这种情况mysql 如何建表比较好
条件:一个用户可以订阅多种邮件
需要的功能如下:
我查询一个用户 可以得出这个用户订阅的邮件种类
我查询一个邮件种类 可以得出哪些用户订阅了此邮件
这样子的话 如何建表比较合适
我的想法是建一个用户订阅表 和邮件表
用户订阅表中 一个字段 存 这个用户所有订阅的邮件ID
但是这样子有个问题
我查这个用户,可以方便知道这个用户订阅的种类
查一个邮件种类的话,查询哪些用户订阅了此邮件就比较麻烦了
大家有没有好的建表想法呢
------解决方案--------------------
可以建立3个表;
1个用户表;
一个邮件种类表;
在一个用户订阅邮件记录表;
这样操作起来和扩展起来都比较方便
------解决方案--------------------
三个表:
用户表、邮件表 和 用户订阅表
前两个你知道的
用户订阅表 有 用户id 和 邮件id 两个字段
从字段名就应该知道怎么做了
------解决方案--------------------
查询种类可以用模糊查询、正则或其他方法啊
不然如果有10万个种类(这不算大数目,新闻组比这还多)怎么办?

ThesecrettokeepingaPHP-poweredwebsiterunningsmoothlyunderheavyloadinvolvesseveralkeystrategies:1)ImplementopcodecachingwithOPcachetoreducescriptexecutiontime,2)UsedatabasequerycachingwithRedistolessendatabaseload,3)LeverageCDNslikeCloudflareforservin

You should care about DependencyInjection(DI) because it makes your code clearer and easier to maintain. 1) DI makes it more modular by decoupling classes, 2) improves the convenience of testing and code flexibility, 3) Use DI containers to manage complex dependencies, but pay attention to performance impact and circular dependencies, 4) The best practice is to rely on abstract interfaces to achieve loose coupling.

Yes,optimizingaPHPapplicationispossibleandessential.1)ImplementcachingusingAPCutoreducedatabaseload.2)Optimizedatabaseswithindexing,efficientqueries,andconnectionpooling.3)Enhancecodewithbuilt-infunctions,avoidingglobalvariables,andusingopcodecaching

ThekeystrategiestosignificantlyboostPHPapplicationperformanceare:1)UseopcodecachinglikeOPcachetoreduceexecutiontime,2)Optimizedatabaseinteractionswithpreparedstatementsandproperindexing,3)ConfigurewebserverslikeNginxwithPHP-FPMforbetterperformance,4)

APHPDependencyInjectionContainerisatoolthatmanagesclassdependencies,enhancingcodemodularity,testability,andmaintainability.Itactsasacentralhubforcreatingandinjectingdependencies,thusreducingtightcouplingandeasingunittesting.

Select DependencyInjection (DI) for large applications, ServiceLocator is suitable for small projects or prototypes. 1) DI improves the testability and modularity of the code through constructor injection. 2) ServiceLocator obtains services through center registration, which is convenient but may lead to an increase in code coupling.

PHPapplicationscanbeoptimizedforspeedandefficiencyby:1)enablingopcacheinphp.ini,2)usingpreparedstatementswithPDOfordatabasequeries,3)replacingloopswitharray_filterandarray_mapfordataprocessing,4)configuringNginxasareverseproxy,5)implementingcachingwi

PHPemailvalidationinvolvesthreesteps:1)Formatvalidationusingregularexpressionstochecktheemailformat;2)DNSvalidationtoensurethedomainhasavalidMXrecord;3)SMTPvalidation,themostthoroughmethod,whichchecksifthemailboxexistsbyconnectingtotheSMTPserver.Impl


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

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

Dreamweaver CS6
Visual web development tools

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft

WebStorm Mac version
Useful JavaScript development tools
