You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 

64 lines
80 KiB

<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width"><meta name="theme-color" content="#222"><meta name="generator" content="Hexo 6.3.0"><link rel="preconnect" href="https://fonts.googleapis.com" crossorigin><link rel="preconnect" href="https://cdnjs.cloudflare.com" crossorigin><link rel="apple-touch-icon" sizes="180x180" href="/images/apple-touch-icon-next.png"><link rel="icon" type="image/png" sizes="32x32" href="/images/favicon-32x32-next.png"><link rel="icon" type="image/png" sizes="16x16" href="/images/favicon-16x16-next.png"><link rel="mask-icon" href="/images/logo.svg" color="#222"><meta name="google-site-verification" content="2X6S9P7CAjXjVvw8YyQR8pCu-B0oEu7O9quLgxXuWyA"><meta name="baidu-site-verification" content="dV8JGNzi0c"><script>setTimeout(function(){var d=document.createElement("script");d.setAttribute("data-ad-client","ca-pub-7480618470784058"),d.async=!0,d.src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js",document.body.appendChild(d)},5e3),window.addEventListener?window.addEventListener("load",downloadJsAtOnload,!1):window.attachEvent?window.attachEvent("onload",downloadJsAtOnload):window.onload=downloadJsAtOnload</script><link rel="stylesheet" href="/css/main.css"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Lato:300,300italic,400,400italic,700,700italic&display=swap&subset=latin,latin-ext"><link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.1.1/css/all.min.css" integrity="sha256-DfWjNxDkM94fVBWx1H5BMMp0Zq7luBlV8QRcSES7s+0=" crossorigin="anonymous"><link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/fancybox/3.5.7/jquery.fancybox.min.css" integrity="sha256-Vzbj7sDDS/woiFS3uNKo8eIuni59rjyNGtXfstRzStA=" crossorigin="anonymous"><script class="next-config" data-name="main" type="application/json">{"hostname":"nicksxs.me","root":"/","images":"/images","scheme":"Pisces","darkmode":false,"version":"8.12.1","exturl":false,"sidebar":{"position":"left","display":"post","padding":18,"offset":12},"copycode":{"enable":true,"style":"mac"},"bookmark":{"enable":false,"color":"#222","save":"auto"},"mediumzoom":false,"lazyload":true,"pangu":false,"comments":{"style":"tabs","active":null,"storage":true,"lazyload":false,"nav":null},"stickytabs":false,"motion":{"enable":false,"async":false,"transition":{"post_block":"fadeIn","post_header":"fadeInDown","post_body":"fadeInDown","coll_header":"fadeInLeft","sidebar":"fadeInUp"}},"prism":false,"i18n":{"placeholder":"搜索...","empty":"没有找到任何搜索结果:${query}","hits_time":"找到 ${hits} 个搜索结果(用时 ${time} 毫秒)","hits":"找到 ${hits} 个搜索结果"},"path":"/search.xml","localsearch":{"enable":true,"trigger":"auto","top_n_per_article":1,"unescape":true,"preload":true}}</script><script src="/js/config.js"></script><meta name="description" content="前面在聊 Sharding-Jdbc 的时候看到了一篇文章,关于一个分页的查询,一直比较直接的想法就是分库分表下的分页是非常不合理的,一般我们的实操方案都是分表加上 ES 搜索做分页,或者通过合表读写分离的方案,因为对于 sharding-jdbc 如果没有带分表键,查询基本都是只能在所有分表都执行一遍,然后再加上分页,基本上是分页越大后续的查询越耗资源,但是仔细的去想这个细节还是这次,就简单说说"><meta property="og:type" content="article"><meta property="og:title" content="聊聊 Sharding-Jdbc 分库分表下的分页方案"><meta property="og:url" content="https://nicksxs.me/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/index.html"><meta property="og:site_name" content="Nicksxs&#39;s Blog"><meta property="og:description" content="前面在聊 Sharding-Jdbc 的时候看到了一篇文章,关于一个分页的查询,一直比较直接的想法就是分库分表下的分页是非常不合理的,一般我们的实操方案都是分表加上 ES 搜索做分页,或者通过合表读写分离的方案,因为对于 sharding-jdbc 如果没有带分表键,查询基本都是只能在所有分表都执行一遍,然后再加上分页,基本上是分页越大后续的查询越耗资源,但是仔细的去想这个细节还是这次,就简单说说"><meta property="og:locale" content="zh_CN"><meta property="og:image" content="https://img.nicksxs.com/uPic/Gj7TPq.png"><meta property="article:published_time" content="2022-01-09T12:02:49.000Z"><meta property="article:modified_time" content="2022-06-11T14:45:11.000Z"><meta property="article:author" content="Nicksxs"><meta property="article:tag" content="Java"><meta property="article:tag" content="Sharding-Jdbc"><meta name="twitter:card" content="summary"><meta name="twitter:image" content="https://img.nicksxs.com/uPic/Gj7TPq.png"><link rel="canonical" href="https://nicksxs.me/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/"><script class="next-config" data-name="page" type="application/json">{"sidebar":"","isHome":false,"isPost":true,"lang":"zh-CN","comments":true,"permalink":"https://nicksxs.me/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/","path":"2022/01/09/聊聊-Sharding-Jdbc-分库分表下的分页方案/","title":"聊聊 Sharding-Jdbc 分库分表下的分页方案"}</script><script class="next-config" data-name="calendar" type="application/json">""</script><title>聊聊 Sharding-Jdbc 分库分表下的分页方案 | Nicksxs's Blog</title><script async src="https://www.googletagmanager.com/gtag/js?id=UA-61358619-1"></script><script class="next-config" data-name="google_analytics" type="application/json">{"tracking_id":"UA-61358619-1","only_pageview":false}</script><script src="/js/third-party/analytics/google-analytics.js"></script><script src="/js/third-party/analytics/baidu-analytics.js"></script><script async src="https://hm.baidu.com/hm.js?20f33b3c0c0eff9b1522999c0015646d"></script><noscript><link rel="stylesheet" href="/css/noscript.css"></noscript><link rel="alternate" href="/atom.xml" title="Nicksxs's Blog" type="application/atom+xml"></head><body itemscope itemtype="http://schema.org/WebPage"><div class="headband"></div><main class="main"><header class="header" itemscope itemtype="http://schema.org/WPHeader"><div class="header-inner"><div class="site-brand-container"><div class="site-nav-toggle"><div class="toggle" aria-label="切换导航栏" role="button"><span class="toggle-line"></span> <span class="toggle-line"></span> <span class="toggle-line"></span></div></div><div class="site-meta"><a href="/" class="brand" rel="start"><i class="logo-line"></i><p class="site-title">Nicksxs's Blog</p><i class="logo-line"></i></a><p class="site-subtitle" itemprop="description">What hurts more, the pain of hard work or the pain of regret?</p></div><div class="site-nav-right"><div class="toggle popup-trigger"><i class="fa fa-search fa-fw fa-lg"></i></div></div></div><nav class="site-nav"><ul class="main-menu menu"><li class="menu-item menu-item-home"><a href="/" rel="section"><i class="fa fa-home fa-fw"></i>首页</a></li><li class="menu-item menu-item-about"><a href="/about/" rel="section"><i class="fa fa-user fa-fw"></i>关于</a></li><li class="menu-item menu-item-tags"><a href="/tags/" rel="section"><i class="fa fa-tags fa-fw"></i>标签</a></li><li class="menu-item menu-item-categories"><a href="/categories/" rel="section"><i class="fa fa-th fa-fw"></i>分类</a></li><li class="menu-item menu-item-archives"><a href="/archives/" rel="section"><i class="fa fa-archive fa-fw"></i>归档</a></li><li class="menu-item menu-item-top"><a href="/top/" rel="section"><i class="fa fa-th fa-fw"></i>热度</a></li><li class="menu-item menu-item-sitemap"><a href="/sitemap.xml" rel="section"><i class="fa fa-sitemap fa-fw"></i>站点地图</a></li><li class="menu-item menu-item-commonweal"><a href="/404/" rel="section"><i class="fa fa-heartbeat fa-fw"></i>公益 404</a></li><li class="menu-item menu-item-search"><a role="button" class="popup-trigger"><i class="fa fa-search fa-fw"></i>搜索</a></li></ul></nav><div class="search-pop-overlay"><div class="popup search-popup"><div class="search-header"><span class="search-icon"><i class="fa fa-search"></i></span><div class="search-input-container"><input autocomplete="off" autocapitalize="off" maxlength="80" placeholder="搜索..." spellcheck="false" type="search" class="search-input"></div><span class="popup-btn-close" role="button"><i class="fa fa-times-circle"></i></span></div><div class="search-result-container no-result"><div class="search-result-icon"><i class="fa fa-spinner fa-pulse fa-5x"></i></div></div></div></div></div><div class="toggle sidebar-toggle" role="button"><span class="toggle-line"></span> <span class="toggle-line"></span> <span class="toggle-line"></span></div><aside class="sidebar"><div class="sidebar-inner sidebar-overview-active"><ul class="sidebar-nav"><li class="sidebar-nav-toc">文章目录</li><li class="sidebar-nav-overview">站点概览</li></ul><div class="sidebar-panel-container"><div class="post-toc-wrap sidebar-panel"></div><div class="site-overview-wrap sidebar-panel"><div class="site-author site-overview-item animated" itemprop="author" itemscope itemtype="http://schema.org/Person"><img class="site-author-image" itemprop="image" alt="Nicksxs" src="/uploads/avatar.jpg"><p class="site-author-name" itemprop="name">Nicksxs</p><div class="site-description" itemprop="description">learn from zero,技术博客,Nicksxs,史学森</div></div><div class="site-state-wrap site-overview-item animated"><nav class="site-state"><div class="site-state-item site-state-posts"><a href="/archives/"><span class="site-state-item-count">188</span> <span class="site-state-item-name">日志</span></a></div><div class="site-state-item site-state-categories"><a href="/categories/"><span class="site-state-item-count">148</span> <span class="site-state-item-name">分类</span></a></div><div class="site-state-item site-state-tags"><a href="/tags/"><span class="site-state-item-count">285</span> <span class="site-state-item-name">标签</span></a></div></nav></div><div class="links-of-author site-overview-item animated"><span class="links-of-author-item"><a href="https://github.com/nicksxs" title="GitHub → https:&#x2F;&#x2F;github.com&#x2F;nicksxs" rel="noopener" target="_blank"><i class="fab fa-github fa-fw"></i>GitHub</a> </span><span class="links-of-author-item"><a href="mailto:nicksxs1202@gmail.com" title="E-Mail → mailto:nicksxs1202@gmail.com" rel="noopener" target="_blank"><i class="fa fa-envelope fa-fw"></i>E-Mail</a></span></div><div class="cc-license site-overview-item animated" itemprop="license"><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" class="cc-opacity" rel="noopener" target="_blank"><img src="https://cdnjs.cloudflare.com/ajax/libs/creativecommons-vocabulary/2020.11.3/assets/license_badges/small/by_nc_sa.svg" alt="Creative Commons"></a></div><script charset="utf-8" src="/js/tagcloud.js"></script><script charset="utf-8" src="/js/tagcanvas.js"></script><div class="widget-wrap"><div id="myCanvasContainer" class="widget tagcloud"><canvas width="250" height="250" id="resCanvas"><ul class="tag-list" itemprop="keywords"><li class="tag-list-item"><a class="tag-list-link" href="/tags/2019/" rel="tag">2019</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/2020/" rel="tag">2020</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/2021/" rel="tag">2021</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/2PC/" rel="tag">2PC</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/360-%E5%85%A8%E5%AE%B6%E6%A1%B6/" rel="tag">360 全家桶</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/3PC/" rel="tag">3PC</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/3Sum-Closest/" rel="tag">3Sum Closest</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/AOP/" rel="tag">AOP</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Adaptive/" rel="tag">Adaptive</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Apollo/" rel="tag">Apollo</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/AutoConfiguration/" rel="tag">AutoConfiguration</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Binary-Tree/" rel="tag">Binary Tree</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Broker/" rel="tag">Broker</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/C/" rel="tag">C</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/C/" rel="tag">C++</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/CachedThreadPool/" rel="tag">CachedThreadPool</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Comparator/" rel="tag">Comparator</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/DFS/" rel="tag">DFS</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/DP/" rel="tag">DP</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/DefaultMQPushConsumer/" rel="tag">DefaultMQPushConsumer</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Design-Patterns/" rel="tag">Design Patterns</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Disruptor/" rel="tag">Disruptor</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Distributed-Lock/" rel="tag">Distributed Lock</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Docker/" rel="tag">Docker</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Dockerfile/" rel="tag">Dockerfile</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Druid/" rel="tag">Druid</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Dubbo/" rel="tag">Dubbo</a><span class="tag-list-count">6</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/EagerThreadPool/" rel="tag">EagerThreadPool</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Evict/" rel="tag">Evict</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Filter/" rel="tag">Filter</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/First-Bad-Version/" rel="tag">First Bad Version</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/FixedThreadPool/" rel="tag">FixedThreadPool</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/G1/" rel="tag">G1</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/GC/" rel="tag">GC</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Garbage-First-Collector/" rel="tag">Garbage-First Collector</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Gogs/" rel="tag">Gogs</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Homebrew/" rel="tag">Homebrew</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Inorder-Traversal/" rel="tag">Inorder Traversal</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Interceptor/" rel="tag">Interceptor</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Intersection-of-Two-Arrays/" rel="tag">Intersection of Two Arrays</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/JMap/" rel="tag">JMap</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/JPS/" rel="tag">JPS</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/JStack/" rel="tag">JStack</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/JVM/" rel="tag">JVM</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Java/" rel="tag">Java</a><span class="tag-list-count">36</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Leetcode-42/" rel="tag">Leetcode 42</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/LimitedThreadPool/" rel="tag">LimitedThreadPool</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Linked-List/" rel="tag">Linked List</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Lowest-Common-Ancestor-of-a-Binary-Tree/" rel="tag">Lowest Common Ancestor of a Binary Tree</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/MQ/" rel="tag">MQ</a><span class="tag-list-count">9</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Mac/" rel="tag">Mac</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Maven/" rel="tag">Maven</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Median-of-Two-Sorted-Arrays/" rel="tag">Median of Two Sorted Arrays</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Mybatis/" rel="tag">Mybatis</a><span class="tag-list-count">5</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Mysql/" rel="tag">Mysql</a><span class="tag-list-count">5</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/NameServer/" rel="tag">NameServer</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/PHP/" rel="tag">PHP</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Preorder-Traversal/" rel="tag">Preorder Traversal</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Print-FooBar-Alternately/" rel="tag">Print FooBar Alternately</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/RPC/" rel="tag">RPC</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Redis/" rel="tag">Redis</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Remove-Duplicates-from-Sorted-List/" rel="tag">Remove Duplicates from Sorted List</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/RocketMQ/" rel="tag">RocketMQ</a><span class="tag-list-count">9</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Rotate-Image/" rel="tag">Rotate Image</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Rust/" rel="tag">Rust</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/SPI/" rel="tag">SPI</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Servlet/" rel="tag">Servlet</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Sharding-Jdbc/" rel="tag">Sharding-Jdbc</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Shift-2D-Grid/" rel="tag">Shift 2D Grid</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Singleton/" rel="tag">Singleton</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Spring/" rel="tag">Spring</a><span class="tag-list-count">6</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Spring-Event/" rel="tag">Spring Event</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/SpringBoot/" rel="tag">SpringBoot</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Sql%E6%B3%A8%E5%85%A5/" rel="tag">Sql注入</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Stream/" rel="tag">Stream</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Synchronized/" rel="tag">Synchronized</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Thread-dump/" rel="tag">Thread dump</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/ThreadLocal/" rel="tag">ThreadLocal</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/ThreadPool/" rel="tag">ThreadPool</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Tomcat/" rel="tag">Tomcat</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Trapping-Rain-Water/" rel="tag">Trapping Rain Water</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/WeakReference/" rel="tag">WeakReference</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Web/" rel="tag">Web</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/Webhook/" rel="tag">Webhook</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/WordPress/" rel="tag">WordPress</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/aqs/" rel="tag">aqs</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/await/" rel="tag">await</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/bloom-filter/" rel="tag">bloom filter</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/c/" rel="tag">c++</a><span class="tag-list-count">14</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/cglib/" rel="tag">cglib</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/cgroup/" rel="tag">cgroup</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/cluster/" rel="tag">cluster</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/condition/" rel="tag">condition</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/docker/" rel="tag">docker</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/dp/" rel="tag">dp</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/dubbo/" rel="tag">dubbo</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/echo/" rel="tag">echo</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/environment/" rel="tag">environment</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/gap-lock/" rel="tag">gap lock</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/gc/" rel="tag">gc</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/git/" rel="tag">git</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/grep/" rel="tag">grep</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/hadoop/" rel="tag">hadoop</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/icu4c/" rel="tag">icu4c</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/im/" rel="tag">im</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/is-not-null/" rel="tag">is not null</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/is-null/" rel="tag">is null</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/j-u-c/" rel="tag">j.u.c</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/java/" rel="tag">java</a><span class="tag-list-count">33</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/jvm/" rel="tag">jvm</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/leetcode/" rel="tag">leetcode</a><span class="tag-list-count">40</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/leetcode-155/" rel="tag">leetcode 155</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/linked-list/" rel="tag">linked list</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/linux/" rel="tag">linux</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/lock/" rel="tag">lock</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/mfc/" rel="tag">mfc</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/min-stack/" rel="tag">min stack</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/mq/" rel="tag">mq</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/mvcc/" rel="tag">mvcc</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/mysql/" rel="tag">mysql</a><span class="tag-list-count">6</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/namespace/" rel="tag">namespace</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/next-key-lock/" rel="tag">next-key lock</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/nginx/" rel="tag">nginx</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/nullsfirst/" rel="tag">nullsfirst</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/openresty/" rel="tag">openresty</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/php/" rel="tag">php</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/powershell/" rel="tag">powershell</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/procedure/" rel="tag">procedure</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/python/" rel="tag">python</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/read-view/" rel="tag">read view</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/redis/" rel="tag">redis</a><span class="tag-list-count">12</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/scp/" rel="tag">scp</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/signal/" rel="tag">signal</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/sort/" rel="tag">sort</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/spark/" rel="tag">spark</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/ssh/" rel="tag">ssh</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/stack/" rel="tag">stack</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/stream/" rel="tag">stream</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/string/" rel="tag">string</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/swoole/" rel="tag">swoole</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/top/" rel="tag">top</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/uname/" rel="tag">uname</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/unlock/" rel="tag">unlock</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/utf8/" rel="tag">utf8</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/utf8mb4/" rel="tag">utf8mb4</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/utf8mb4-0900-ai-ci/" rel="tag">utf8mb4_0900_ai_ci</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/utf8mb4-general-ci/" rel="tag">utf8mb4_general_ci</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/utf8mb4-unicode-ci/" rel="tag">utf8mb4_unicode_ci</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/value/" rel="tag">value</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/websocket/" rel="tag">websocket</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/zookeeper/" rel="tag">zookeeper</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/zsh/" rel="tag">zsh</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%89%E9%98%B6%E6%AE%B5%E6%8F%90%E4%BA%A4/" rel="tag">三阶段提交</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%8D%E5%8F%AF%E5%8F%98%E5%BC%95%E7%94%A8/" rel="tag">不可变引用</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%9C%E4%BA%AC%E5%A5%A5%E8%BF%90%E4%BC%9A/" rel="tag">东京奥运会</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%A4%E9%98%B6%E6%AE%B5%E6%8F%90%E4%BA%A4/" rel="tag">两阶段提交</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%AD%E5%B1%B1%E8%B7%AF/" rel="tag">中山路</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%AD%E5%BA%8F/" rel="tag">中序</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%AD%E9%97%B4%E4%BB%B6/" rel="tag">中间件</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B8%BE%E9%87%8D/" rel="tag">举重</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%B9%92%E4%B9%93%E7%90%83/" rel="tag">乒乓球</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%BA%8B%E5%8A%A1/" rel="tag">事务</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%BA%8C%E5%8F%89%E6%A0%91/" rel="tag">二叉树</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%BA%92%E6%96%A5%E9%94%81/" rel="tag">互斥锁</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%BB%A3%E7%A0%81%E9%A2%98%E8%A7%A3/" rel="tag">代码题解</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E4%BF%AE%E7%94%B5%E8%84%91%E7%9A%84/" rel="tag">修电脑的</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%81%8F%E5%90%91%E9%94%81/" rel="tag">偏向锁</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%81%A5%E5%BA%B7%E7%A0%81/" rel="tag">健康码</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%85%AC%E4%BA%A4/" rel="tag">公交</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%85%AC%E4%BA%A4%E8%BD%A6/" rel="tag">公交车</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%86%85%E5%AD%98%E5%88%86%E5%B8%83/" rel="tag">内存分布</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%86%85%E5%AD%98%E6%B3%84%E6%BC%8F/" rel="tag">内存泄漏</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%87%86%E5%A4%87/" rel="tag">准备</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%87%8F%E8%82%A5/" rel="tag">减肥</a><span class="tag-list-count">6</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%88%86%E5%B8%83%E5%BC%8F%E4%BA%8B%E5%8A%A1/" rel="tag">分布式事务</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%88%86%E5%B8%83%E5%BC%8F%E9%94%81/" rel="tag">分布式锁</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%88%87%E7%89%87/" rel="tag">切片</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%88%9D%E5%A7%8B%E5%8C%96/" rel="tag">初始化</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%89%8A%E5%B3%B0%E5%A1%AB%E8%B0%B7/" rel="tag">削峰填谷</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%89%8D%E5%BA%8F/" rel="tag">前序</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8A%A0%E5%A1%9E/" rel="tag">加塞</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8A%A0%E8%BD%BD/" rel="tag">加载</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8D%95%E4%BE%8B/" rel="tag">单例</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8D%9A%E5%AE%A2%EF%BC%8C%E6%96%87%E7%AB%A0/" rel="tag">博客,文章</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8E%A6%E9%97%A8/" rel="tag">厦门</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8F%8C%E4%BA%B2%E5%A7%94%E6%B4%BE/" rel="tag">双亲委派</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8F%91%E8%A1%8C%E7%89%88/" rel="tag">发行版</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8F%A3%E7%BD%A9/" rel="tag">口罩</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%8F%AF%E5%8F%98%E5%BC%95%E7%94%A8/" rel="tag">可变引用</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%90%90%E6%A7%BD/" rel="tag">吐槽</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%9B%A4%E7%89%A9%E8%B5%84/" rel="tag">囤物资</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%9E%83%E5%9C%BE%E5%9B%9E%E6%94%B6/" rel="tag">垃圾回收</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%9F%BA%E7%A1%80%E8%AE%BE%E6%96%BD/" rel="tag">基础设施</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%A4%A7%E6%89%AB%E9%99%A4/" rel="tag">大扫除</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%AD%97%E7%AC%A6%E9%9B%86/" rel="tag">字符集</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%AE%89%E5%85%A8/" rel="tag">安全</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%AE%B9%E9%94%99%E6%9C%BA%E5%88%B6/" rel="tag">容错机制</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%AF%84%E7%94%9F%E8%99%AB/" rel="tag">寄生虫</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B0%84%E5%87%BB/" rel="tag">射击</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B0%8F%E6%8A%80%E5%B7%A7/" rel="tag">小技巧</a><span class="tag-list-count">5</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B1%80%E5%8F%A3%E8%A1%97/" rel="tag">局口街</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B8%83%E9%9A%86%E8%BF%87%E6%BB%A4%E5%99%A8/" rel="tag">布隆过滤器</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B9%B2%E6%B4%BB/" rel="tag">干活</a><span class="tag-list-count">5</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B9%B4%E4%B8%AD%E6%80%BB%E7%BB%93/" rel="tag">年中总结</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B9%B4%E7%BB%88%E6%80%BB%E7%BB%93/" rel="tag">年终总结</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B9%B6%E5%8F%91/" rel="tag">并发</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B9%B8%E7%A6%8F%E4%BA%86%E5%90%97/" rel="tag">幸福了吗</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%B9%BB%E8%AF%BB/" rel="tag">幻读</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%BA%94%E7%94%A8/" rel="tag">应用</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%BC%80%E8%BD%A6/" rel="tag">开车</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%BC%B1%E5%BC%95%E7%94%A8/" rel="tag">弱引用</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E5%BD%B1%E8%AF%84/" rel="tag">影评</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%89%80%E6%9C%89%E6%9D%83/" rel="tag">所有权</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%89%93%E5%8D%A1/" rel="tag">打卡</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%89%B6%E6%A2%AF/" rel="tag">扶梯</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%8A%80%E6%9C%AF/" rel="tag">技术</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%8B%96%E6%9B%B4/" rel="tag">拖更</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%8D%A2%E8%BD%A6%E7%89%8C/" rel="tag">换车牌</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%8E%92%E5%BA%8F/" rel="tag">排序</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%8E%A5%E9%9B%A8%E6%B0%B4/" rel="tag">接雨水</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%95%B0%E6%8D%AE%E6%BA%90%E5%8A%A8%E6%80%81%E5%88%87%E6%8D%A2/" rel="tag">数据源动态切换</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84/" rel="tag">数据结构</a><span class="tag-list-count">11</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%96%B0%E8%AF%AD%E8%A8%80/" rel="tag">新语言</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%97%85%E6%B8%B8/" rel="tag">旅游</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%97%A5%E5%BF%97/" rel="tag">日志</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%9B%BE%E5%8E%9D%E5%9E%B5/" rel="tag">曾厝垵</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%9C%80%E5%B0%8F%E6%A0%88/" rel="tag">最小栈</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%9D%80%E4%BA%BA%E8%AF%9B%E5%BF%83/" rel="tag">杀人诛心</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%9D%AD%E5%B7%9E/" rel="tag">杭州</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%A0%87%E8%AE%B0%E6%95%B4%E7%90%86/" rel="tag">标记整理</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%A4%8D%E7%89%A9%E5%9B%AD/" rel="tag">植物园</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%B2%99%E8%8C%B6%E9%9D%A2/" rel="tag">沙茶面</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%B3%A8%E8%A7%A3/" rel="tag">注解</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%B5%B7%E8%9B%8E%E7%85%8E/" rel="tag">海蛎煎</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%B6%88%E6%81%AF%E9%98%9F%E5%88%97/" rel="tag">消息队列</a><span class="tag-list-count">9</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%B7%98%E6%B1%B0%E7%AD%96%E7%95%A5/" rel="tag">淘汰策略</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%BA%90%E7%A0%81/" rel="tag">源码</a><span class="tag-list-count">11</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E6%BA%90%E7%A0%81%E8%A7%A3%E6%9E%90/" rel="tag">源码解析</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%94%9F%E6%B4%BB/" rel="tag">生活</a><span class="tag-list-count">40</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%94%B5%E7%93%B6%E8%BD%A6/" rel="tag">电瓶车</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%96%AB%E6%83%85/" rel="tag">疫情</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%9C%8B%E4%B9%A6/" rel="tag">看书</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%9C%8B%E5%89%A7/" rel="tag">看剧</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%9F%A9%E9%98%B5/" rel="tag">矩阵</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%AB%AF%E5%8F%A3%E8%BD%AC%E5%8F%91/" rel="tag">端口转发</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%B1%BB%E5%8A%A0%E8%BD%BD/" rel="tag">类加载</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%B3%9F%E5%BF%83%E4%BA%8B/" rel="tag">糟心事</a><span class="tag-list-count">5</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%B4%A2%E5%BC%95/" rel="tag">索引</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BA%BF%E7%A8%8B%E6%B1%A0/" rel="tag">线程池</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BC%93%E5%AD%98/" rel="tag">缓存</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BC%93%E5%AD%98%E5%87%BB%E7%A9%BF/" rel="tag">缓存击穿</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BC%93%E5%AD%98%E7%A9%BF%E9%80%8F/" rel="tag">缓存穿透</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BC%93%E5%AD%98%E9%9B%AA%E5%B4%A9/" rel="tag">缓存雪崩</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BC%96%E7%A0%81/" rel="tag">编码</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E7%BE%8E%E5%9B%BD/" rel="tag">美国</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%80%81%E7%94%B5%E8%84%91/" rel="tag">老电脑</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%87%AA%E5%8A%A8%E8%A3%85%E9%85%8D/" rel="tag">自动装配</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%87%AA%E6%97%8B/" rel="tag">自旋</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%87%AA%E9%80%82%E5%BA%94%E6%8B%93%E5%B1%95/" rel="tag">自适应拓展</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%A3%85%E7%94%B5%E8%84%91/" rel="tag">装电脑</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%A7%84%E5%88%99/" rel="tag">规则</a><span class="tag-list-count">4</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%A7%A3%E6%9E%90/" rel="tag">解析</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%AE%BE%E8%AE%A1%E6%A8%A1%E5%BC%8F/" rel="tag">设计模式</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%AF%BB%E4%B9%A6/" rel="tag">读书</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%AF%BB%E5%90%8E%E6%84%9F/" rel="tag">读后感</a><span class="tag-list-count">3</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%B4%9F%E8%BD%BD%E5%9D%87%E8%A1%A1/" rel="tag">负载均衡</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%B6%B3%E7%90%83/" rel="tag">足球</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%B7%91%E6%AD%A5/" rel="tag">跑步</a><span class="tag-list-count">6</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%B7%AF%E6%94%BF%E8%A7%84%E5%88%92/" rel="tag">路政规划</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%B7%B3%E6%B0%B4/" rel="tag">跳水</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%B8%A9%E8%B8%8F/" rel="tag">踩踏</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%BD%AC%E4%B9%89/" rel="tag">转义</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%BD%BB%E9%87%8F%E7%BA%A7%E9%94%81/" rel="tag">轻量级锁</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%BF%87%E6%9C%9F%E7%AD%96%E7%95%A5/" rel="tag">过期策略</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%BF%90%E5%8A%A8/" rel="tag">运动</a><span class="tag-list-count">8</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E8%BF%9C%E7%A8%8B%E5%8A%9E%E5%85%AC/" rel="tag">远程办公</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%80%92%E5%BD%92/" rel="tag">递归</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%87%8D%E9%87%8F%E7%BA%A7%E9%94%81/" rel="tag">重量级锁</a><span class="tag-list-count">2</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%93%BE%E6%8E%A5/" rel="tag">链接</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%A2%98%E8%A7%A3/" rel="tag">题解</a><span class="tag-list-count">24</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%A9%AC%E6%88%8F%E5%9B%A2/" rel="tag">马戏团</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%AA%8C%E8%AF%81/" rel="tag">验证</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%AA%91%E8%BD%A6/" rel="tag">骑车</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%AB%98%E9%80%9F/" rel="tag">高速</a><span class="tag-list-count">1</span></li><li class="tag-list-item"><a class="tag-list-link" href="/tags/%E9%BC%93%E6%B5%AA%E5%B1%BF/" rel="tag">鼓浪屿</a><span class="tag-list-count">1</span></li></ul></canvas></div></div><div class="links-of-blogroll site-overview-item animated"><div class="links-of-blogroll-title"><i class="fa fa-globe fa-fw"></i> Links</div><ul class="links-of-blogroll-list"><li class="links-of-blogroll-item"><a href="https://covermusic.cn/" title="https:&#x2F;&#x2F;covermusic.cn" rel="noopener" target="_blank">69伙伴</a></li></ul></div></div></div></div></aside><div class="sidebar-dimmer"></div></header><div class="back-to-top" role="button" aria-label="返回顶部"><i class="fa fa-arrow-up"></i> <span>0%</span></div><a href="https://github.com/nicksxs" class="github-corner" title="Follow me on GitHub" aria-label="Follow me on GitHub" rel="noopener" target="_blank"><svg width="80" height="80" viewBox="0 0 250 250" aria-hidden="true"><path d="M0,0 L115,115 L130,115 L142,142 L250,250 L250,0 Z"></path><path d="M128.3,109.0 C113.8,99.7 119.0,89.6 119.0,89.6 C122.0,82.7 120.5,78.6 120.5,78.6 C119.2,72.0 123.4,76.3 123.4,76.3 C127.3,80.9 125.5,87.3 125.5,87.3 C122.9,97.6 130.6,101.9 134.4,103.2" fill="currentColor" style="transform-origin:130px 106px" class="octo-arm"></path><path d="M115.0,115.0 C114.9,115.1 118.7,116.5 119.8,115.4 L133.7,101.6 C136.9,99.2 139.9,98.4 142.2,98.6 C133.8,88.0 127.5,74.4 143.8,58.0 C148.5,53.4 154.0,51.2 159.7,51.0 C160.3,49.4 163.2,43.6 171.4,40.1 C171.4,40.1 176.1,42.5 178.8,56.2 C183.1,58.6 187.2,61.8 190.9,65.4 C194.5,69.0 197.7,73.2 200.1,77.6 C213.8,80.2 216.3,84.9 216.3,84.9 C212.7,93.1 206.9,96.0 205.4,96.6 C205.1,102.4 203.0,107.8 198.3,112.5 C181.9,128.9 168.3,122.5 157.7,114.1 C157.9,116.9 156.7,120.9 152.7,124.9 L141.0,136.5 C139.8,137.7 141.6,141.9 141.8,141.8 Z" fill="currentColor" class="octo-body"></path></svg></a><noscript><div class="noscript-warning">Theme NexT works best with JavaScript enabled</div></noscript><div class="main-inner post posts-expand"><div class="post-block"><article itemscope itemtype="http://schema.org/Article" class="post-content" lang="zh-CN"><link itemprop="mainEntityOfPage" href="https://nicksxs.me/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/"><span hidden itemprop="author" itemscope itemtype="http://schema.org/Person"><meta itemprop="image" content="/uploads/avatar.jpg"><meta itemprop="name" content="Nicksxs"></span><span hidden itemprop="publisher" itemscope itemtype="http://schema.org/Organization"><meta itemprop="name" content="Nicksxs's Blog"><meta itemprop="description" content="learn from zero,技术博客,Nicksxs,史学森"></span><span hidden itemprop="post" itemscope itemtype="http://schema.org/CreativeWork"><meta itemprop="name" content="聊聊 Sharding-Jdbc 分库分表下的分页方案 | Nicksxs's Blog"><meta itemprop="description" content=""></span><header class="post-header"><h1 class="post-title" itemprop="name headline">聊聊 Sharding-Jdbc 分库分表下的分页方案</h1><div class="post-meta-container"><div class="post-meta"><span class="post-meta-item"><span class="post-meta-item-icon"><i class="far fa-calendar"></i> </span><span class="post-meta-item-text">发表于</span> <time title="创建时间:2022-01-09 20:02:49" itemprop="dateCreated datePublished" datetime="2022-01-09T20:02:49+08:00">2022-01-09</time> </span><span class="post-meta-item"><span class="post-meta-item-icon"><i class="far fa-calendar-check"></i> </span><span class="post-meta-item-text">更新于</span> <time title="修改时间:2022-06-11 22:45:11" itemprop="dateModified" datetime="2022-06-11T22:45:11+08:00">2022-06-11</time> </span><span class="post-meta-item"><span class="post-meta-item-icon"><i class="far fa-folder"></i> </span><span class="post-meta-item-text">分类于</span> <span itemprop="about" itemscope itemtype="http://schema.org/Thing"><a href="/categories/Java/" itemprop="url" rel="index"><span itemprop="name">Java</span></a> </span></span><span id="/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/" class="post-meta-item leancloud_visitors" data-flag-title="聊聊 Sharding-Jdbc 分库分表下的分页方案" title="阅读次数"><span class="post-meta-item-icon"><i class="far fa-eye"></i> </span><span class="post-meta-item-text">阅读次数:</span> <span class="leancloud-visitors-count"></span> </span><span class="post-meta-item" title="阅读次数" id="busuanzi_container_page_pv"><span class="post-meta-item-icon"><i class="far fa-eye"></i> </span><span class="post-meta-item-text">阅读次数:</span> <span id="busuanzi_value_page_pv"></span> </span><span class="post-meta-item"><span class="post-meta-item-icon"><i class="far fa-comment"></i> </span><span class="post-meta-item-text">Disqus:</span> <a title="disqus" href="/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/#disqus_thread" itemprop="discussionUrl"><span class="post-comments-count disqus-comment-count" data-disqus-identifier="2022/01/09/聊聊-Sharding-Jdbc-分库分表下的分页方案/" itemprop="commentCount"></span></a></span></div></div></header><div class="post-body" itemprop="articleBody"><p>前面在聊 Sharding-Jdbc 的时候看到了一篇文章,关于一个分页的查询,一直比较直接的想法就是分库分表下的分页是非常不合理的,一般我们的实操方案都是分表加上 ES 搜索做分页,或者通过合表读写分离的方案,因为对于 sharding-jdbc 如果没有带分表键,查询基本都是只能在所有分表都执行一遍,然后再加上分页,基本上是分页越大后续的查询越耗资源,但是仔细的去想这个细节还是这次,就简单说说<br>首先就是我的分表结构</p><pre class="line-numbers language-sql" data-language="sql"><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> <span class="token identifier"><span class="token punctuation">`</span>student_time_0<span class="token punctuation">`</span></span> <span class="token punctuation">(</span>
<span class="token identifier"><span class="token punctuation">`</span>id<span class="token punctuation">`</span></span> <span class="token keyword">int</span><span class="token punctuation">(</span><span class="token number">11</span><span class="token punctuation">)</span> <span class="token keyword">unsigned</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span> <span class="token keyword">AUTO_INCREMENT</span><span class="token punctuation">,</span>
<span class="token identifier"><span class="token punctuation">`</span>user_id<span class="token punctuation">`</span></span> <span class="token keyword">int</span><span class="token punctuation">(</span><span class="token number">11</span><span class="token punctuation">)</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token identifier"><span class="token punctuation">`</span>name<span class="token punctuation">`</span></span> <span class="token keyword">varchar</span><span class="token punctuation">(</span><span class="token number">200</span><span class="token punctuation">)</span> <span class="token keyword">COLLATE</span> utf8_bin <span class="token keyword">DEFAULT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token identifier"><span class="token punctuation">`</span>age<span class="token punctuation">`</span></span> <span class="token keyword">tinyint</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">)</span> <span class="token keyword">unsigned</span> <span class="token keyword">DEFAULT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token identifier"><span class="token punctuation">`</span>create_time<span class="token punctuation">`</span></span> <span class="token keyword">bigint</span><span class="token punctuation">(</span><span class="token number">20</span><span class="token punctuation">)</span> <span class="token keyword">DEFAULT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span><span class="token identifier"><span class="token punctuation">`</span>id<span class="token punctuation">`</span></span><span class="token punctuation">)</span>
<span class="token punctuation">)</span> <span class="token keyword">ENGINE</span><span class="token operator">=</span><span class="token keyword">InnoDB</span> <span class="token keyword">AUTO_INCREMENT</span><span class="token operator">=</span><span class="token number">674</span> <span class="token keyword">DEFAULT</span> <span class="token keyword">CHARSET</span><span class="token operator">=</span>utf8 <span class="token keyword">COLLATE</span><span class="token operator">=</span>utf8_bin<span class="token punctuation">;</span><span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span></code></pre><p>有这样的三个表,<code>student_time_0</code>, <code>student_time_1</code>, <code>student_time_2</code>, 以 user_id 作为分表键,根据表数量取模作为分表依据<br>这里先构造点数据,</p><pre class="line-numbers language-sql" data-language="sql"><code class="language-sql"><span class="token keyword">insert</span> <span class="token keyword">into</span> student_time <span class="token punctuation">(</span><span class="token identifier"><span class="token punctuation">`</span>name<span class="token punctuation">`</span></span><span class="token punctuation">,</span> <span class="token identifier"><span class="token punctuation">`</span>user_id<span class="token punctuation">`</span></span><span class="token punctuation">,</span> <span class="token identifier"><span class="token punctuation">`</span>age<span class="token punctuation">`</span></span><span class="token punctuation">,</span> <span class="token identifier"><span class="token punctuation">`</span>create_time<span class="token punctuation">`</span></span><span class="token punctuation">)</span> <span class="token keyword">values</span> <span class="token punctuation">(</span>?<span class="token punctuation">,</span> ?<span class="token punctuation">,</span> ?<span class="token punctuation">,</span> ?<span class="token punctuation">)</span><span aria-hidden="true" class="line-numbers-rows"><span></span></span></code></pre><p>主要是为了保证 <code>create_time</code> 唯一比较好说明问题,</p><pre class="line-numbers language-java" data-language="java"><code class="language-java"><span class="token keyword">int</span> i <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span>
<span class="token keyword">try</span> <span class="token punctuation">(</span>
<span class="token class-name">Connection</span> conn <span class="token operator">=</span> dataSource<span class="token punctuation">.</span><span class="token function">getConnection</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">PreparedStatement</span> ps <span class="token operator">=</span> conn<span class="token punctuation">.</span><span class="token function">prepareStatement</span><span class="token punctuation">(</span>insertSql<span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">&#123;</span>
<span class="token keyword">do</span> <span class="token punctuation">&#123;</span>
ps<span class="token punctuation">.</span><span class="token function">setString</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> localName <span class="token operator">+</span> <span class="token keyword">new</span> <span class="token class-name">Random</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">nextInt</span><span class="token punctuation">(</span><span class="token number">100</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
ps<span class="token punctuation">.</span><span class="token function">setLong</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">,</span> <span class="token number">10086L</span> <span class="token operator">+</span> <span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Random</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">nextInt</span><span class="token punctuation">(</span><span class="token number">100</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
ps<span class="token punctuation">.</span><span class="token function">setInt</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">,</span> <span class="token number">18</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
ps<span class="token punctuation">.</span><span class="token function">setLong</span><span class="token punctuation">(</span><span class="token number">4</span><span class="token punctuation">,</span> <span class="token keyword">new</span> <span class="token class-name">Date</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">getTime</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">int</span> result <span class="token operator">=</span> ps<span class="token punctuation">.</span><span class="token function">executeUpdate</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token constant">LOGGER</span><span class="token punctuation">.</span><span class="token function">info</span><span class="token punctuation">(</span><span class="token string">"current execute result: &#123;&#125;"</span><span class="token punctuation">,</span> result<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token class-name">Thread</span><span class="token punctuation">.</span><span class="token function">sleep</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Random</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">nextInt</span><span class="token punctuation">(</span><span class="token number">100</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
i<span class="token operator">++</span><span class="token punctuation">;</span>
<span class="token punctuation">&#125;</span> <span class="token keyword">while</span> <span class="token punctuation">(</span>i <span class="token operator">&lt;=</span> <span class="token number">2000</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span></code></pre><p>三个表的数据分别是 673,678,650,说明符合预期了,各个表数据不一样,接下来比如我们想要做一个这样的分页查询</p><pre class="line-numbers language-sql" data-language="sql"><code class="language-sql"><span class="token keyword">select</span> <span class="token operator">*</span> <span class="token keyword">from</span> student_time <span class="token keyword">ORDER</span> <span class="token keyword">BY</span> create_time <span class="token keyword">ASC</span> <span class="token keyword">limit</span> <span class="token number">1000</span><span class="token punctuation">,</span> <span class="token number">5</span><span class="token punctuation">;</span><span aria-hidden="true" class="line-numbers-rows"><span></span></span></code></pre><p><code>student_time</code> 对于我们使用的 <code>sharding-jdbc</code> 来说当然是逻辑表,首先从一无所知去想这个查询如果我们自己来处理应该是怎么做,<br>首先是不是可以每个表都从 333 开始取 5 条数据,类似于下面的查询,然后进行 15 条的合并重排序获取前面的 5 条</p><pre class="line-numbers language-none"><code class="language-none">select * from student_time_0 ORDER BY create_time ASC limit 333, 5;
select * from student_time_1 ORDER BY create_time ASC limit 333, 5;
select * from student_time_2 ORDER BY create_time ASC limit 333, 5;<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span></span></code></pre><p>忽略前面 limit 差的 1,这个结果除非三个表的分布是绝对的均匀,否则结果肯定会出现一定的偏差,以为每个表的 333 这个位置对于其他表来说都不一定是一样的,这样对于最后整体的结果,就会出现偏差<br>因为一直在纠结怎么让这个更直观的表现出来,所以尝试画了个图<br><img data-src="https://img.nicksxs.com/uPic/Gj7TPq.png"><br>黑色的框代表我从每个表里按排序从 334 到 338 的 5 条数据, 他们在每个表里都是代表了各自正确的排序值,但是对于我们想要的其实是合表后的 1001,1005 这五条,然后我们假设总的排序值位于前 1000 的分布是第 0 个表是 320 条,第 1 个表是 340 条,第 2 个表是 340 条,那么可以明显地看出来我这么查的结果简单合并肯定是不对的。<br>那么 sharding-jdbc 是如何保证这个结果的呢,其实就是我在每个表里都查分页偏移量和分页大小那么多的数据,在我这个例子里就是对于 0,1,2 三个分表每个都查 1005 条数据,即使我的数据不平衡到最极端的情况,前 1005 条数据都出在某个分表中,也可以正确获得最后的结果,但是明显的问题就是大分页,数据较多,就会导致非常大的问题,即使如 sharding-jdbc 对于合并排序的优化做得比较好,也还是需要传输那么大量的数据,并且查询也耗时,那么有没有解决方案呢,应该说有两个,或者说主要是想讲后者<br>第一个办法是像这种查询,如果业务上不需要进行跳页,而是只给下一页,那么我们就能把前一次的最大偏移量的 create_time 记录下来,下一页就可以拿着这个偏移量进行查询,这个比较简单易懂,就不多说了<br>第二个办法是看的58 沈剑的一篇文章,尝试理解讲述一下,<br>这个办法的第一步跟前面那个错误的方法或者说不准确的方法一样,先是将分页偏移量平均后在三个表里进行查询</p><pre class="line-numbers language-none"><code class="language-none">t0
334 10158 nick95 18 1641548941767
335 10098 nick11 18 1641548941879
336 10167 nick51 18 1641548942089
337 10167 nick3 18 1641548942119
338 10170 nick57 18 1641548942169
t1
334 10105 nick98 18 1641548939071 最小
335 10174 nick94 18 1641548939377
336 10129 nick85 18 1641548939442
337 10141 nick84 18 1641548939480
338 10096 nick74 18 1641548939668
t2
334 10184 nick11 18 1641548945075
335 10109 nick93 18 1641548945382
336 10181 nick41 18 1641548945583
337 10130 nick80 18 1641548945993
338 10184 nick19 18 1641548946294 最大<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span></code></pre><p>然后要做什么呢,其实目标比较明白,因为前面那种方法其实就是我知道了前一页的偏移量,所以可以直接当做条件来进行查询,那这里我也想着拿到这个条件,所以我将第一遍查出来的最小的 create_time 和最大的 create_time 找出来,然后再去三个表里查询,其实主要是最小值,因为我拿着最小值去查以后我就能知道这个最小值在每个表里处在什么位置,</p><pre class="line-numbers language-none"><code class="language-none">t0
322 10161 nick81 18 1641548939284
323 10113 nick16 18 1641548939393
324 10110 nick56 18 1641548939577
325 10116 nick69 18 1641548939588
326 10173 nick51 18 1641548939646
t1
334 10105 nick98 18 1641548939071
335 10174 nick94 18 1641548939377
336 10129 nick85 18 1641548939442
337 10141 nick84 18 1641548939480
338 10096 nick74 18 1641548939668
t2
297 10136 nick28 18 1641548939161
298 10142 nick68 18 1641548939177
299 10124 nick41 18 1641548939237
300 10148 nick87 18 1641548939510
301 10169 nick23 18 1641548939715<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span></code></pre><p>我只贴了前五条数据,为了方便知道偏移量,每个分表都使用了自增主键,我们可以看到前一次查询的最小值分别在其他两个表里的位置分别是 322-1 和 297-1,那么对于总体来说这个时间应该是在 <code>322 - 1 + 333 + 297 - 1 = 951</code>,那这样子我只要对后面的数据最多每个表查 <code>1000 - 951 + 5 = 54</code> 条数据再进行合并排序就可以获得最终正确的结果。<br>这个就是传说中的二次查询法。</p></div><footer class="post-footer"><div class="reward-container"><div>Buy me a coffee</div><button>赞赏</button><div class="post-reward"><div><img src="https://i.loli.net/2020/01/12/NUlWanT31E8LQGx.png" alt="Nicksxs 微信"> <span>微信</span></div><div><img src="https://ooo.0o0.ooo/2016/08/17/57b421e773057.jpg" alt="Nicksxs 支付宝"> <span>支付宝</span></div></div></div><div class="post-copyright"><ul><li class="post-copyright-author"><strong>本文作者: </strong>Nicksxs</li><li class="post-copyright-link"><strong>本文链接:</strong> <a href="https://nicksxs.me/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/" title="聊聊 Sharding-Jdbc 分库分表下的分页方案">https://nicksxs.me/2022/01/09/聊聊-Sharding-Jdbc-分库分表下的分页方案/</a></li><li class="post-copyright-license"><strong>版权声明: </strong>本博客所有文章除特别声明外,均采用 <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="noopener" target="_blank"><i class="fab fa-fw fa-creative-commons"></i>BY-NC-SA</a> 许可协议。转载请注明出处!</li></ul></div><div class="post-tags"><a href="/tags/Java/" rel="tag"># Java</a> <a href="/tags/Sharding-Jdbc/" rel="tag"># Sharding-Jdbc</a></div><div class="post-nav"><div class="post-nav-item"><a href="/2021/12/31/%E8%81%8A%E8%81%8A%E6%9C%80%E8%BF%91%E5%B9%B3%E6%B7%A1%E7%9A%84%E7%94%9F%E6%B4%BB%E4%B9%8B%E3%80%8A%E8%8A%B1%E6%9D%9F%E8%88%AC%E7%9A%84%E6%81%8B%E7%88%B1%E3%80%8B%E8%A7%82%E5%90%8E%E6%84%9F/" rel="prev" title="聊聊最近平淡的生活之《花束般的恋爱》观后感"><i class="fa fa-chevron-left"></i> 聊聊最近平淡的生活之《花束般的恋爱》观后感</a></div><div class="post-nav-item"><a href="/2022/01/16/%E6%90%AC%E8%BF%90%E4%B8%A4%E4%B8%AA-StackOverflow-%E4%B8%8A%E7%9A%84-Mysql-%E7%BC%96%E7%A0%81%E7%9B%B8%E5%85%B3%E7%9A%84%E9%97%AE%E9%A2%98%E8%A7%A3%E7%AD%94/" rel="next" title="搬运两个 StackOverflow 上的 Mysql 编码相关的问题解答">搬运两个 StackOverflow 上的 Mysql 编码相关的问题解答 <i class="fa fa-chevron-right"></i></a></div></div></footer></article></div><div class="comments" id="disqus_thread"><noscript>Please enable JavaScript to view the comments powered by Disqus.</noscript></div></div></main><footer class="footer"><div class="footer-inner"><div class="beian"><a href="https://beian.miit.gov.cn/" rel="noopener" target="_blank">浙ICP备16002580号-2 </a><img src="/uploads/beian.png" alt=""><a href="http://www.beian.gov.cn/portal/registerSystemInfo?recordcode=33010602011094" rel="noopener" target="_blank">浙公网安备 33010602011094号</a></div><div class="copyright">&copy; <span itemprop="copyrightYear">2022</span> <span class="with-love"><i class="fa fa-heart"></i> </span><span class="author" itemprop="copyrightHolder">Nicksxs</span></div><div class="busuanzi-count"><span class="post-meta-item" id="busuanzi_container_site_uv"><span class="post-meta-item-icon"><i class="fa fa-user"></i> </span><span class="site-uv" title="总访客量"><span id="busuanzi_value_site_uv"></span> </span></span><span class="post-meta-item" id="busuanzi_container_site_pv"><span class="post-meta-item-icon"><i class="fa fa-eye"></i> </span><span class="site-pv" title="总访问量"><span id="busuanzi_value_site_pv"></span></span></span></div></div></footer><script src="https://cdnjs.cloudflare.com/ajax/libs/animejs/3.2.1/anime.min.js" integrity="sha256-XL2inqUJaslATFnHdJOi9GfQ60on8Wx1C2H8DYiN1xY=" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.0/jquery.min.js" integrity="sha256-/xUj+3OJU5yExlq6GSYGSHk7tPXikynS7ogEvDej/m4=" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/fancybox/3.5.7/jquery.fancybox.min.js" integrity="sha256-yt2kYMy0w8AbtF89WXb2P1rfjcP/HTHLT7097U8Y5b8=" crossorigin="anonymous"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/lozad.js/1.16.0/lozad.min.js" integrity="sha256-mOFREFhqmHeQbXpK2lp4nA3qooVgACfh88fpJftLBbc=" crossorigin="anonymous"></script><script src="/js/comments.js"></script><script src="/js/utils.js"></script><script src="/js/next-boot.js"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/hexo-generator-searchdb/1.4.0/search.js" integrity="sha256-vXZMYLEqsROAXkEw93GGIvaB2ab+QW6w3+1ahD9nXXA=" crossorigin="anonymous"></script><script src="/js/third-party/search/local-search.js"></script><script src="/js/third-party/fancybox.js"></script><script async src="https://busuanzi.ibruce.info/busuanzi/2.3/busuanzi.pure.mini.js"></script><script class="next-config" data-name="leancloud_visitors" type="application/json">{"enable":true,"app_id":"ysza182Vghlqjdt7QiwGLLJy-gzGzoHsz","app_key":"s9GDqbn7gnGGkusf66YRVccw","server_url":"https://leancloud.cn","security":true}</script><script src="/js/third-party/statistics/lean-analytics.js"></script><script src="https://cdnjs.cloudflare.com/ajax/libs/quicklink/2.2.0/quicklink.umd.js" integrity="sha256-4kQf9z5ntdQrzsBC3YSHnEz02Z9C1UeW/E9OgnvlzSY=" crossorigin="anonymous"></script><script class="next-config" data-name="quicklink" type="application/json">{"enable":true,"home":false,"archive":false,"delay":true,"timeout":3000,"priority":true,"url":"https://nicksxs.me/2022/01/09/%E8%81%8A%E8%81%8A-Sharding-Jdbc-%E5%88%86%E5%BA%93%E5%88%86%E8%A1%A8%E4%B8%8B%E7%9A%84%E5%88%86%E9%A1%B5%E6%96%B9%E6%A1%88/"}</script><script src="/js/third-party/quicklink.js"></script><script class="next-config" data-name="disqus" type="application/json">{"enable":true,"shortname":"nicksxs","count":true,"i18n":{"disqus":"disqus"}}</script><script src="/js/third-party/comments/disqus.js"></script></body></html>