduce the differences between unique and primary constraints in mysql. unique and primary are the types we often use when creating mysql. Next I will introduce them to you. Fields defining the UNIQUE constraint cannot contain

This article focuses on the knowledge that PHP creates a unique numbering class based on the self-increment ID. Has a good reference value. Let's take a look at the little series. In the development process, our data table generally uses the

Android Address Book Management 3 short message acquisition and Sending Short Messages The first two blogs respectively talked about how to obtain contacts and call records. This topic describes how to get short messages. Short Messages are a

Question 1: What are the differences between mysql index types normal, unique, and fulltext? Normal: Indicates normal index unique: Indicates unique and duplicate indexes are not allowed. If the field information is not repeated, for example, when