关于分表的有关问题-PHP Tutorial-php.cn

Home

Backend Development

PHP Tutorial

关于分表的有关问题

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 13, 2016 pm 12:16 PM

100500idnbsp

关于分表的问题
我现在数据库中有三个表单数据都超过了500万数据,其中有个表超过1000千万,现在查询速度越来越慢

请教高手以下几个问题

1.将超过100万的表就进行分表.

2.如果B数据表拆分100万的表有十个,那么A表中的ID在B表有5条数据，保存在B数据表拆分的10个表中（问题出来了，在读取数据时，不可能去读去B表中所有的表，这5条数据可能放在拆分的第5与第6个表中，如果这样我们只里要读取B表的第5个表与第6个表就行了。前提是我们根本不知道数据在那）。
------解决思路----------------------
分表是有条件的，并非简单的按记录顺序切断
比如你的 A 和 B 是按 id 关联的，那么 B 就要按 A.id 拆分
这样在已知 A.id 的情况下，按拆分规则就可推算出相关的记录会出现在哪些 Bn 中

如果你的表间存在多对多的关系，那么分表就没有意义了
此时应使用过渡表保存关联关系，查询时要分两步走，而不是一次关联所有表
由于过渡表一般只有2列，虽然记录数很多，但一次性加载到内存的可能性很大（就算是需要多次加载，但每次可加载的记录数也很多）

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

PHP's Purpose: Building Dynamic WebsitesApr 15, 2025 am 12:18 AM

PHP is used to build dynamic websites, and its core functions include: 1. Generate dynamic content and generate web pages in real time by connecting with the database; 2. Process user interaction and form submissions, verify inputs and respond to operations; 3. Manage sessions and user authentication to provide a personalized experience; 4. Optimize performance and follow best practices to improve website efficiency and security.

PHP: Handling Databases and Server-Side LogicApr 15, 2025 am 12:15 AM

PHP uses MySQLi and PDO extensions to interact in database operations and server-side logic processing, and processes server-side logic through functions such as session management. 1) Use MySQLi or PDO to connect to the database and execute SQL queries. 2) Handle HTTP requests and user status through session management and other functions. 3) Use transactions to ensure the atomicity of database operations. 4) Prevent SQL injection, use exception handling and closing connections for debugging. 5) Optimize performance through indexing and cache, write highly readable code and perform error handling.

How do you prevent SQL Injection in PHP? (Prepared statements, PDO)Apr 15, 2025 am 12:15 AM

Using preprocessing statements and PDO in PHP can effectively prevent SQL injection attacks. 1) Use PDO to connect to the database and set the error mode. 2) Create preprocessing statements through the prepare method and pass data using placeholders and execute methods. 3) Process query results and ensure the security and performance of the code.

PHP and Python: Code Examples and ComparisonApr 15, 2025 am 12:07 AM

PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.

PHP in Action: Real-World Examples and ApplicationsApr 14, 2025 am 12:19 AM

PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.

PHP: Creating Interactive Web Content with EaseApr 14, 2025 am 12:15 AM

PHP makes it easy to create interactive web content. 1) Dynamically generate content by embedding HTML and display it in real time based on user input or database data. 2) Process form submission and generate dynamic output to ensure that htmlspecialchars is used to prevent XSS. 3) Use MySQL to create a user registration system, and use password_hash and preprocessing statements to enhance security. Mastering these techniques will improve the efficiency of web development.

PHP and Python: Comparing Two Popular Programming LanguagesApr 14, 2025 am 12:13 AM

PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.

The Enduring Relevance of PHP: Is It Still Alive?Apr 14, 2025 am 12:12 AM

PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers.

See all articles