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id="go-tianli-blog">前往爱发电购买</div></div><script data-pjax src="/js/anzhiyu/ai_abstract.js"></script></div><article class="post-content" id="article-container" itemscope itemtype="https://ctext.top/4c2a.html"><header><a class="post-meta-categories" href="/categories/%E6%8A%80%E6%9C%AF%E6%95%99%E7%A8%8B/" itemprop="url">技术教程</a><a href="/tags/MYSQL/" tabindex="-1" itemprop="url">MYSQL</a><h1 id="CrawlerTitle" itemprop="name headline">索引下推</h1><span itemprop="author" itemscope itemtype="http://schema.org/Person">伴随</span><time itemprop="dateCreated datePublished" datetime="2025-01-02T08:21:35.000Z" title="发表于 2025-01-02 16:21:35">2025-01-02</time><time itemprop="dateCreated datePublished" datetime="2025-01-02T12:21:35.000Z" title="更新于 2025-01-02 20:21:35">2025-01-02</time></header><h1>什么是索引下推？(index condition pushdown)</h1>
<p>索引下推是MySQL中的一种查询优化技术，主要用于提高查询效率。它允许MySQL在存储引擎层使用索引来过滤数据，而不是将所有数据从存储引擎传输到服务器层 后再进行过滤。这样可以减少不必要的数据传输，从而提高查询性能。</p>
<h2 id="前期准备">前期准备</h2>
<ul>
<li>创建表</li>
</ul>
<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">CREATE</span> <span class="keyword">TABLE</span> orders (</span><br><span class="line"> id <span class="type">INT</span> <span class="keyword">PRIMARY</span> KEY, <span class="comment">-- 主键索引</span></span><br><span class="line"> user_id <span class="type">INT</span>, <span class="comment">-- 用户ID</span></span><br><span class="line"> status <span class="type">VARCHAR</span>(<span class="number">10</span>), <span class="comment">-- 订单状态</span></span><br><span class="line"> created_at DATETIME, <span class="comment">-- 创建时间</span></span><br><span class="line"> amount <span class="type">DECIMAL</span>(<span class="number">10</span>,<span class="number">2</span>), <span class="comment">-- 订单金额</span></span><br><span class="line"> INDEX idx_orders (user_id, status, created_at) <span class="comment">-- 联合索引</span></span><br><span class="line">);</span><br></pre></td></tr></table></figure>
<ul>
<li>查询语句</li>
</ul>
<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">SELECT</span> <span class="operator">*</span> <span class="keyword">FROM</span> orders </span><br><span class="line"><span class="keyword">WHERE</span> user_id <span class="operator">=</span> <span class="number">100</span> <span class="keyword">AND</span> status <span class="operator">=</span> <span class="string">'shipped'</span> <span class="keyword">AND</span> created_at <span class="operator">></span> <span class="string">'2024-01-01'</span>;</span><br></pre></td></tr></table></figure>
<h2 id="SQL的执行逻辑">SQL的执行逻辑</h2>
<p>MySQL底层一共分为四层</p>
<ul>
<li>连接层（Client Connectors）：负责客户端与 MySQL 的通信（如 TCP/IP、Socket 等），处理连接、认证、权限校验等。</li>
<li>服务层（Server Layer）：解析 SQL、优化执行计划、调用存储引擎接口。</li>
<li>存储引擎层（Storage Engine Layer）：负责数据的存储和检索，支持插件式引擎（如 InnoDB、MyISAM）。</li>
<li>文件系统层（File System）：存储数据文件（.ibd、.frm）、日志文件（redo log、binlog）等物理文件。</li>
</ul>
<figure class="highlight plaintext"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br></pre></td><td class="code"><pre><span class="line">客户端</span><br><span class="line"> │</span><br><span class="line"> ↓ 建立连接、发送 SQL</span><br><span class="line">连接层（认证、权限校验、连接池管理）</span><br><span class="line"> │</span><br><span class="line"> ↓ 传递 SQL</span><br><span class="line">服务层（解析器 → 优化器 → 执行器）</span><br><span class="line"> │</span><br><span class="line"> ↓ 调用存储引擎接口</span><br><span class="line">存储引擎层（InnoDB/MyISAM 读写数据）（回表）</span><br><span class="line"> │</span><br><span class="line"> ↓ 操作磁盘文件</span><br><span class="line">文件系统层（.ibd/.frm 文件、日志文件）</span><br><span class="line"> │</span><br><span class="line"> ↑ 返回数据</span><br><span class="line">存储引擎层 → 服务层 → 连接层 → 客户端</span><br></pre></td></tr></table></figure>
<p>MySQL 的查询执行过程可以分为 <mark class="hl-label green">解析、优化、执行</mark> 三个阶段。我们主要关注 执行阶段，并结合 索引下推 进行分析。</p>
<h3 id="1-判断索引的使用">1. 判断索引的使用</h3>
<p>MySQL 需要决定使用哪个索引，这里 WHERE 条件涉及 (user_id, status, created_at) 这三个列，而 idx_orders 这个索引正好覆盖了 user_id、status 和 created_at，所以 会使用该索引。</p>
<ul>
<li>索引匹配规则（最左前缀匹配）：</li>
</ul>
<blockquote>
<p>user_id = 100 可用索引 ✅<br>
status = ‘shipped’ 可用索引 ✅<br>
created_at > ‘2024-01-01’ 也可用索引（但范围查询会影响索引使用）</p>
</blockquote>
<p>因此，MySQL 选择 idx_orders 索引，并按以下步骤执行。</p>
<h3 id="2-具体执行步骤">2. 具体执行步骤</h3>
<ul>
<li>
<p>步骤 1：索引扫描</p>
<ul>
<li>MySQL 先利用 B+树索引，找到 user_id = 100 的数据范围。</li>
<li>然后在这个范围内，再筛选 status = ‘shipped’ 的记录。</li>
<li>如果<mark class="hl-label red">没有索引下推</mark> ，此时 MySQL 只会基于 user_id 和 status 进行索引扫描，找到符合条件的行，但 created_at > ‘2024-01-01’ 这个条件会在<mark class="hl-label red">回表后</mark> 再筛选。</li>
</ul>
</li>
<li>
<p>步骤 2：<mark class="hl-label orange">索引下推（如果启用）</mark> </p>
<ul>
<li>如果 MySQL 启用了索引下推（ICP），它会在索引扫描阶段就应用 created_at > ‘2024-01-01’ 的过滤条件</li>
<li>只有满足 user_id = 100、status = ‘shipped’ 且 created_at > ‘2024-01-01’ 的行会进入下一步，避免了不必要的回表操作。</li>
</ul>
</li>
<li>
<p>步骤 3：回表（如果需要）: <em>回表指的是如果索引列不完全包含所查询的字段，就需要回表，补全查询字段，然后返回</em></p>
<ul>
<li>由于 SELECT * 需要查询所有列（而索引 idx_orders 只包含 (user_id, status, created_at)），所以 MySQL 需要通过 主键回表 查询完整的行数据。</li>
<li>但 索引下推减少了不必要的回表，只对满足所有索引列筛选条件的行执行回表，从而提高了查询效率。</li>
</ul>
</li>
<li>
<p>步骤 4：返回数据</p>
<ul>
<li>读取回表数据后，MySQL 生成最终的结果集并返回给客户端。</li>
</ul>
</li>
</ul>
<h2 id="总结"><code>总结*</code></h2>
<h3 id="索引下推发生的条件">索引下推发生的条件</h3>
<ul>
<li>使用了<mark class="hl-label blue">二级索引</mark> （非主键索引）</li>
<li>查询条件涉及<mark class="hl-label blue">索引列</mark> </li>
<li>查询的字段<mark class="hl-label blue">不完全包含在索引中</mark> （可能回表）
<ul>
<li>如果查询字段包含在索引中，是否使用索引下推执行效率都是一样的，因为不需要回表</li>
</ul>
</li>
<li>索引列的筛选条件是<mark class="hl-label blue">范围查询</mark> (>, <, BETWEEN) 或 LIKE ‘xxx%’</li>
<li>数据库版本大于等于5.7</li>
</ul>
<h3 id="如何判断是否使用索引下推">如何判断是否使用索引下推</h3>
<p>使用EXPLAIN查询分析计划，查看Extra列，如果包含<code>Using index condition</code>说明使用了索引下推</p>
<h3 id="开关索引下推">开关索引下推</h3>
<figure class="highlight sql"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">-- 查询</span></span><br><span class="line"><span class="keyword">SHOW</span> VARIABLES <span class="keyword">LIKE</span> <span class="string">'optimizer_switch'</span>;</span><br><span class="line"></span><br><span class="line"><span class="comment">-- 开（全局）</span></span><br><span class="line"><span class="keyword">SET</span> <span class="keyword">GLOBAL</span> optimizer_switch <span class="operator">=</span> <span class="string">'index_condition_pushdown=on'</span>;</span><br><span class="line"></span><br><span class="line"><span class="comment">-- 关（全局）</span></span><br><span class="line"><span class="keyword">SET</span> <span class="keyword">GLOBAL</span> optimizer_switch <span class="operator">=</span> <span class="string">'index_condition_pushdown=off'</span>;</span><br></pre></td></tr></table></figure>
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class="toc-number">1.2.</span> <span class="toc-text">SQL的执行逻辑</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#1-%E5%88%A4%E6%96%AD%E7%B4%A2%E5%BC%95%E7%9A%84%E4%BD%BF%E7%94%A8"><span class="toc-number">1.2.1.</span> <span class="toc-text">1. 判断索引的使用</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#2-%E5%85%B7%E4%BD%93%E6%89%A7%E8%A1%8C%E6%AD%A5%E9%AA%A4"><span class="toc-number">1.2.2.</span> <span class="toc-text">2. 具体执行步骤</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E6%80%BB%E7%BB%93"><span class="toc-number">1.3.</span> <span class="toc-text">总结*</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E7%B4%A2%E5%BC%95%E4%B8%8B%E6%8E%A8%E5%8F%91%E7%94%9F%E7%9A%84%E6%9D%A1%E4%BB%B6"><span class="toc-number">1.3.1.</span> <span class="toc-text">索引下推发生的条件</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#%E5%A6%82%E4%BD%95%E5%88%A4%E6%96%AD%E6%98%AF%E5%90%A6%E4%BD%BF%E7%94%A8%E7%B4%A2%E5%BC%95%E4%B8%8B%E6%8E%A8"><span class="toc-number">1.3.2.</span> <span class="toc-text">如何判断是否使用索引下推</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#%E5%BC%80%E5%85%B3%E7%B4%A2%E5%BC%95%E4%B8%8B%E6%8E%A8"><span class="toc-number">1.3.3.</span> <span class="toc-text">开关索引下推</span></a></li></ol></li></ol></li></ol></div></div><div class="card-widget card-recent-post"><div class="item-headline"><i class="anzhiyufont anzhiyu-icon-history"></i><span>最近发布</span></div><div class="aside-list"><div class="aside-list-item"><a class="thumbnail" href="/9b1f.html" title="WIN MAC 快捷键大全"><img src= "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" onerror="this.onerror=null,this.src="https://up.ctext.top/default_bg.png"" data-lazy-src="https://up.ctext.top/article/2025/02/quickKeys.png" 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getScript('https://cdn.cbd.int/pangu@4.0.7/dist/browser/pangu.min.js')
.then(() => {
pangu.autoSpacingPage()
})
}
}
function panguInit () {
if (false){
GLOBAL_CONFIG_SITE.isPost && panguFn()
} else {
panguFn()
}
}
document.addEventListener('DOMContentLoaded', panguInit)</script><canvas id="universe"></canvas><script async src="https://npm.elemecdn.com/anzhiyu-theme-static@1.0.0/dark/dark.js"></script><script async src="/anzhiyu/random.js"></script><script async="async">(function () {
var grt = new Date("01/02/2024 00:00:00"); //设置网站上线时间
var now = new Date();
var dnum;
var hnum;
var mnum;
var snum;
var nowHour;
// 计算并更新天数、小时数、分钟数和秒数
function updateTime() {
now = new Date(); // 更新 now 的值
nowHour = now.getHours(); // 更新 nowHour 的值
var days = (now - grt) / 1000 / 60 / 60 / 24;
dnum = Math.floor(days);
var hours = (now - grt) / 1000 / 60 / 60 - 24 * dnum;
hnum = Math.floor(hours);
if (String(hnum).length == 1) {
hnum = "0" + hnum;
}
var minutes = (now - grt) / 1000 / 60 - 24 * 60 * dnum - 60 * hnum;
mnum = Math.floor(minutes);
if (String(mnum).length == 1) {
mnum = "0" + mnum;
}
var seconds = (now - grt) / 1000 - 24 * 60 * 60 * dnum - 60 * 60 * hnum - 60 * mnum;
snum = Math.round(seconds);
if (String(snum).length == 1) {
snum = "0" + snum;
}
}
// 更新网页中显示的网站运行时间
function updateHtml() {
const footer = document.getElementById("footer");
if (!footer) return
let currentTimeHtml = "";
if (nowHour < 18 && nowHour >= 9) {
// 如果是上班时间，默认就是"安知鱼-上班摸鱼中.svg"图片，不需要更改
currentTimeHtml = `本站居然运行了 ${dnum} 天<span id='runtime'> ${hnum} 小时 ${mnum} 分 ${snum} 秒 </span><i class='anzhiyufont anzhiyu-icon-heartbeat' style='color:red'></i>`;
} else {
// 如果是下班时间，插入"安知鱼-下班啦.svg"图片
let img = document.querySelector("#workboard .workSituationImg");
if (img != null) {
img.src = "https://up.ctext.top/happy.svg";
img.title = "下班了就该开开心心的玩耍，嘿嘿~";
img.alt = "下班了就该开开心心的玩耍，嘿嘿~";
}
currentTimeHtml = `本站居然运行了 ${dnum} 天<span id='runtime'> ${hnum} 小时 ${mnum} 分 ${snum} 秒 </span><i class='anzhiyufont anzhiyu-icon-heartbeat' style='color:red'></i>`;
}
if (document.getElementById("runtimeTextTip")) {
document.getElementById("runtimeTextTip").innerHTML = currentTimeHtml;
}
}
setInterval(() => {
updateTime();
updateHtml();
}, 1000);
})();</script><script src="/js/search/local-search.js"></script><div class="js-pjax"><script>(() => {
const locale = {
nick: '你的专属昵称',
nickError: '昵称太短啦！至少得有3个字符才能算数哦！',
mail: '你的电子小信箱',
mailError: '哎呀，这不是一个合格的邮箱地址哦，请再检查一遍！',
link: '你有个酷酷的网址吗？',
optional: '这个嘛，想填就填，不填也行！',
placeholder: '吐槽一下？',
sofa: '来，坐沙发上，发表你的评论吧！',
submit: '一键发送，让世界听到你的声音！',
like: '点个赞，让TA知道你的心意！',
cancelLike: '哎呀，不小心点错了，取消赞！',
reply: '回复TA，开启一场对话吧！',
cancelReply: '等等，我话还没说完，取消回复！',
comment: '来，说说你的看法，让评论区热闹起来！',
refresh: '刷新一下，看看有啥新动态！',
more: '哇塞，还有更多精彩内容等你来加载！',
preview: '先睹为快，预览一下你的大作吧！',
emoji: '来，加点表情，让你的评论更生动！',
uploadImage: '上传你的美照，让大家一起欣赏！',
seconds: '刚刚才发的，新鲜出炉！',
minutes: '几分钟前，还热乎着呢！',
hours: '几小时前，热度还在哦！',
days: '几天前，但依旧值得一看！',
now: '哇塞，刚刚发的，快抢沙发！',
uploading: '稍等片刻，你的图片正在飞奔而来！',
login: '登录一下，解锁更多功能！',
logout: '拜拜了您嘞，下次再见！',
admin: '博主大人在此，谁敢造次！',
sticky: '置顶一下，让更多人看到你的精彩内容！',
word: '字',
wordHint: '评论字数要在0到1字之间哦！\n现在你已经写了$2个字了，加油！',
anonymous: '神秘人出没，猜猜是谁？',
level0: '潜水员，深藏不露！',
level1: '冒泡小能手，偶尔露个头！',
level2: '吐槽大师，一针见血！',
level3: '活跃分子，无处不在！',
level4: '话痨达人，说个不停！',
level5: '传说级大神，膜拜一下！',
gif: '动态表情包，让你的评论更有趣！',
gifSearchPlaceholder: '快来搜索你喜欢的表情包，让评论更生动！',
profile: '看看我的个人资料，了解一下我吧！',
approved: '审核通过，可以展示啦！',
waiting: '正在等待审核，别急哦！',
spam: '垃圾内容，走开走开！',
unsticky: '换个位置看看！',
oldest: '看看最早的评论！',
latest: '看看最新的动态！',
hottest: '看看哪条评论最火！',
reactionTitle: '快来对这篇文章发表你的看法吧，让博主知道你的想法！😜'
};
let initFn = window.walineFn || null
const initWaline = (Fn) => {
const waline = Fn(Object.assign({
el: '#waline-wrap',
serverURL: 'https://bc.ctext.top/',
pageview: false,
dark: 'html[data-theme="dark"]',
path: window.location.pathname,
comment: false,
imageUploader: true,
comment: false,
copyright: false,
reaction: true,
locale
}, null))
const destroyWaline = () => {
waline.destroy()
}
anzhiyu.addGlobalFn('pjax', destroyWaline, 'destroyWaline')
}
const loadWaline = async () => {
if (initFn) initWaline(initFn)
else {
await getCSS('https://cdn.cbd.int/@waline/client@3.1.3/dist/waline.css')
if (false) await getCSS('https://cdn.cbd.int/@waline/client@3.1.3/dist/waline-meta.css')
const { init } = await import('https://cdn.cbd.int/@waline/client@3.1.3/dist/waline.js')
initFn = init || Waline.init
initWaline(initFn)
window.walineFn = initFn
}
}
if ('Waline' === 'Waline' || !true) {
if (true) anzhiyu.loadComment(document.getElementById('waline-wrap'),loadWaline)
else setTimeout(loadWaline, 0)
} else {
window.loadOtherComment = loadWaline
}
})()</script><input type="hidden" name="page-type" id="page-type" value="post"></div><script>window.addEventListener('load', () => {
const changeContent = content => {
if (content === '') return content
content = content.replace(/<img.*?src="(.*?)"?[^\>]+>/ig, '[图片]') // replace image link
content = content.replace(/<a[^>]+?href=["']?([^"']+)["']?[^>]*>([^<]+)<\/a>/gi, '[链接]') // replace url
content = content.replace(/<pre><code>.*?<\/pre>/gi, '[代码]') // replace code
content = content.replace(/<[^>]+>/g,"") // remove html tag
if (content.length > 150) {
content = content.substring(0,150) + '...'
}
return content
}
const generateHtml = array => {
let result = ''
if (array.length) {
for (let i = 0; i < array.length; i++) {
result += '<div class=\'aside-list-item\'>'
if (true) {
const name = 'data-lazy-src'
result += `<a href='${array[i].url}' class='thumbnail'><img ${name}='${array[i].avatar}' alt='${array[i].nick}'></a>`
}
result += `<div class='content'>
<a class='comment' href='${array[i].url}' title='${array[i].content}'>${array[i].content}</a>
<div class='name'><span>${array[i].nick} / </span><time datetime="${array[i].date}">${anzhiyu.diffDate(array[i].date, true)}</time></div>
</div></div>`
}
} else {
result += '没有评论'
}
let $dom = document.querySelector('#card-newest-comments .aside-list')
$dom && ($dom.innerHTML= result)
window.lazyLoadInstance && window.lazyLoadInstance.update()
window.pjax && window.pjax.refresh($dom)
}
const getComment = async () => {
try {
const res = await fetch('https://bc.ctext.top/api/comment?type=recent&count=6', { method: 'GET' })
const result = await res.json()
const walineArray = result.data.map(e => {
return {
'content': changeContent(e.comment),
'avatar': e.avatar,
'nick': e.nick,
'url': e.url + '#' + e.objectId,
'date': e.time || e.insertedAt
}
})
saveToLocal.set('waline-newest-comments', JSON.stringify(walineArray), 10/(60*24))
generateHtml(walineArray)
} catch (err) {
console.error(err)
const $dom = document.querySelector('#card-newest-comments .aside-list')
$dom.textContent= "无法获取评论，请确认相关配置是否正确"
}
}
const newestCommentInit = () => {
if (document.querySelector('#card-newest-comments .aside-list')) {
const data = saveToLocal.get('waline-newest-comments')
if (data) {
generateHtml(JSON.parse(data))
} else {
getComment()
}
}
}
newestCommentInit()
document.addEventListener('pjax:complete', newestCommentInit)
})</script><script async data-pjax src="https://cdn.cbd.int/anzhiyu-theme-static@1.0.0/waterfall/waterfall.js"></script><script src="https://lf3-cdn-tos.bytecdntp.com/cdn/expire-1-M/qrcodejs/1.0.0/qrcode.min.js"></script><script src="/js/anzhiyu/right_click_menu.js"></script><link rel="stylesheet" href="https://cdn.cbd.int/anzhiyu-theme-static@1.1.9/icon/ali_iconfont_css.css"><script async src="https://at.alicdn.com/t/c/font_4489064_ow7l1rcvcw.js?spm=a313x.manage_type_myprojects.i1.12.61783a81xP1PqH&file=font_4489064_ow7l1rcvcw.js"></script><script async data-pjax src="/js/imgloaded.js?1"></script><script src="https://cdn.staticfile.org/jquery/3.6.3/jquery.min.js"></script><script defer="true" src="/js/welcome.js"></script><script defer="true" src="/js/hideRolling.js"></script><script defer="true" src="/js/countdown.js"></script><script defer src="https://cdn.jsdelivr.net/combine/npm/jquery@latest/dist/jquery.min.js,gh/weilining/jsdelivr/jquery/circlemagic/circlemagic.min.js,gh/weilining/jsdelivr@latest/jquery/circlemagic/butterflycirclemagic.js"></script><script id="canvas_nest" defer="defer" color="0,0,255" opacity="0.7" zIndex="-1" count="99" mobile="false" src="https://cdn.cbd.int/butterfly-extsrc@1.1.3/dist/canvas-nest.min.js"></script><script id="click-heart" src="https://cdn.cbd.int/butterfly-extsrc@1.1.3/dist/click-heart.min.js" async="async" mobile="false"></script><link rel="stylesheet" href="https://cdn.cbd.int/anzhiyu-theme-static@1.0.0/aplayer/APlayer.min.css" media="print" onload="this.media='all'"><script src="https://cdn.cbd.int/anzhiyu-blog-static@1.0.1/js/APlayer.min.js"></script><script src="https://cdn.cbd.int/hexo-anzhiyu-music@1.0.1/assets/js/Meting2.min.js"></script><script src="https://cdn.cbd.int/pjax@0.2.8/pjax.min.js"></script><script>let pjaxSelectors = ["head > title","#config-diff","#body-wrap","#rightside-config-hide","#rightside-config-show",".js-pjax"]
var pjax = new Pjax({
elements: 'a:not([target="_blank"])',
selectors: pjaxSelectors,
cacheBust: false,
analytics: false,
scrollRestoration: false
})
document.addEventListener('pjax:send', function () {
// removeEventListener scroll
anzhiyu.removeGlobalFnEvent('pjax')
anzhiyu.removeGlobalFnEvent('themeChange')
document.getElementById('rightside').classList.remove('rightside-show')
if (window.aplayers) {
for (let i = 0; i < window.aplayers.length; i++) {
if (!window.aplayers[i].options.fixed) {
window.aplayers[i].destroy()
}
}
}
typeof typed === 'object' && typed.destroy()
//reset readmode
const $bodyClassList = document.body.classList
$bodyClassList.contains('read-mode') && $bodyClassList.remove('read-mode')
})
document.addEventListener('pjax:complete', function () {
window.refreshFn()
document.querySelectorAll('script[data-pjax]').forEach(item => {
const newScript = document.createElement('script')
const content = item.text || item.textContent || item.innerHTML || ""
Array.from(item.attributes).forEach(attr => newScript.setAttribute(attr.name, attr.value))
newScript.appendChild(document.createTextNode(content))
item.parentNode.replaceChild(newScript, item)
})
GLOBAL_CONFIG.islazyload && window.lazyLoadInstance.update()
typeof panguInit === 'function' && panguInit()
// google analytics
typeof gtag === 'function' && gtag('config', '', {'page_path': window.location.pathname});
// baidu analytics
typeof _hmt === 'object' && _hmt.push(['_trackPageview',window.location.pathname]);
typeof loadMeting === 'function' && document.getElementsByClassName('aplayer').length && loadMeting()
// prismjs
typeof Prism === 'object' && Prism.highlightAll()
})
document.addEventListener('pjax:error', e => {
if (e.request.status === 404) {
pjax.loadUrl('/404.html')
}
})</script><script async data-pjax src="//busuanzi.ibruce.info/busuanzi/2.3/busuanzi.pure.mini.js"></script><script charset="UTF-8" src="https://cdn.cbd.int/anzhiyu-theme-static@1.1.5/accesskey/accesskey.js"></script></div><div id="popup-window"><div class="popup-window-title">通知</div><div class="popup-window-divider"></div><div class="popup-window-content"><div class="popup-tip">你好呀</div><div class="popup-link"><i class="anzhiyufont anzhiyu-icon-arrow-circle-right"></i></div></div></div><!-- hexo injector body_end start --><script async src="//at.alicdn.com/t/font_2032782_8d5kxvn09md.js"></script><!-- hexo injector body_end end --></body></html>