<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[JHON07的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/JHON07</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; JHON07]]></copyright><item><title><![CDATA[AIvibecoding 微信小程序AI记账熊宝]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/161262738</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/161262738</guid><author>JHON07</author><pubDate>Wed, 20 May 2026 19:04:31 +0800</pubDate><description><![CDATA[AI vibecoding 微信小程序 AI记账熊宝]]></description><category></category></item><item><title><![CDATA[letcode的Java算法题]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156344223</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156344223</guid><author>JHON07</author><pubDate>Sun, 28 Dec 2025 01:07:20 +0800</pubDate><description><![CDATA[每间房内都藏有一定的现金，影响你偷窃的唯一制约因素就是相邻的房屋装有相互连通的防盗系统，如果两间相邻的房屋在同一晚上被小偷闯入，系统会自动报警。解释：偷窃 1 号房屋 (金额 = 2), 偷窃 3 号房屋 (金额 = 9)，接着偷窃 5 号房屋 (金额 = 1)。给定一个代表每个房屋存放金额的非负整数数组，计算你 不触动警报装置的情况下 ，一夜之内能够偷窃到的最高金额。解释：偷窃 1 号房屋 (金额 = 1) ，然后偷窃 3 号房屋 (金额 = 3)。输入：[2,7,9,3,1]输入：[1,2,3,1]]]></description><category></category></item><item><title><![CDATA[letcode数据库题联系]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156269443</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156269443</guid><author>JHON07</author><pubDate>Thu, 25 Dec 2025 14:15:12 +0800</pubDate><description><![CDATA[编写解决方案，筛选出过去一年中订单总量 少于 10 本 的 书籍，并且 不考虑 上架距今销售 不满一个月 的书籍。假设今天是 2019-06-23。book_id  是 Books 表的外键（reference 列）。首先需要明确是查询 book 书籍，books是主表这个是容易忽视的点。order_id 是这个表的主键（具有唯一值的列）。book_id 是这个表的主键（具有唯一值的列）。返回结果表 无顺序要求。]]></description><category></category></item><item><title><![CDATA[健康知识分享]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156100021</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156100021</guid><author>JHON07</author><pubDate>Sat, 20 Dec 2025 01:04:37 +0800</pubDate><description><![CDATA[]]></description><category></category></item><item><title><![CDATA[gradle使用]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156099892</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156099892</guid><author>JHON07</author><pubDate>Sat, 20 Dec 2025 00:48:57 +0800</pubDate><description><![CDATA[Spring Boot 使用自定义的 Gradle 插件来统一管理依赖：text。]]></description><category></category></item><item><title><![CDATA[oracle数据库使用]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156079464</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156079464</guid><author>JHON07</author><pubDate>Fri, 19 Dec 2025 12:58:45 +0800</pubDate><description><![CDATA[C:\Users\钱学林\AppData\Roaming\Typora\typora-user-images\image-20250326164643205.pngC:\Users\钱学林\AppData\Roaming\Typora\typora-user-images\image-20250326170148174.png。]]></description><category></category></item><item><title><![CDATA[mysql面试题整理]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156025319</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156025319</guid><author>JHON07</author><pubDate>Wed, 17 Dec 2025 18:48:50 +0800</pubDate><description><![CDATA[在 MySQL 面试中，MVCC（Multi-Version Concurrency Control，多版本并发控制）是一个高频考点，主要考察候选人对事务隔离级别和并发控制机制的理解。]]></description><category></category></item><item><title><![CDATA[PostgreSQL数据库]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/156025260</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/156025260</guid><author>JHON07</author><pubDate>Wed, 17 Dec 2025 18:41:37 +0800</pubDate><description><![CDATA[xmin是 PostgreSQL 中每个元组（行）的系统字段记录创建该元组的事务 ID (XID)当插入新行时，该行的xmin被设置为当前事务的 XIDPostgreSQL 的 MVCC 通过维护多版本数据，实现了高效的读写并发控制，但也带来存储管理和事务ID回卷的挑战。合理配置 Vacuum、监控长事务、理解事务隔离级别是优化 PostgreSQL 性能的关键。PostgreSQL 的优化需要从多个层面综合考虑，包括硬件、配置、架构设计、查询优化、索引策略和维护管理等。1. 硬件与操作系统优化。]]></description><category></category></item><item><title><![CDATA[jdk源码解析]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/155974890</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/155974890</guid><author>JHON07</author><pubDate>Tue, 16 Dec 2025 12:21:43 +0800</pubDate><description><![CDATA[大家可以多看源码，看一下同样的功能，代码是如何构造的；]]></description><category></category></item><item><title><![CDATA[设计java高并安全类]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/155890185</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/155890185</guid><author>JHON07</author><pubDate>Sat, 13 Dec 2025 22:13:56 +0800</pubDate><description><![CDATA[java 设计线程安全的类]]></description><category></category></item><item><title><![CDATA[Spring AI Alibaba 1.1版本]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/155860269</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/155860269</guid><author>JHON07</author><pubDate>Fri, 12 Dec 2025 17:27:55 +0800</pubDate><description><![CDATA[springalibaba  aiagment]]></description><category></category></item><item><title><![CDATA[.java代码优化]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/155480997</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/155480997</guid><author>JHON07</author><pubDate>Tue, 02 Dec 2025 14:19:55 +0800</pubDate><description><![CDATA[Java 泛型泛型概述Java 泛型（Generics）是 JDK 5 引入的特性，允许在定义类、接口、方法时使用类型参数，提供编译期的类型安全检查，减少类型转换。主要作用：类型安全：编译时检查类型匹配消除强制类型转换提高代码复用性java// 泛型类// 使用// 无需类型转换2. 类型擦除（Type Erasure）什么是类型擦除？]]></description><category></category></item><item><title><![CDATA[mysql优化]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/155480347</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/155480347</guid><author>JHON07</author><pubDate>Tue, 02 Dec 2025 08:38:45 +0800</pubDate><description><![CDATA[主键索引: InnoDB 主键是默认的索引，数据列不允许重复，不允许为 NULL，⼀个表只能有⼀个。唯⼀索引: 数据列不允许重复，允许为 NULL 值，⼀个表允许多个列创建唯⼀索引。Using temporary ：表⽰对查询结果排序时会使⽤⼀个临时表。Using index：表⽰ MySQL 将使⽤覆盖索引，以避免回表。普通索引: 基本的索引类型，没有唯⼀性的限制，允许为 NULL 值。组合索引：多列值组成⼀个索引，⽤于组合搜索，效率⼤于索引合并。]]></description><category></category></item><item><title><![CDATA[idea切换分支以后，项目中的代码不加载了]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/154619488</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/154619488</guid><author>JHON07</author><pubDate>Mon, 10 Nov 2025 11:49:43 +0800</pubDate><description><![CDATA[idea工具使用]]></description><category></category></item><item><title><![CDATA[MySQL - binlog日志简介及设置]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/88674204</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/88674204</guid><author>JHON07</author><pubDate>Mon, 10 Nov 2025 11:44:44 +0800</pubDate><description><![CDATA[前言

mysql-binlog是MySQL数据库的二进制日志，用于记录用户对数据库操作的SQL语句（(除了数据查询语句）信息。可以使用mysqlbin命令查看二进制日志的内容。





MySQL binlog格式



binlog的格式也有三种：STATEMENT、ROW、MIXED 。



1、STATMENT模式：基于SQL语句的复制(statement-based repli...]]></description><category></category></item><item><title><![CDATA[数据库中常用的窗口函数]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/147621159</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/147621159</guid><author>JHON07</author><pubDate>Tue, 29 Apr 2025 22:42:10 +0800</pubDate><description><![CDATA[窗口函数的名字是over() 常用的有两个属性，partition by 和order by ,partition by 类似于group by 函数，通常称 group by 为分组，partition by 称为分区  ，分组通常是返回一行，分区是返回多行，比如你对人说自己是10名，可能没有什么，如果是100000中的第10名，那就是前1/1000000 那就非常的牛了。如果有一个行的pecent_rank正好等于N,那么就是这个值。将排序后的数据均匀分配的指定的数据桶中，返回桶编号，如果不能等分。]]></description><category></category></item><item><title><![CDATA[实现窗口函数]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/147356455</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/147356455</guid><author>JHON07</author><pubDate>Sat, 19 Apr 2025 21:52:35 +0800</pubDate><description><![CDATA[【代码】实现窗口函数。]]></description><category></category></item><item><title><![CDATA[java 进阶相关知识]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/130914122</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/130914122</guid><author>JHON07</author><pubDate>Sun, 28 May 2023 22:32:25 +0800</pubDate><description><![CDATA[jvm 相关知识]]></description><category></category></item><item><title><![CDATA[堆的概念和算法]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/130780195</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/130780195</guid><author>JHON07</author><pubDate>Sat, 20 May 2023 14:24:04 +0800</pubDate><description><![CDATA[堆和队列]]></description><category></category></item><item><title><![CDATA[select for update和select for update wait和select for update nowait的区别]]></title><link>https://blog.youkuaiyun.com/JHON07/article/details/120025070</link><guid>https://blog.youkuaiyun.com/JHON07/article/details/120025070</guid><author>JHON07</author><pubDate>Sat, 15 Apr 2023 00:30:02 +0800</pubDate><description><![CDATA[oracle  for update ]]></description><category></category></item></channel></rss>