mysql - 多用户同时请求一个PHP文件有可能得到相同的返回值吗?
如题,代码 如下 在多用户同时请求该文件时 会出现两个用户得到的返回值相同吗?
场景 该文是判断用户消耗的积分或者道具的数据 在数据表中相应 字段存储用户的积分或者道具数量,每次用户请求该文件 通过用户ID 进行查询用户的积分或者道具 之后进行对比 通过之后做其他操作
mysql_connect("localhost", "mysql_user", "mysql_password");
mysql_select_db("user");
$consume_props_count = 10;
$select = 'SELECT count
from user
where userid
=123456';
$query = mysql_query($select);
$row = mysql_fetch_assoc($query);
if ($row['count']
return false;
}
求大神赐教
PS 不太善于描述问题 望各位见谅.
回复内容:
如题,代码 如下 在多用户同时请求该文件时 会出现两个用户得到的返回值相同吗?
场景 该文是判断用户消耗的积分或者道具的数据 在数据表中相应 字段存储用户的积分或者道具数量,每次用户请求该文件 通过用户ID 进行查询用户的积分或者道具 之后进行对比 通过之后做其他操作
mysql_connect("localhost", "mysql_user", "mysql_password");
mysql_select_db("user");
$consume_props_count = 10;
$select = 'SELECT count
from user
where userid
=123456';
$query = mysql_query($select);
$row = mysql_fetch_assoc($query);
if ($row['count']
return false;
}
求大神赐教
PS 不太善于描述问题 望各位见谅.
假设其他程序不会修改代码中的变量或mysql中的数据,那么一定会返回相同值。
1、consume_props_count变量每次都是10且不做修改;
2、查询语句一样
所以一个用户请求多次或多个用户同时请求其结果都是一样的。
update
-------
还是无法从代码中看出什么。
你的返回值是false
或不返回,那么肯定会有一部分用户得到的是false
。
猜测你可能是想问多个请求同时到达会不会产生共享内存从而相互影响,PHP请求之间的资源是隔离开的,不同请求之间不能共享内存。请求间共享数据的方法就是从第三方读写数据(如MYSQL)。
没有数据修改的话肯定一样。
用户个人的数据是私有的,即便有修改也是用户自己这边引起的,有时序性,所以一般不会有问题,真多你的问题,建议你可以了解一下文件锁和mysql的事务隔离级别的知识。

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

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

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

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

Hot Topics



The future of PHP will be achieved by adapting to new technology trends and introducing innovative features: 1) Adapting to cloud computing, containerization and microservice architectures, supporting Docker and Kubernetes; 2) introducing JIT compilers and enumeration types to improve performance and data processing efficiency; 3) Continuously optimize performance and promote best practices.

PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries.

You can open phpMyAdmin through the following steps: 1. Log in to the website control panel; 2. Find and click the phpMyAdmin icon; 3. Enter MySQL credentials; 4. Click "Login".

MySQL and SQL are essential skills for developers. 1.MySQL is an open source relational database management system, and SQL is the standard language used to manage and operate databases. 2.MySQL supports multiple storage engines through efficient data storage and retrieval functions, and SQL completes complex data operations through simple statements. 3. Examples of usage include basic queries and advanced queries, such as filtering and sorting by condition. 4. Common errors include syntax errors and performance issues, which can be optimized by checking SQL statements and using EXPLAIN commands. 5. Performance optimization techniques include using indexes, avoiding full table scanning, optimizing JOIN operations and improving code readability.

MySQL is an open source relational database management system. 1) Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2) Basic operations: INSERT, UPDATE, DELETE and SELECT. 3) Advanced operations: JOIN, subquery and transaction processing. 4) Debugging skills: Check syntax, data type and permissions. 5) Optimization suggestions: Use indexes, avoid SELECT* and use transactions.

PHP is not dying, but constantly adapting and evolving. 1) PHP has undergone multiple version iterations since 1994 to adapt to new technology trends. 2) It is currently widely used in e-commerce, content management systems and other fields. 3) PHP8 introduces JIT compiler and other functions to improve performance and modernization. 4) Use OPcache and follow PSR-12 standards to optimize performance and code quality.

The methods for viewing SQL database errors are: 1. View error messages directly; 2. Use SHOW ERRORS and SHOW WARNINGS commands; 3. Access the error log; 4. Use error codes to find the cause of the error; 5. Check the database connection and query syntax; 6. Use debugging tools.

How to connect to MySQL using phpMyAdmin? The URL to access phpMyAdmin is usually http://localhost/phpmyadmin or http://[your server IP address]/phpmyadmin. Enter your MySQL username and password. Select the database you want to connect to. Click the "Connection" button to establish a connection.
