gst是什么| 狗哭了代表什么预兆| 元五行属什么| 969368是什么电话| 灵芝有什么作用与功效| 什么叫混合斑块| 什么护肤品| 骨质密度增高是什么意思| 强迫是什么意思| 什么掌不能拍| 大拇指指甲凹凸不平是什么原因| 长痔疮是什么引起的| 上环是什么意思| 静脉曲张是什么| 手术后吃什么鱼伤口愈合快| 望尘莫及什么意思| 低压高吃点什么药| 什么的东西| 六月初九是什么日子| 女人左眼跳是什么意思| 尿潴留是什么原因引起的| 尿多是什么原因| 亟待解决什么意思| dcr是什么| 白细胞低吃什么好| 吃黄体酮有什么副作用| 老子为什么叫老子| 豆包是什么| 急性支气管炎吃什么药| 专业术语是什么意思| pd是什么元素| 信手拈来是什么意思| 商量是什么意思| 特仑苏是什么意思| 麦芯粉是什么面粉| 经常头痛什么原因| 牡丹鹦鹉吃什么| 膈肌痉挛是什么症状| 女生肚脐眼下面疼是什么原因| 右上眼皮跳是什么预兆| 什么是富贵包| 收孕妇尿是干什么用的| 情何以堪是什么意思| 羊肉和什么菜包饺子好吃| 绿豆跟什么一起煮最好| 什么动物没有天敌| 变化无常的意思是什么| 重返20岁韩国版叫什么| 安全感是什么意思| 单核细胞偏高是什么原因| 金多水浊什么意思| bdsm是什么意思| 什么药消肿最快最有效| 白天嗜睡是什么原因| 产妇可以吃什么水果| 东莞有什么厂| 口臭看什么科| 脚气用什么| 脚底有痣代表什么意思| 什么的搏斗| 血压下午高是什么原因| 玉五行属什么| 带鱼为什么是扁的| 花生属于什么类食物| 怀孕初期分泌物是什么样的| 甘油是什么东西| 10月12是什么星座| 乘风破浪是什么意思| 哈伦裤配什么上衣好看| 暖五行属什么| 银杏叶子像什么| 甲状腺1类是什么意思| 月经和怀孕的症状有什么不同| 孙悟空的真名叫什么| 突然抽搐是什么原因| 摩羯座喜欢什么样的女生| 我能说什么| 脚指麻木是什么病先兆| 无纺布是什么| 鼠的五行属什么| 异常心电图是什么意思| 背后长痘痘什么原因| 隔空打牛是什么意思| 去医院看舌头挂什么科| 肺气肿挂什么科| o型阴性血是什么意思| 刘亦菲原名叫什么| 当我们谈论爱情时我们在谈论什么| 大牛是什么意思| 贤惠是什么意思| 一饿就胃疼是什么原因| 晚上1点是什么时辰| 补钙吃什么| 汉卿是什么意思| 呆呆的笑是什么笑| 婚姻是爱情的坟墓是什么意思| 一喝牛奶就拉肚子是什么原因| 肝郁脾虚吃什么药效果最好| 成双成对是什么数字| 敷设是什么意思| 胃窦黄斑瘤是什么病| 高我是什么意思| 为什么会肌酐高| 唐僧叫什么名字| 准备的近义词是什么| 胆怯的什么| 苦瓜炒什么好吃| 卡鱼刺去医院挂什么科| 韶字五行属什么| 贝塔是什么意思| 低密度灶是什么意思| 基质是什么| 贪嗔痴是什么意思| 月经周期是什么意思| 小便憋不住尿裤子是什么情况| 谷草谷丙高是什么原因| 狮子被称为什么| 卵巢炎症有什么症状| 二甲苯是什么东西| 喝什么茶最减肥| 衣服为什么会发霉| 2004年出生属什么| 心肌缺血吃什么药管用| 嗓子疼吃什么食物好| 坐月子吃什么水果好| 宫颈管短有什么症状| 三叉神经吃什么药好| 做ct挂什么科| 查脂肪肝挂什么科室| 热射病是什么原因引起的| 小麦淀粉是什么| 晚上睡觉放屁多是什么原因| 排毒吃什么最好能排脸上毒| 武装部部长是什么级别| 益生菌有什么作用| 病毒由什么组成| 法务是干什么的| 做梦下大雨是什么兆头| 脚上有水泡是什么原因| 仓鼠突然死了是为什么| 青绿色是什么颜色| 酉什么意思| 蜘蛛喜欢吃什么| 改进什么| 6.28什么星座| 梦到生儿子有什么预兆| 农历7月25日是什么星座| 真菌是什么| 让心归零是什么意思| 胃烧吃什么药| abo是什么意思| 为什么不建议吃大豆油| 鼻尖痒是什么原因| 为什么总是长口腔溃疡| 不动产是什么意思| 八月十一号是什么星座| 尿隐血2十是什么原因| 92年出生属什么生肖| 天贝是什么东西| 腾蛇是什么意思| 中国现在是什么社会| 喝什么茶最减肥| 肝脏低密度影是什么意思| 安琪儿是什么意思| 淡是什么意思| 充电宝100wh是什么意思| 鱼腥草有什么作用| 胃疼胃胀吃什么药好| 什么叫私生饭| 元辰是什么意思| 中国最贵的烟是什么烟| 肚脐眼左边是什么部位| 大驿土命是什么意思| 生肖羊生什么生肖最好| 胚胎停育有什么症状| 有黄鼻涕吃什么药| 杏花是什么生肖| 麦冬是什么植物| 全麻是什么感觉| 吃了避孕药后几天出血是什么原因| 信天翁是什么鸟| 闹乌龙是什么意思| 深夜里买醉是什么歌| 物欲横流是什么意思| 野蛮生长是什么意思| 早泄阳痿吃什么药| 一代明君功千秋是什么生肖| 犬和狗有什么区别| 第二性征是什么意思| 白头发吃什么可以改善| 减肥有什么方法| 上大便出血是什么原因| 什么食物补钙效果最好最快| 我流是什么意思| 小鬼是什么意思| 核苷酸是什么| 主任医师是什么职称| 耳加贵念什么| 乳酸脱氢酶偏低是什么意思| 七六年属什么| 泌尿是什么意思| 春宵一刻值千金什么意思| 55年出生属什么| 创字五行属什么| 什么是反流性食管炎| 睡觉趴着睡什么原因| 柏拉图爱情是什么意思| omega3是什么| 什么叫偏光眼镜| apl是什么意思| 胎神什么意思| 副歌部分是什么意思| ra是什么意思| 刺史相当于现在的什么官| 白眼球有红血丝是什么原因| 广州为什么叫羊城| 从良是什么意思| 为什么客厅不能放假花| 入港是什么意思| 户籍所在地是什么| 什么水果解酒| 胃痛胃胀吃什么药| 胆囊炎吃什么水果好| 三点水真读什么| 婴儿睡觉头上出汗多是什么原因| 乙肝核心抗体偏高是什么意思| 榴莲对孕妇有什么好处| 胸腺肿瘤是什么病| 张若昀原名叫什么| 画面感是什么意思| 市委讲师团是什么级别| 中国国菜是什么菜| 血糖高吃什么食物| 胃出血是什么症状| 屈光和近视有什么区别| 尿液泡沫多是什么原因| 马失前蹄下一句是什么| bnp是什么意思| 清酒和白酒有什么区别| 红参和人参有什么区别| 血糖高的人早餐吃什么最好| 杠杆率是什么意思| 老年人吃什么水果对身体好| st什么意思| 床上放什么可以驱蟑螂| 什么是华盖| 杀鸡取卵是什么生肖| 小腹隐隐作痛是什么原因女性| 纳米是什么意思| 上胸围90下胸围80是什么罩杯| 子宫前位和子宫后位有什么区别| 为国为民是什么生肖| 11.23是什么星座| 化胡为佛是什么意思| 吃什么能让奶水变多| 小孩不吃饭是什么原因| 什么食物含锌最多| 红豆和什么搭配最好| 吃什么去肝火最快| ct什么意思| tp是什么病毒| 哆啦a梦的口袋叫什么| 为什么会长瘊子| 脓毒血症是什么病| 百度
Table of Contents
Basic concepts of character sets and collation
Set several levels of character set and sorting
Frequently Asked Questions and Solutions
The impact of sorting rules selection
Home Database Mysql Tutorial Managing Character Sets and Collations in MySQL

深圳宝安将在各街道建立新时代讲习所

Jul 07, 2025 am 01:41 AM
mysql character set

百度 因此,这说明要更好满足人民日益增长的美好生活需要,就要紧紧扣住发展不平衡不充分,着力破解之。

The setting of character sets and collation rules in MySQL is crucial, affecting data storage, query efficiency and consistency. First, the character set determines the storable character range, such as utf8mb4 supports Chinese and emojis; the sorting rules control the character comparison method, such as utf8mb4_unicode_ci is case-sensitive, and utf8mb4_bin is binary comparison. Secondly, the character set can be set at multiple levels of server, database, table, and column. It is recommended to use utf8mb4 and utf8mb4_unicode_ci to avoid conflicts. Furthermore, the garbled code problem is often caused by inconsistent character sets of connections, storage or program terminals, and needs to be checked layer by layer and set uniformly. Additionally, character sets should be specified when exporting imports to prevent conversion errors. Finally, the sorting rules affect the ORDER BY results, index efficiency and uniqueness judgment, and should be selected according to application needs. If fuzzy searches, case-insensitive sorting rules should be considered. Properly configuring character sets and sorting rules can significantly reduce late maintenance costs.

Managing Character Sets and Collations in MySQL

Character set and collation rules management in MySQL may seem simple, but if you are not careful, you can easily encounter problems such as garbled code, reduced query efficiency and even data loss in actual use. The key is to understand the role level of character sets and sorting rules, and set them reasonably according to application needs.

Managing Character Sets and Collations in MySQL

Basic concepts of character sets and collation

The character set in MySQL determines which characters can be stored in the database. For example, the common utf8mb4 supports Chinese and emojis, while latin1 only supports Western European characters. Collation determines how these characters are compared and sorted. For example, the difference between utf8mb4_unicode_ci and utf8mb4_bin is whether they are case sensitive or use binary comparisons.

Managing Character Sets and Collations in MySQL

You can specify these settings when creating a database, table, or field. If not specified, MySQL uses the default value, which may not be the result you want.

Set several levels of character set and sorting

MySQL supports multiple levels of character set settings:

Managing Character Sets and Collations in MySQL
  • Server level : Set through character_set_server and collation_server in the configuration file
  • Database Level : Use CHARACTER SET and COLLATE when creating a database
  • Table level : Specify CHARSET and COLLATE when creating tables
  • Column level : Set character sets and sorting rules separately when defining fields

It is usually recommended to set it uniformly at the database or table level to avoid conflicts between different levels. For example, most modern applications recommend using utf8mb4 and utf8mb4_unicode_ci , which can be compatible with most languages ??and common characters.

Frequently Asked Questions and Solutions

If you find that the page is displayed with "???" or garbled code, it is likely that the character set is inconsistent. The following are the troubleshooting ideas:

  • Confirm whether the connection character set is correct, you can execute SET NAMES 'utf8mb4' after connection
  • Check the actual character set of databases, tables, and columns, and use SHOW CREATE DATABASE or SHOW CREATE TABLE to view it
  • Verify whether the program terminal sends data in the correct encoding, such as the charset parameter of PDO needs to be set in PHP

One easily overlooked place is the conversion of character sets when exporting imported data. When using mysqldump , add --default-character-set=utf8mb4 can avoid many problems.

The impact of sorting rules selection

The sorting rules not only affect the results of ORDER BY , but also affect the index efficiency and uniqueness judgment. For example:

  • utf8mb4_unicode_ci uses the Unicode standard for comparison, which is more in line with multilingual habits
  • utf8mb4_0900_ci is a newer collation, suitable for MySQL 8.0 and above
  • utf8mb4_bin is compared bytes, strictly distinguishing between case and accents.

If there is a need for fuzzy search in the application, such as matching case-insensitive user names, it is important to choose the appropriate sorting rule. Sometimes different collations are even used on specific fields for balance of performance and accuracy.

Basically that's it. Proper character set and sorting rules can reduce a lot of trouble in later maintenance. Although it seems to be just a few parameters, it has a profound impact.

The above is the detailed content of Managing Character Sets and Collations in MySQL. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
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

Hot AI Tools

Undress AI Tool

Undress AI Tool

Undress images for free

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

PHP Tutorial
1488
72
How to use PHP to develop a Q&A community platform Detailed explanation of PHP interactive community monetization model How to use PHP to develop a Q&A community platform Detailed explanation of PHP interactive community monetization model Jul 23, 2025 pm 07:21 PM

1. The first choice for the Laravel MySQL Vue/React combination in the PHP development question and answer community is the first choice for Laravel MySQL Vue/React combination, due to its maturity in the ecosystem and high development efficiency; 2. High performance requires dependence on cache (Redis), database optimization, CDN and asynchronous queues; 3. Security must be done with input filtering, CSRF protection, HTTPS, password encryption and permission control; 4. Money optional advertising, member subscription, rewards, commissions, knowledge payment and other models, the core is to match community tone and user needs.

Automating MySQL Deployments with Infrastructure as Code Automating MySQL Deployments with Infrastructure as Code Jul 20, 2025 am 01:49 AM

To achieve MySQL deployment automation, the key is to use Terraform to define resources, Ansible management configuration, Git for version control, and strengthen security and permission management. 1. Use Terraform to define MySQL instances, such as the version, type, access control and other resource attributes of AWSRDS; 2. Use AnsiblePlaybook to realize detailed configurations such as database user creation, permission settings, etc.; 3. All configuration files are included in Git management, support change tracking and collaborative development; 4. Avoid hard-coded sensitive information, use Vault or AnsibleVault to manage passwords, and set access control and minimum permission principles.

How to set environment variables in PHP environment Description of adding PHP running environment variables How to set environment variables in PHP environment Description of adding PHP running environment variables Jul 25, 2025 pm 08:33 PM

There are three main ways to set environment variables in PHP: 1. Global configuration through php.ini; 2. Passed through a web server (such as SetEnv of Apache or fastcgi_param of Nginx); 3. Use putenv() function in PHP scripts. Among them, php.ini is suitable for global and infrequently changing configurations, web server configuration is suitable for scenarios that need to be isolated, and putenv() is suitable for temporary variables. Persistence policies include configuration files (such as php.ini or web server configuration), .env files are loaded with dotenv library, and dynamic injection of variables in CI/CD processes. Security management sensitive information should be avoided hard-coded, and it is recommended to use.en

How to use PHP to develop product recommendation module PHP recommendation algorithm and user behavior analysis How to use PHP to develop product recommendation module PHP recommendation algorithm and user behavior analysis Jul 23, 2025 pm 07:00 PM

To collect user behavior data, you need to record browsing, search, purchase and other information into the database through PHP, and clean and analyze it to explore interest preferences; 2. The selection of recommendation algorithms should be determined based on data characteristics: based on content, collaborative filtering, rules or mixed recommendations; 3. Collaborative filtering can be implemented in PHP to calculate user cosine similarity, select K nearest neighbors, weighted prediction scores and recommend high-scoring products; 4. Performance evaluation uses accuracy, recall, F1 value and CTR, conversion rate and verify the effect through A/B tests; 5. Cold start problems can be alleviated through product attributes, user registration information, popular recommendations and expert evaluations; 6. Performance optimization methods include cached recommendation results, asynchronous processing, distributed computing and SQL query optimization, thereby improving recommendation efficiency and user experience.

Securing MySQL Connections with SSL/TLS Encryption Securing MySQL Connections with SSL/TLS Encryption Jul 21, 2025 am 02:08 AM

Why do I need SSL/TLS encryption MySQL connection? Because unencrypted connections may cause sensitive data to be intercepted, enabling SSL/TLS can prevent man-in-the-middle attacks and meet compliance requirements; 2. How to configure SSL/TLS for MySQL? You need to generate a certificate and a private key, modify the configuration file to specify the ssl-ca, ssl-cert and ssl-key paths and restart the service; 3. How to force SSL when the client connects? Implemented by specifying REQUIRESSL or REQUIREX509 when creating a user; 4. Details that are easily overlooked in SSL configuration include certificate path permissions, certificate expiration issues, and client configuration requirements.

How to build an online customer service robot with PHP. PHP intelligent customer service implementation technology How to build an online customer service robot with PHP. PHP intelligent customer service implementation technology Jul 25, 2025 pm 06:57 PM

PHP plays the role of connector and brain center in intelligent customer service, responsible for connecting front-end input, database storage and external AI services; 2. When implementing it, it is necessary to build a multi-layer architecture: the front-end receives user messages, the PHP back-end preprocesses and routes requests, first matches the local knowledge base, and misses, call external AI services such as OpenAI or Dialogflow to obtain intelligent reply; 3. Session management is written to MySQL and other databases by PHP to ensure context continuity; 4. Integrated AI services need to use Guzzle to send HTTP requests, safely store APIKeys, and do a good job of error handling and response analysis; 5. Database design must include sessions, messages, knowledge bases, and user tables, reasonably build indexes, ensure security and performance, and support robot memory

How to develop AI intelligent form system with PHP PHP intelligent form design and analysis How to develop AI intelligent form system with PHP PHP intelligent form design and analysis Jul 25, 2025 pm 05:54 PM

When choosing a suitable PHP framework, you need to consider comprehensively according to project needs: Laravel is suitable for rapid development and provides EloquentORM and Blade template engines, which are convenient for database operation and dynamic form rendering; Symfony is more flexible and suitable for complex systems; CodeIgniter is lightweight and suitable for simple applications with high performance requirements. 2. To ensure the accuracy of AI models, we need to start with high-quality data training, reasonable selection of evaluation indicators (such as accuracy, recall, F1 value), regular performance evaluation and model tuning, and ensure code quality through unit testing and integration testing, while continuously monitoring the input data to prevent data drift. 3. Many measures are required to protect user privacy: encrypt and store sensitive data (such as AES

How to make PHP container support automatic construction? Continuously integrated CI configuration method of PHP environment How to make PHP container support automatic construction? Continuously integrated CI configuration method of PHP environment Jul 25, 2025 pm 08:54 PM

To enable PHP containers to support automatic construction, the core lies in configuring the continuous integration (CI) process. 1. Use Dockerfile to define the PHP environment, including basic image, extension installation, dependency management and permission settings; 2. Configure CI/CD tools such as GitLabCI, and define the build, test and deployment stages through the .gitlab-ci.yml file to achieve automatic construction, testing and deployment; 3. Integrate test frameworks such as PHPUnit to ensure that tests are automatically run after code changes; 4. Use automated deployment strategies such as Kubernetes to define deployment configuration through the deployment.yaml file; 5. Optimize Dockerfile and adopt multi-stage construction

See all articles
乳头瘙痒是什么原因 护士是干什么的 今天过生日是什么星座 帝王术是什么意思 挚爱适合用在什么人
皮肤黑适合什么颜色的衣服 d什么意思 怀孕什么时候可以做b超 kailas是什么牌子 十月二十七是什么星座
甲亢都有什么症状 阳虚是什么 滢是什么意思 秋千为什么叫秋千 官杀旺是什么意思
生殖疱疹用什么药效果好 氟是什么东西 prf是什么意思 顺产和剖腹产有什么区别 双花红棍什么意思
根管治疗是什么意思hcv9jop5ns5r.cn 经络是什么hcv9jop4ns4r.cn 300年前是什么朝代hcv8jop6ns1r.cn 汴去掉三点水念什么hcv9jop2ns6r.cn 葡萄柚是什么hcv9jop1ns1r.cn
男人喜欢什么姿势hcv8jop9ns0r.cn 血糖高什么东西不能吃yanzhenzixun.com 5月14日是什么星座weuuu.com 什么炖排骨好吃zhongyiyatai.com 平滑肌是什么jiuxinfghf.com
三叉神经痛吃什么药效果好hcv9jop1ns0r.cn 10月27日什么星座cl108k.com 猪肚炒什么好吃beikeqingting.com 男人什么时候精子最强hcv9jop4ns6r.cn 孕妇拉肚子是什么原因引起的hcv9jop2ns7r.cn
米果念什么hcv8jop9ns3r.cn 含锶矿泉水有什么好处creativexi.com 子宫筛查主要检查什么hcv8jop1ns0r.cn 1991是什么年hcv8jop5ns8r.cn 艮是什么意思hcv7jop6ns2r.cn
百度