Community Learn Tools Library Leisure
search
English
Home > Database > Mysql Tutorial > mysql5.1和mysql5.5创建索引速度对比

mysql5.1和mysql5.5创建索引速度对比

WBOY
Release： 2016-06-07 17:40:43
Original
1230 people have browsed it

在MySQL5.1.X版本里，聚集索引创建和删除的过程：1、创建一个和原表结构一样的空表，然后创建聚集索引;2、拷贝原表的数据到新表，这时会对原表加一个排他锁，其

3、 复制完毕后删除掉原表，并把新表改名为原表。 

3、复制完毕后删除掉原表，并把新表改名为原表。

在MySQL5.5.X版本开始， 创建和删除非聚集索引不用复制整个表的内容，

只需更新索引页，和之前相比，速度会更快。但创建聚集索引（主键）时，网站空间，或者是外键时，香港空间，还是需要复制整个表的内容，因为聚集索引是把 primary key 以及 row data 保存在一起的，免备案空间，而 secondary index 则是单独存放，然后有个指针指向 primary key。

下面是创建非聚集索引的速度对比：

参见MySQL5.5手册：

 

本文出自 “贺春旸的技术专栏” 博客，请务必保留此出处

Related labels：
index
source：php.cn
Previous article： SQL 必知必会笔记3过滤数据 Next article： T-SQL时间、字符串函数
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
The query and formula form the entire table, with new columns, where the new columns are formulas involving other conditional column values EDIT: The formula should be the "value" column - the "value" column wi...
From 2024-04-06 21:23:40
0
2
530
Laravel 8 - How to redirect /{editable_text} route to /{user} route I've been trying to create a redirect route to lead me to a user profile. The redirect rou...
From 2024-04-06 17:26:11
0
1
410
Why is my hr tag translucent when it is set to a solid color of white? I have a html (with bootstrap) and a css, in my html I have a <hr> tag which has a c...
From 2024-04-06 16:13:26
0
1
500
Regular expression filter for MERN stack search boxes and checkboxes I'm trying to understand how the MERN stack works together by learning by doing, and I'm f...
From 2024-04-06 14:53:12
0
1
425
Hide/show div on click and scroll I want to create a hidden search form that appears when we click on the search icon and hi...
From 2024-04-06 12:20:46
0
1
386
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