简体中文(ZH-CN) English(EN) 繁体中文(ZH-TW) 日本語(JA) 한국어(KO) Melayu(MS) Français(FR) Deutsch(DE)
Home> Backend Development> PHP Tutorial> body text

请问新建表时，这个 KEY 表示什么？

WBOY
Release： 2016-06-23 13:53:44
Original
901 people have browsed it 

CREATE TABLE `users` ( `id` int(11) NOT NULL auto_increment, `yhm` varchar(20) NOT NULL, `mm` varchar(50) default NULL, `wt` varchar(20) NOT NULL, PRIMARY KEY (`id`), KEY `yhm` (`yhm`)) ENGINE=MyISAM
Copy after login

KEY `yhm` (`yhm`) ------ 请问这一句是做什么用的？


回复讨论(解决方案)

KEY `yhm` (`yhm`) 是索引

index 索引。
PRIMARY KEY (`id`), 主?
KEY `yhm` (`yhm`) 普通索引

Related labels：
key New
source：php.cn
Previous article：jpgraph 绘图问题 Next article：php全等()
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
Latest Articles by Author
Latest Issues
How to pass key as select option value in v-for when changed (VueJS) I'm using Vue3 and Bootstrap5. I have a select with multiple options. Now I am displaying ...
From 2023-11-17 08:55:24
0
1
276
The rewritten title is: keyOrKeyArray must be an instance of Firebase\JWT\Key key or an array of Firebase\JWT\Key key in php ci4 {"title":"UnexpectedValueException","type":"UnexpectedV...
From 2023-11-07 16:57:25
0
1
187
How to bind v-model to methods in Vue.js I'm learning vuejs(3). I have this loop:
From 2023-11-05 16:36:26
0
1
193
How to declare data of object array in vue.js + typescript I have this code in vue.js3+typescript, I just want to declare an array of objects in the ...
From 2023-11-02 12:50:34
0
1
280
Hardhat compile error "expected a value of type HttpNetworkConfig" I'm trying to follow the NFT tutorial here. I have set up an account on Alchemy and Metama...
From 2023-10-30 19:02:05
0
1
435
Related Topics
More>
Popular Recommendations
Popular Tutorials
More>
Related Tutorials
Popular Recommendations
Latest courses
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template
About us Disclaimer Sitemap
php.cn：Public welfare online PHP training，Help PHP learners grow quickly！