SELECT * FROM (SELECT a.video_name NAME,a.vid,a.pos,a.pic,a.definition,b.app_code,a.strength,a.ad_mark FROM access_app_video a
LEFT JOIN access_app b ON a.app_id=b.id WHERE tag_interest=2 AND app_id=1 AND a.ad_mark=1 AND a.status=0 ORDER BY ABS(tag_sex-16),ABS(tag_figure-10)) aa
ORDER BY aa.strength DESC LIMIT 0,12
该子查询如何改为连表查询
回复讨论(解决方案)
SELECT a.video_name NAME,a.vid,a.pos,a.pic,a.definition,b.app_code,a.strength,a.ad_mark FROM access_app_video a LEFT JOIN access_app b ON a.app_id=b.id WHERE tag_interest=2 AND app_id=1 AND a.ad_mark=1 AND a.status=0 ORDER BY a.strength, ABS(tag_sex-16),ABS(tag_figure-10) DESC LIMIT 0,12
感谢2楼回答,但是这样写,搜索出的结果和原结果是不同的,原sql的意思是先按照ABS(tag_sex-16),ABS(tag_figure-10)排序
之后再根据a.strength排序,2楼给的sql改变了排序规则。。
#2
该语句是不是不能使用连表查询?
最终的结果是按 a.strength 降序,当 a.strength 相同时 按 ABS(tag_sex-16),ABS(tag_figure-10) 升序
当然,当 ABS(tag_sex-16),ABS(tag_figure-10) 有多组相同值的时候,结果会略有不同
这也就是作者那样写的原因吧
5
是这样的,现在是想用orm去写sql,一直以为所有子查询都能用连表查询替代,才想把子查询改成连表查询,想了想,连表查询好像解决不了,只能继续这样写了

DependencyInjection(DI)inPHPenhancescodeflexibilityandtestabilitybydecouplingdependencycreationfromusage.ToimplementDIeffectively:1)UseDIcontainersjudiciouslytoavoidover-engineering.2)Avoidconstructoroverloadbylimitingdependenciestothreeorfour.3)Adhe

ToimproveyourPHPwebsite'sperformance,usethesestrategies:1)ImplementopcodecachingwithOPcachetospeedupscriptinterpretation.2)Optimizedatabasequeriesbyselectingonlynecessaryfields.3)UsecachingsystemslikeRedisorMemcachedtoreducedatabaseload.4)Applyasynch

Yes,itispossibletosendmassemailswithPHP.1)UselibrarieslikePHPMailerorSwiftMailerforefficientemailsending.2)Implementdelaysbetweenemailstoavoidspamflags.3)Personalizeemailsusingdynamiccontenttoimproveengagement.4)UsequeuesystemslikeRabbitMQorRedisforb

DependencyInjection(DI)inPHPisadesignpatternthatachievesInversionofControl(IoC)byallowingdependenciestobeinjectedintoclasses,enhancingmodularity,testability,andflexibility.DIdecouplesclassesfromspecificimplementations,makingcodemoremanageableandadapt

The best ways to send emails using PHP include: 1. Use PHP's mail() function to basic sending; 2. Use PHPMailer library to send more complex HTML mail; 3. Use transactional mail services such as SendGrid to improve reliability and analysis capabilities. With these methods, you can ensure that emails not only reach the inbox, but also attract recipients.

Calculating the total number of elements in a PHP multidimensional array can be done using recursive or iterative methods. 1. The recursive method counts by traversing the array and recursively processing nested arrays. 2. The iterative method uses the stack to simulate recursion to avoid depth problems. 3. The array_walk_recursive function can also be implemented, but it requires manual counting.

In PHP, the characteristic of a do-while loop is to ensure that the loop body is executed at least once, and then decide whether to continue the loop based on the conditions. 1) It executes the loop body before conditional checking, suitable for scenarios where operations need to be performed at least once, such as user input verification and menu systems. 2) However, the syntax of the do-while loop can cause confusion among newbies and may add unnecessary performance overhead.

Efficient hashing strings in PHP can use the following methods: 1. Use the md5 function for fast hashing, but is not suitable for password storage. 2. Use the sha256 function to improve security. 3. Use the password_hash function to process passwords to provide the highest security and convenience.


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

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

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

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Notepad++7.3.1
Easy-to-use and free code editor

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
