blocks|key|1679326|text|来自这个相关员额|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1679327|比你需要的多一个索引就是太多了。少一个就太少了。|1679328|我试着去找一个有太多索引是个问题，却什么都找不到的例子|blockquote|1679329|如果您的插入太慢，并且用于读取的索引没有足够快的速度来弥补它，知道您有太多的。|style|BOLD|1679330|entityMap|0|LINK|mutability|MUTABLE|url|https://softwareengineering.stackexchange.com/questions/141052/how-many-indexes-is-too-many-indexes^0|2|6|0|0|0|0|V|7|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|6|7|Y|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|Z|8|@]|9|@]|C|$]]|$1|I|3|J|5|6|7|10|8|@$A|11|B|12|K|L]]|9|@]|C|$]]|$1|M|3|-4|5|6|7|13|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

From <a href="https://softwareengineering.stackexchange.com/questions/141052/how-many-indexes-is-too-many-indexes">this related post</a>:

One more index than you need is too many. One less is too little.

<blockquote>
 I've tried searching for a case where having too many indexes was a
 problem and couldn't really find anything
</blockquote>

You KNOW you have too many if your inserts are too slow, and the index used for reading are not speeding things up enough to make up for it.

blocks|key|1804587|text|如果最终需要索引，最好用表创建它们。这在一定程度上降低了插入速度，但如果您需要它们，它们可能也会出现在那里。如果你知道正确的答案，为什么要等待缓慢的查询？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1804588|反对立即将它们放入索引策略的一个论点是，实际的查询是否会为索引策略提供信息。你似乎对它的用法有很好的了解。|1804589|一定要认识到索引会使某些操作变得更快(特别是select)。但是，它们会使其他操作变慢(特别是insert、update和delete)。出于这个原因，您应该仔细考虑正在进行的索引。|offset|length|style|CODE|1804590|entityMap^0|0|0|M|6|1B|6|1I|6|1P|6|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|N|8|@$F|O|G|P|H|I]|$F|Q|G|R|H|I]|$F|S|G|T|H|I]|$F|U|G|V|H|I]]|9|@]|A|$]]|$1|J|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|K|$]]

If you are going to eventually need the indexes, you might as well create them with the tables. This does somewhat slow down inserts, but they might as well be there if you are going to need them. Why wait for slow queries, if you know the right answer?

One argument against putting them in right away is if the actual queries will inform the indexing strategy. You seem to have a pretty good idea of what the usage will be.

Do recognize that indexes make some operations fast (notably <code>select</code>s). However, they make other operations slower (notably, <code>insert</code>, <code>update</code>, and <code>delete</code>). For this reason you should be thoughtful about the indexes that go on.

blocks|key|1804666|text|当插入、更新、删除表时，索引也需要更新。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1804667|参见此关于索引的文章|offset|length|1804668|entityMap|0|LINK|mutability|MUTABLE|url|https://www.globalknowledge.com/blog/2012/02/23/disadvantages-of-indexing-in-sql-server/^0|0|3|7|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

When you insert, update, delete your table, the index need to updated too.

See this <a href="https://www.globalknowledge.com/blog/2012/02/23/disadvantages-of-indexing-in-sql-server/" rel="nofollow noreferrer">Article about indexing</a>

blocks|key|569140|text|是的，由于索引的原因，插入和更新可能更慢。然而，在我的实践中，这并不是一个常见的问题。您只想添加您知道需要的索引。在解决新问题时等待添加其他索引。需要考虑的一件事是：“如果”索引被遗忘了，而不是必需的，实际上会导致难以跟踪的性能问题。在找到问题索引之后，开发人员必须花费更多的时间来确定应用程序的其他部分是否确实需要索引。直到表达到一定大小时才添加索引。我会严重怀疑这会给你带来任何性能，如果这样的话，我会质疑系统的设计。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|569141|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Yes, inserts and updates could be slower because of an index. However, in my practice this has not been a common problem. You want to add only indexes that you know you are going to need. Wait to add other indexes when addressing new problems. One thing to consider is many times: “What if” indexes are forgotten, not needed and actually cause performance issues that can be hard to track down. After finding the problem index, the developer has to spend additional time determining if the index is actually needed in some other part of the application. As far as waiting to add indexes until a table reaches a certain size. I would seriously doubt that would buy you any performance and if it did I would question the system design.

I'm writing a new feature using new tables on a MySQL database. Is there a performance hit I get by indexing columns (that I'll use for <code>WHERE</code> in <code>SELECT</code> queries) from the beginning or should I wait until my table reaches a considerable size before I start indexing?

Is there such a thing as "over-indexing" a database table?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

文章

问答

视频

学习中心

腾讯云实验室

直播

竞赛

腾讯云代码分析专区

腾讯iOA零信任安全管理系统专区

腾讯云架构师技术同盟交流圈

腾讯云数据库专区

腾讯云顾问专区

腾讯云原生专区

腾讯混元专区

腾讯云TCE专区

腾讯云Lighthouse专区

腾讯云HAI专区

腾讯云Edgeone专区

腾讯云存储专区

腾讯云智能专区

腾讯轻联专区 

腾讯云开发专区

TAPD专区

腾讯轻量云游戏服专区

腾讯云最具价值专家

腾讯云架构师技术同盟

腾讯云创作之星

腾讯云开发者先锋

腾讯云代码助手

云原生构建

TAPD 敏捷项目管理

Cloud Studio

SDK中心

API中心

命令行工具

涵盖代码开发、场景应用、自动测试全流程，助你从零构建专属AI助手

一站式MCP教程库，解锁AI应用新玩法

我正在使用MySQL数据库上的新表编写一个新特性。从一开始，索引列(我将在SELECT查询中使用)是否会影响性能，还是应该等到我的表达到相当大的大小后才开始索引？

问是否存在“过度索引”的数据库表？
EN

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问是否存在“过度索引”的数据库表？EN