自学编程,想设计开发一个购物平台。商品只有一种,但是分为不同的类型,这个数据库该怎么设计呢?比方说书
书:
id: int
name: string
description: text
price: decimal
cover_image: string
书可以按照不同的条件来筛选,比方说按照分类,或者是按照书籍语言,发布时间,价格等等。。是设计一个category表
id: int
name: string
然后分别建立不同的category,然后让一本书归属于这些不同的category呢,还是把这些信息硬编码到书数据表中
id: int
name: string
description: text
language: string
type: string
price: decimal
正确的做法应该是怎样的呢?
回复内容:
自学编程,想设计开发一个购物平台。商品只有一种,但是分为不同的类型,这个数据库该怎么设计呢?比方说书
书:
id: int
name: string
description: text
price: decimal
cover_image: string
书可以按照不同的条件来筛选,比方说按照分类,或者是按照书籍语言,发布时间,价格等等。。是设计一个category表
id: int
name: string
然后分别建立不同的category,然后让一本书归属于这些不同的category呢,还是把这些信息硬编码到书数据表中
id: int
name: string
description: text
language: string
type: string
price: decimal
正确的做法应该是怎样的呢?
如图 ,请注意这只是一个可行的方案,并不是唯一解
(price单位建议用分,用int存储,避免浮点数精度问题)
语言,或者其它杂七杂八的属性你可以放到property属性表,然后具体书是否具有哪个属性在book_property里面加一行记录
分类因为展现比较频繁,所以单独列出,考虑一个关联表book_category的原因是不知道是否允许一本书出现在多个分类里面,如果一本书限死一个分类,那这个book_category可以省略,book表加一列category_id
另外,高阶的搜索和筛选功能你需要搜索引擎,Elastic Search, Sphinx, Xunsearch,Solr等等,你用MySQL一方面性能太差另一方面SQL太复杂,稍微深入之后你可以试着接入

Effective methods to prevent session fixed attacks include: 1. Regenerate the session ID after the user logs in; 2. Use a secure session ID generation algorithm; 3. Implement the session timeout mechanism; 4. Encrypt session data using HTTPS. These measures can ensure that the application is indestructible when facing session fixed attacks.

Implementing session-free authentication can be achieved by using JSONWebTokens (JWT), a token-based authentication system where all necessary information is stored in the token without server-side session storage. 1) Use JWT to generate and verify tokens, 2) Ensure that HTTPS is used to prevent tokens from being intercepted, 3) Securely store tokens on the client side, 4) Verify tokens on the server side to prevent tampering, 5) Implement token revocation mechanisms, such as using short-term access tokens and long-term refresh tokens.

The security risks of PHP sessions mainly include session hijacking, session fixation, session prediction and session poisoning. 1. Session hijacking can be prevented by using HTTPS and protecting cookies. 2. Session fixation can be avoided by regenerating the session ID before the user logs in. 3. Session prediction needs to ensure the randomness and unpredictability of session IDs. 4. Session poisoning can be prevented by verifying and filtering session data.

To destroy a PHP session, you need to start the session first, then clear the data and destroy the session file. 1. Use session_start() to start the session. 2. Use session_unset() to clear the session data. 3. Finally, use session_destroy() to destroy the session file to ensure data security and resource release.

How to change the default session saving path of PHP? It can be achieved through the following steps: use session_save_path('/var/www/sessions');session_start(); in PHP scripts to set the session saving path. Set session.save_path="/var/www/sessions" in the php.ini file to change the session saving path globally. Use Memcached or Redis to store session data, such as ini_set('session.save_handler','memcached'); ini_set(

TomodifydatainaPHPsession,startthesessionwithsession_start(),thenuse$_SESSIONtoset,modify,orremovevariables.1)Startthesession.2)Setormodifysessionvariablesusing$_SESSION.3)Removevariableswithunset().4)Clearallvariableswithsession_unset().5)Destroythe

Arrays can be stored in PHP sessions. 1. Start the session and use session_start(). 2. Create an array and store it in $_SESSION. 3. Retrieve the array through $_SESSION. 4. Optimize session data to improve performance.

PHP session garbage collection is triggered through a probability mechanism to clean up expired session data. 1) Set the trigger probability and session life cycle in the configuration file; 2) You can use cron tasks to optimize high-load applications; 3) You need to balance the garbage collection frequency and performance to avoid data loss.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 English version
Recommended: Win version, supports code prompts!

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

SublimeText3 Chinese version
Chinese version, very easy to use

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
