用mysql_insert_id函数的话,当错作流程是:A页面插入了一条,id=1,B页面插入了一条,id=2,A页面执行mysql_insert_id获取到的id是1还是2?
回复讨论(解决方案)
A页面当然是 1
A页面当然是 1
我可以理解为是返回`当前页面`的上一步执行的inser语句的id吗,w3school上说得不太清楚
如果不是1 ,就麻烦了,那么写所有的东西,都要操心并发的问题了。
可以对mysql服务器发送查询
mysql_query("select LAST_INSERT_ID()");如果是一万个页面呢?再如果是重要的事务性操作呢?查询数据库比较靠谱
A页面的mysql_insert_id返回是1
MySQL的mysql_insert_id是针对MySQL进程来进行的,对于服务器来说mysql_query都是一个原子操作,不是MAX(id),就算在大并发的情况下也不会出现不准确的情况。
可以看看MySQL的
mysql_insert_id是这么定义的
my_ulonglong STDCALL mysql_insert_id(MYSQL *mysql)
{
return mysql->;last_used_con->;insert_id;
}
MYSQL参数是个结构体,里面包括数据库链接和一些当前数据库链接的状态值,
其中在MYSQL结构体里面有insert_id,mysql_insert_id函数返回的就是结构体里面的找个值。
肯定是1,自己可以实际操作一下,就明白了

What’s still popular is the ease of use, flexibility and a strong ecosystem. 1) Ease of use and simple syntax make it the first choice for beginners. 2) Closely integrated with web development, excellent interaction with HTTP requests and database. 3) The huge ecosystem provides a wealth of tools and libraries. 4) Active community and open source nature adapts them to new needs and technology trends.

PHP and Python are both high-level programming languages that are widely used in web development, data processing and automation tasks. 1.PHP is often used to build dynamic websites and content management systems, while Python is often used to build web frameworks and data science. 2.PHP uses echo to output content, Python uses print. 3. Both support object-oriented programming, but the syntax and keywords are different. 4. PHP supports weak type conversion, while Python is more stringent. 5. PHP performance optimization includes using OPcache and asynchronous programming, while Python uses cProfile and asynchronous programming.

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.


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

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

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

SublimeText3 Chinese version
Chinese version, very easy to use

Dreamweaver Mac version
Visual web development tools

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