<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[Conceptual Universe]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/KewuaBug</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; KewuaBug]]></copyright><item><title><![CDATA[MySQL优化之Explain命令解读]]></title><link>https://blog.youkuaiyun.com/KewuaBug/article/details/122961323</link><guid>https://blog.youkuaiyun.com/KewuaBug/article/details/122961323</guid><author>KewuaBug</author><pubDate>Wed, 16 Feb 2022 13:21:38 +0800</pubDate><description><![CDATA[文章目录1.id2.select_type3.table4.partitions5.type6.possible_keys7.key8.key_len9.ref10.rows11.filtered12.Extra
使用EXPLAIN关键字可以模拟优化器执行SQL查询语句，从而知道MySQL是 如何处理你的SQL语句的。分析你的查询语句或是表结构的性能瓶颈。
使用方式：Explain+SQL语句
执行如下图:

执行计划后包含以上信息,我们挨个解读:
1.id
SELECT查询的序列号，包含一组数字，表示查询]]></description><category></category></item><item><title><![CDATA[输入框清除“数字“以及“.“之外的字符,并且保留两位小数]]></title><link>https://blog.youkuaiyun.com/KewuaBug/article/details/122958833</link><guid>https://blog.youkuaiyun.com/KewuaBug/article/details/122958833</guid><author>KewuaBug</author><pubDate>Wed, 16 Feb 2022 10:54:20 +0800</pubDate><description><![CDATA[输入框限制


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