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end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">数据查询</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable active"><!----><span class="title">运算符和函数</span><span class="arrow down"></span></button><ul class="sidebar-links"><li><!--[--><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html" class="router-link-active router-link-exact-active nav-link active sidebar-link sidebar-page active" aria-label="概述"><!---->概述<!----></a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#运算符列表" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="运算符列表"><!---->运算符列表<!----></a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a 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router-link-exact-active nav-link sidebar-link heading" aria-label="运算符优先级"><!---->运算符优先级<!----></a><ul class="sidebar-sub-headers"></ul></li></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#内置函数列表" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="内置函数列表"><!---->内置函数列表<!----></a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#聚合函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="聚合函数"><!---->聚合函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#数学函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="数学函数"><!---->数学函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#比较函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="比较函数"><!---->比较函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#字符串处理函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="字符串处理函数"><!---->字符串处理函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#数据类型转换函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="数据类型转换函数"><!---->数据类型转换函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#常序列生成函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="常序列生成函数"><!---->常序列生成函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#选择函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="选择函数"><!---->选择函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#区间查询函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="区间查询函数"><!---->区间查询函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#趋势计算函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="趋势计算函数"><!---->趋势计算函数<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#采样函数" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="采样函数"><!---->采样函数<!----></a><ul class="sidebar-sub-headers"></ul></li></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#条件表达式" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="条件表达式"><!---->条件表达式<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#数据质量函数库" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="数据质量函数库"><!---->数据质量函数库<!----></a><ul class="sidebar-sub-headers"></ul></li></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/User-Defined-Function.html" class="nav-link sidebar-link sidebar-page" aria-label="用户自定义函数"><!---->用户自定义函数<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Aggregation.html" class="nav-link sidebar-link sidebar-page" aria-label="聚合函数"><!---->聚合函数<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Mathematical.html" class="nav-link sidebar-link sidebar-page" aria-label="算数运算符和函数"><!---->算数运算符和函数<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Comparison.html" class="nav-link sidebar-link sidebar-page" aria-label="比较运算符和函数"><!---->比较运算符和函数<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Logical.html" class="nav-link sidebar-link sidebar-page" aria-label="逻辑运算符"><!---->逻辑运算符<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/String.html" class="nav-link sidebar-link sidebar-page" aria-label="字符串处理"><!---->字符串处理<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Conversion.html" class="nav-link sidebar-link sidebar-page" aria-label="数据类型转换"><!---->数据类型转换<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Constant.html" class="nav-link sidebar-link sidebar-page" aria-label="常序列生成"><!---->常序列生成<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Selection.html" class="nav-link sidebar-link sidebar-page" aria-label="选择函数"><!---->选择函数<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Continuous-Interval.html" class="nav-link sidebar-link sidebar-page" aria-label="区间查询"><!---->区间查询<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Variation-Trend.html" class="nav-link sidebar-link sidebar-page" aria-label="趋势计算"><!---->趋势计算<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Sample.html" class="nav-link sidebar-link sidebar-page" aria-label="采样函数"><!---->采样函数<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Time-Series.html" class="nav-link sidebar-link sidebar-page" aria-label="时间序列处理"><!---->时间序列处理<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Lambda.html" class="nav-link sidebar-link sidebar-page" aria-label="Lambda 表达式"><!---->Lambda 表达式<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Conditional.html" class="nav-link sidebar-link sidebar-page" aria-label="条件表达式"><!---->条件表达式<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Data-Profiling.html" class="nav-link sidebar-link sidebar-page" aria-label="数据画像"><!---->数据画像<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Anomaly-Detection.html" class="nav-link sidebar-link sidebar-page" aria-label="异常检测"><!---->异常检测<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Data-Matching.html" class="nav-link sidebar-link sidebar-page" aria-label="数据匹配"><!---->数据匹配<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Frequency-Domain.html" class="nav-link sidebar-link sidebar-page" aria-label="频域分析"><!---->频域分析<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Data-Quality.html" class="nav-link sidebar-link sidebar-page" aria-label="数据质量"><!---->数据质量<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Data-Repairing.html" class="nav-link sidebar-link sidebar-page" aria-label="数据修复"><!---->数据修复<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Series-Discovery.html" class="nav-link sidebar-link sidebar-page" aria-label="序列发现"><!---->序列发现<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/zh/UserGuide/V1.2.x/Operators-Functions/Machine-Learning.html" class="nav-link sidebar-link sidebar-page" aria-label="机器学习"><!---->机器学习<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li></ul></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">触发器</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">监控告警</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">权限管理</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">运维工具</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">端云协同</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">系统集成</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">分布式</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">FAQ</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">参考</span><span class="arrow end"></span></button><!----></section></li></ul><!--[--><!----><!--]--></aside><!--[--><main class="page" id="main-content"><!--[--><!----><nav class="breadcrumb disable"></nav><div class="page-title"><h1><!---->运算符和函数</h1><div class="page-info"><!----><!----><!----><!----><span class="page-reading-time-info" aria-label="阅读时间"><svg xmlns="http://www.w3.org/2000/svg" class="icon timer-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="timer icon"><path d="M799.387 122.15c4.402-2.978 7.38-7.897 7.38-13.463v-1.165c0-8.933-7.38-16.312-16.312-16.312H256.33c-8.933 0-16.311 7.38-16.311 16.312v1.165c0 5.825 2.977 10.874 7.637 13.592 4.143 194.44 97.22 354.963 220.201 392.763-122.204 37.542-214.893 196.511-220.2 389.397-4.661 5.049-7.638 11.651-7.638 19.03v5.825h566.49v-5.825c0-7.379-2.849-13.981-7.509-18.9-5.049-193.016-97.867-351.985-220.2-389.527 123.24-37.67 216.446-198.453 220.588-392.892zM531.16 450.445v352.632c117.674 1.553 211.787 40.778 211.787 88.676H304.097c0-48.286 95.149-87.382 213.728-88.676V450.445c-93.077-3.107-167.901-81.297-167.901-177.093 0-8.803 6.99-15.793 15.793-15.793 8.803 0 15.794 6.99 15.794 15.793 0 80.261 63.69 145.635 142.01 145.635s142.011-65.374 142.011-145.635c0-8.803 6.99-15.793 15.794-15.793s15.793 6.99 15.793 15.793c0 95.019-73.789 172.82-165.96 177.093z"></path></svg><span>大约 12 分钟</span><meta property="timeRequired" content="PT12M"></span><!----><!----></div><hr></div><div class="toc-place-holder"><aside id="toc"><!--[--><!----><!--]--><div class="toc-header">此页内容<button class="print-button" title="打印"><svg xmlns="http://www.w3.org/2000/svg" class="icon print-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="print icon"><path d="M819.2 364.8h-44.8V128c0-17.067-14.933-32-32-32H281.6c-17.067 0-32 14.933-32 32v236.8h-44.8C145.067 364.8 96 413.867 96 473.6v192c0 59.733 49.067 108.8 108.8 108.8h44.8V896c0 17.067 14.933 32 32 32h460.8c17.067 0 32-14.933 32-32V774.4h44.8c59.733 0 108.8-49.067 108.8-108.8v-192c0-59.733-49.067-108.8-108.8-108.8zM313.6 160h396.8v204.8H313.6V160zm396.8 704H313.6V620.8h396.8V864zM864 665.6c0 25.6-19.2 44.8-44.8 44.8h-44.8V588.8c0-17.067-14.933-32-32-32H281.6c-17.067 0-32 14.933-32 32v121.6h-44.8c-25.6 0-44.8-19.2-44.8-44.8v-192c0-25.6 19.2-44.8 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toc-link level3">选择函数</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#区间查询函数" class="router-link-active router-link-exact-active toc-link level3">区间查询函数</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#趋势计算函数" class="router-link-active router-link-exact-active toc-link level3">趋势计算函数</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#采样函数" class="router-link-active router-link-exact-active toc-link level3">采样函数</a></li><!----><!--]--></ul><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#条件表达式" class="router-link-active router-link-exact-active toc-link level2">条件表达式</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/zh/UserGuide/V1.2.x/Operators-Functions/Overview.html#数据质量函数库" class="router-link-active router-link-exact-active toc-link level2">数据质量函数库</a></li><!----><!--]--></ul></div><!--[--><!----><!--]--></aside></div><!----><div class="theme-hope-content"><!--

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--><h1 id="运算符和函数" tabindex="-1"><a class="header-anchor" href="#运算符和函数" aria-hidden="true">#</a> 运算符和函数</h1><p>本章介绍 IoTDB 支持的运算符和函数。IoTDB 提供了丰富的内置运算符和函数来满足您的计算需求，同时支持通过<a href="/zh/UserGuide/V1.2.x/Operators-Functions/User-Defined-Function.html" class="">用户自定义函数</a>能力进行扩展。</p><p>可以使用 <code>SHOW FUNCTIONS</code> 显示所有可用函数的列表，包括内置函数和自定义函数。</p><p>关于运算符和函数在 SQL 中的行为，可以查看文档 <a href="/zh/UserGuide/V1.2.x/Query-Data/Select-Expression.html" class="">选择表达式</a>。</p><h2 id="运算符列表" tabindex="-1"><a class="header-anchor" href="#运算符列表" aria-hidden="true">#</a> 运算符列表</h2><h3 id="算数运算符" tabindex="-1"><a class="header-anchor" href="#算数运算符" aria-hidden="true">#</a> 算数运算符</h3><table><thead><tr><th>运算符</th><th>含义</th></tr></thead><tbody><tr><td><code>+</code></td><td>取正（单目）</td></tr><tr><td><code>-</code></td><td>取负（单目）</td></tr><tr><td><code>*</code></td><td>乘</td></tr><tr><td><code>/</code></td><td>除</td></tr><tr><td><code>%</code></td><td>取余</td></tr><tr><td><code>+</code></td><td>加</td></tr><tr><td><code>-</code></td><td>减</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Mathematical.html" class="">算数运算符和函数</a>。</p><h3 id="比较运算符" tabindex="-1"><a class="header-anchor" href="#比较运算符" aria-hidden="true">#</a> 比较运算符</h3><table><thead><tr><th>运算符</th><th>含义</th></tr></thead><tbody><tr><td><code>&gt;</code></td><td>大于</td></tr><tr><td><code>&gt;=</code></td><td>大于等于</td></tr><tr><td><code>&lt;</code></td><td>小于</td></tr><tr><td><code>&lt;=</code></td><td>小于等于</td></tr><tr><td><code>==</code></td><td>等于</td></tr><tr><td><code>!=</code> / <code>&lt;&gt;</code></td><td>不等于</td></tr><tr><td><code>BETWEEN ... AND ...</code></td><td>在指定范围内</td></tr><tr><td><code>NOT BETWEEN ... AND ...</code></td><td>不在指定范围内</td></tr><tr><td><code>LIKE</code></td><td>匹配简单模式</td></tr><tr><td><code>NOT LIKE</code></td><td>无法匹配简单模式</td></tr><tr><td><code>REGEXP</code></td><td>匹配正则表达式</td></tr><tr><td><code>NOT REGEXP</code></td><td>无法匹配正则表达式</td></tr><tr><td><code>IS NULL</code></td><td>是空值</td></tr><tr><td><code>IS NOT NULL</code></td><td>不是空值</td></tr><tr><td><code>IN</code> / <code>CONTAINS</code></td><td>是指定列表中的值</td></tr><tr><td><code>NOT IN</code> / <code>NOT CONTAINS</code></td><td>不是指定列表中的值</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Comparison.html" class="">比较运算符和函数</a>。</p><h3 id="逻辑运算符" tabindex="-1"><a class="header-anchor" href="#逻辑运算符" aria-hidden="true">#</a> 逻辑运算符</h3><table><thead><tr><th>运算符</th><th>含义</th></tr></thead><tbody><tr><td><code>NOT</code> / <code>!</code></td><td>取非（单目）</td></tr><tr><td><code>AND</code> / <code>&amp;</code> / <code>&amp;&amp;</code></td><td>逻辑与</td></tr><tr><td><code>OR</code>/ | / ||</td><td>逻辑或</td></tr></tbody></table><!--- &#124;即管道符 转义不能用在``里, 表格内不允许使用管道符 --><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Logical.html" class="">逻辑运算符</a>。</p><h3 id="运算符优先级" tabindex="-1"><a class="header-anchor" href="#运算符优先级" aria-hidden="true">#</a> 运算符优先级</h3><p>运算符的优先级从高到低如下所示排列，同一行的运算符具有相同的优先级。</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token operator">!</span><span class="token punctuation">,</span> <span class="token operator">-</span> <span class="token punctuation">(</span>单目<span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token operator">+</span> <span class="token punctuation">(</span>单目<span class="token punctuation">)</span>
<span class="token operator">*</span><span class="token punctuation">,</span> <span class="token operator">/</span><span class="token punctuation">,</span> <span class="token operator">DIV</span><span class="token punctuation">,</span> <span class="token operator">%</span><span class="token punctuation">,</span> MOD
<span class="token operator">-</span><span class="token punctuation">,</span> <span class="token operator">+</span>
<span class="token operator">=</span><span class="token punctuation">,</span> <span class="token operator">=</span><span class="token operator">=</span><span class="token punctuation">,</span> <span class="token operator">&lt;=&gt;</span><span class="token punctuation">,</span> <span class="token operator">&gt;=</span><span class="token punctuation">,</span> <span class="token operator">&gt;</span><span class="token punctuation">,</span> <span class="token operator">&lt;=</span><span class="token punctuation">,</span> <span class="token operator">&lt;</span><span class="token punctuation">,</span> <span class="token operator">&lt;&gt;</span><span class="token punctuation">,</span> <span class="token operator">!=</span>
<span class="token operator">LIKE</span><span class="token punctuation">,</span> <span class="token operator">REGEXP</span><span class="token punctuation">,</span> <span class="token operator">NOT</span> <span class="token operator">LIKE</span><span class="token punctuation">,</span> <span class="token operator">NOT</span> <span class="token operator">REGEXP</span>
<span class="token operator">BETWEEN</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span> <span class="token operator">AND</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">,</span> <span class="token operator">NOT</span> <span class="token operator">BETWEEN</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span> <span class="token operator">AND</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token operator">IS</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token operator">IS</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span>
<span class="token operator">IN</span><span class="token punctuation">,</span> <span class="token keyword">CONTAINS</span><span class="token punctuation">,</span> <span class="token operator">NOT</span> <span class="token operator">IN</span><span class="token punctuation">,</span> <span class="token operator">NOT</span> <span class="token keyword">CONTAINS</span>
<span class="token operator">AND</span><span class="token punctuation">,</span> <span class="token operator">&amp;</span><span class="token punctuation">,</span> <span class="token operator">&amp;&amp;</span>
<span class="token operator">OR</span><span class="token punctuation">,</span> <span class="token operator">|</span><span class="token punctuation">,</span> <span class="token operator">||</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><h2 id="内置函数列表" tabindex="-1"><a class="header-anchor" href="#内置函数列表" aria-hidden="true">#</a> 内置函数列表</h2><p>列表中的函数无须注册即可在 IoTDB 中使用，数据函数质量库中的函数需要参考注册步骤进行注册后才能使用。</p><h3 id="聚合函数" tabindex="-1"><a class="header-anchor" href="#聚合函数" aria-hidden="true">#</a> 聚合函数</h3><table><thead><tr><th>函数名</th><th>功能描述</th><th>允许的输入类型</th><th>输出类型</th></tr></thead><tbody><tr><td>SUM</td><td>求和。</td><td>INT32 INT64 FLOAT DOUBLE</td><td>DOUBLE</td></tr><tr><td>COUNT</td><td>计算数据点数。</td><td>所有类型</td><td>INT</td></tr><tr><td>AVG</td><td>求平均值。</td><td>INT32 INT64 FLOAT DOUBLE</td><td>DOUBLE</td></tr><tr><td>EXTREME</td><td>求具有最大绝对值的值。如果正值和负值的最大绝对值相等，则返回正值。</td><td>INT32 INT64 FLOAT DOUBLE</td><td>与输入类型一致</td></tr><tr><td>MAX_VALUE</td><td>求最大值。</td><td>INT32 INT64 FLOAT DOUBLE</td><td>与输入类型一致</td></tr><tr><td>MIN_VALUE</td><td>求最小值。</td><td>INT32 INT64 FLOAT DOUBLE</td><td>与输入类型一致</td></tr><tr><td>FIRST_VALUE</td><td>求时间戳最小的值。</td><td>所有类型</td><td>与输入类型一致</td></tr><tr><td>LAST_VALUE</td><td>求时间戳最大的值。</td><td>所有类型</td><td>与输入类型一致</td></tr><tr><td>MAX_TIME</td><td>求最大时间戳。</td><td>所有类型</td><td>Timestamp</td></tr><tr><td>MIN_TIME</td><td>求最小时间戳。</td><td>所有类型</td><td>Timestamp</td></tr><tr><td>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Aggregation.html" class="">聚合函数</a>。</td><td></td><td></td><td></td></tr></tbody></table><h3 id="数学函数" tabindex="-1"><a class="header-anchor" href="#数学函数" aria-hidden="true">#</a> 数学函数</h3><table><thead><tr><th>函数名</th><th>输入序列类型</th><th>输出序列类型</th><th>必要属性参数</th><th>Java 标准库中的对应实现</th></tr></thead><tbody><tr><td>SIN</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#sin(double)</td></tr><tr><td>COS</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#cos(double)</td></tr><tr><td>TAN</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#tan(double)</td></tr><tr><td>ASIN</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#asin(double)</td></tr><tr><td>ACOS</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#acos(double)</td></tr><tr><td>ATAN</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#atan(double)</td></tr><tr><td>SINH</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#sinh(double)</td></tr><tr><td>COSH</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#cosh(double)</td></tr><tr><td>TANH</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#tanh(double)</td></tr><tr><td>DEGREES</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#toDegrees(double)</td></tr><tr><td>RADIANS</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#toRadians(double)</td></tr><tr><td>ABS</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>与输入序列的实际类型一致</td><td></td><td>Math#abs(int) / Math#abs(long) /Math#abs(float) /Math#abs(double)</td></tr><tr><td>SIGN</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#signum(double)</td></tr><tr><td>CEIL</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#ceil(double)</td></tr><tr><td>FLOOR</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#floor(double)</td></tr><tr><td>ROUND</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td><code>places</code>:四舍五入有效位数，正数为小数点后面的有效位数，负数为整数位的有效位数</td><td>Math#rint(Math#pow(10,places))/Math#pow(10,places)</td></tr><tr><td>EXP</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#exp(double)</td></tr><tr><td>LN</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#log(double)</td></tr><tr><td>LOG10</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#log10(double)</td></tr><tr><td>SQRT</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td></td><td>Math#sqrt(double)</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Mathematical.html" class="">算数运算符和函数</a>。</p><h3 id="比较函数" tabindex="-1"><a class="header-anchor" href="#比较函数" aria-hidden="true">#</a> 比较函数</h3><table><thead><tr><th>函数名</th><th>可接收的输入序列类型</th><th>必要的属性参数</th><th>输出序列类型</th><th>功能类型</th></tr></thead><tbody><tr><td>ON_OFF</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>threshold</code>:DOUBLE</td><td>BOOLEAN</td><td>返回<code>ts_value &gt;= threshold</code>的bool值</td></tr><tr><td>IN_RANGE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>lower</code>:DOUBLE<br><code>upper</code>:DOUBLE</td><td>BOOLEAN</td><td>返回<code>ts_value &gt;= lower &amp;&amp; ts_value &lt;= upper</code>的bool值</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Comparison.html" class="">比较运算符和函数</a>。</p><h3 id="字符串处理函数" tabindex="-1"><a class="header-anchor" href="#字符串处理函数" aria-hidden="true">#</a> 字符串处理函数</h3><table><thead><tr><th>函数名</th><th>输入序列类型</th><th>必要的属性参数</th><th>输出序列类型</th><th>功能描述</th></tr></thead><tbody><tr><td>STRING_CONTAINS</td><td>TEXT</td><td><code>s</code>: 待搜寻的字符串</td><td>BOOLEAN</td><td>判断字符串中是否存在<code>s</code></td></tr><tr><td>STRING_MATCHES</td><td>TEXT</td><td><code>regex</code>: Java 标准库风格的正则表达式</td><td>BOOLEAN</td><td>判断字符串是否能够被正则表达式<code>regex</code>匹配</td></tr><tr><td>LENGTH</td><td>TEXT</td><td>无</td><td>INT32</td><td>返回字符串的长度</td></tr><tr><td>LOCATE</td><td>TEXT</td><td><code>target</code>: 需要被定位的子串 <br> <code>reverse</code>: 指定是否需要倒序定位，默认值为<code>false</code>, 即从左至右定位</td><td>INT32</td><td>获取<code>target</code>子串第一次出现在输入序列的位置，如果输入序列中不包含<code>target</code>则返回 -1</td></tr><tr><td>STARTSWITH</td><td>TEXT</td><td><code>target</code>: 需要匹配的前缀</td><td>BOOLEAN</td><td>判断字符串是否有指定前缀</td></tr><tr><td>ENDSWITH</td><td>TEXT</td><td><code>target</code>: 需要匹配的后缀</td><td>BOOLEAN</td><td>判断字符串是否有指定后缀</td></tr><tr><td>CONCAT</td><td>TEXT</td><td><code>targets</code>: 一系列 K-V, key需要以<code>target</code>为前缀且不重复, value是待拼接的字符串。<br><code>series_behind</code>: 指定拼接时时间序列是否在后面，默认为<code>false</code>。</td><td>TEXT</td><td>拼接字符串和<code>target</code>字串</td></tr><tr><td>SUBSTRING</td><td>TEXT</td><td><code>from</code>: 指定子串开始下标 <br><code>for</code>: 指定的字符个数之后停止</td><td>TEXT</td><td>提取字符串的子字符串，从指定的第一个字符开始，并在指定的字符数之后停止。下标从1开始。from 和 for的范围是 INT32 类型取值范围。</td></tr><tr><td>REPLACE</td><td>TEXT</td><td>第一个参数： 需要替换的目标子串<br>第二个参数：要替换成的子串</td><td>TEXT</td><td>将输入序列中的子串替换成目标子串</td></tr><tr><td>UPPER</td><td>TEXT</td><td>无</td><td>TEXT</td><td>将字符串转化为大写</td></tr><tr><td>LOWER</td><td>TEXT</td><td>无</td><td>TEXT</td><td>将字符串转化为小写</td></tr><tr><td>TRIM</td><td>TEXT</td><td>无</td><td>TEXT</td><td>移除字符串前后的空格</td></tr><tr><td>STRCMP</td><td>TEXT</td><td>无</td><td>TEXT</td><td>用于比较两个输入序列，如果值相同返回 <code>0</code> , 序列1的值小于序列2的值返回一个<code>负数</code>，序列1的值大于序列2的值返回一个<code>正数</code></td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/String.html" class="">字符串处理函数</a>。</p><h3 id="数据类型转换函数" tabindex="-1"><a class="header-anchor" href="#数据类型转换函数" aria-hidden="true">#</a> 数据类型转换函数</h3><table><thead><tr><th>函数名</th><th>必要的属性参数</th><th>输出序列类型</th><th>功能类型</th></tr></thead><tbody><tr><td>CAST</td><td><code>type</code>:输出的数据点的类型，只能是 INT32 / INT64 / FLOAT / DOUBLE / BOOLEAN / TEXT</td><td>由输入属性参数<code>type</code>决定</td><td>将数据转换为<code>type</code>参数指定的类型。</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Conversion.html" class="">数据类型转换</a>。</p><h3 id="常序列生成函数" tabindex="-1"><a class="header-anchor" href="#常序列生成函数" aria-hidden="true">#</a> 常序列生成函数</h3><table><thead><tr><th>函数名</th><th>必要的属性参数</th><th>输出序列类型</th><th>功能描述</th></tr></thead><tbody><tr><td>CONST</td><td><code>value</code>: 输出的数据点的值 <br><code>type</code>: 输出的数据点的类型，只能是 INT32 / INT64 / FLOAT / DOUBLE / BOOLEAN / TEXT</td><td>由输入属性参数 <code>type</code> 决定</td><td>根据输入属性 <code>value</code> 和 <code>type</code> 输出用户指定的常序列。</td></tr><tr><td>PI</td><td>无</td><td>DOUBLE</td><td>常序列的值：<code>π</code> 的 <code>double</code> 值，圆的周长与其直径的比值，即圆周率，等于 <em>Java标准库</em> 中的<code>Math.PI</code>。</td></tr><tr><td>E</td><td>无</td><td>DOUBLE</td><td>常序列的值：<code>e</code> 的 <code>double</code> 值，自然对数的底，它等于 <em>Java 标准库</em> 中的 <code>Math.E</code>。</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Constant.html" class="">常序列生成函数</a>。</p><h3 id="选择函数" tabindex="-1"><a class="header-anchor" href="#选择函数" aria-hidden="true">#</a> 选择函数</h3><table><thead><tr><th>函数名</th><th>输入序列类型</th><th>必要的属性参数</th><th>输出序列类型</th><th>功能描述</th></tr></thead><tbody><tr><td>TOP_K</td><td>INT32 / INT64 / FLOAT / DOUBLE / TEXT</td><td><code>k</code>: 最多选择的数据点数，必须大于 0 小于等于 1000</td><td>与输入序列的实际类型一致</td><td>返回某时间序列中值最大的<code>k</code>个数据点。若多于<code>k</code>个数据点的值并列最大，则返回时间戳最小的数据点。</td></tr><tr><td>BOTTOM_K</td><td>INT32 / INT64 / FLOAT / DOUBLE / TEXT</td><td><code>k</code>: 最多选择的数据点数，必须大于 0 小于等于 1000</td><td>与输入序列的实际类型一致</td><td>返回某时间序列中值最小的<code>k</code>个数据点。若多于<code>k</code>个数据点的值并列最小，则返回时间戳最小的数据点。</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Selection.html" class="">选择函数</a>。</p><h3 id="区间查询函数" tabindex="-1"><a class="header-anchor" href="#区间查询函数" aria-hidden="true">#</a> 区间查询函数</h3><table><thead><tr><th>函数名</th><th>输入序列类型</th><th>属性参数</th><th>输出序列类型</th><th>功能描述</th></tr></thead><tbody><tr><td>ZERO_DURATION</td><td>INT32/ INT64/ FLOAT/ DOUBLE/ BOOLEAN</td><td><code>min</code>:可选，默认值0<br><code>max</code>:可选，默认值<code>Long.MAX_VALUE</code></td><td>Long</td><td>返回时间序列连续为0(false)的开始时间与持续时间，持续时间t(单位ms)满足<code>t &gt;= min &amp;&amp; t &lt;= max</code></td></tr><tr><td>NON_ZERO_DURATION</td><td>INT32/ INT64/ FLOAT/ DOUBLE/ BOOLEAN</td><td><code>min</code>:可选，默认值0<br><code>max</code>:可选，默认值<code>Long.MAX_VALUE</code></td><td>Long</td><td>返回时间序列连续不为0(false)的开始时间与持续时间，持续时间t(单位ms)满足<code>t &gt;= min &amp;&amp; t &lt;= max</code></td></tr><tr><td>ZERO_COUNT</td><td>INT32/ INT64/ FLOAT/ DOUBLE/ BOOLEAN</td><td><code>min</code>:可选，默认值1<br><code>max</code>:可选，默认值<code>Long.MAX_VALUE</code></td><td>Long</td><td>返回时间序列连续为0(false)的开始时间与其后数据点的个数，数据点个数n满足<code>n &gt;= min &amp;&amp; n &lt;= max</code></td></tr><tr><td>NON_ZERO_COUNT</td><td>INT32/ INT64/ FLOAT/ DOUBLE/ BOOLEAN</td><td><code>min</code>:可选，默认值1<br><code>max</code>:可选，默认值<code>Long.MAX_VALUE</code></td><td>Long</td><td>返回时间序列连续不为0(false)的开始时间与其后数据点的个数，数据点个数n满足<code>n &gt;= min &amp;&amp; n &lt;= max</code></td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Continuous-Interval.html" class="">区间查询函数</a>。</p><h3 id="趋势计算函数" tabindex="-1"><a class="header-anchor" href="#趋势计算函数" aria-hidden="true">#</a> 趋势计算函数</h3><table><thead><tr><th>函数名</th><th>输入序列类型</th><th>输出序列类型</th><th>功能描述</th></tr></thead><tbody><tr><td>TIME_DIFFERENCE</td><td>INT32 / INT64 / FLOAT / DOUBLE / BOOLEAN / TEXT</td><td>INT64</td><td>统计序列中某数据点的时间戳与前一数据点时间戳的差。范围内第一个数据点没有对应的结果输出。</td></tr><tr><td>DIFFERENCE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>与输入序列的实际类型一致</td><td>统计序列中某数据点的值与前一数据点的值的差。范围内第一个数据点没有对应的结果输出。</td></tr><tr><td>NON_NEGATIVE_DIFFERENCE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>与输入序列的实际类型一致</td><td>统计序列中某数据点的值与前一数据点的值的差的绝对值。范围内第一个数据点没有对应的结果输出。</td></tr><tr><td>DERIVATIVE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td>统计序列中某数据点相对于前一数据点的变化率，数量上等同于 DIFFERENCE / TIME_DIFFERENCE。范围内第一个数据点没有对应的结果输出。</td></tr><tr><td>NON_NEGATIVE_DERIVATIVE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>DOUBLE</td><td>统计序列中某数据点相对于前一数据点的变化率的绝对值，数量上等同于 NON_NEGATIVE_DIFFERENCE / TIME_DIFFERENCE。范围内第一个数据点没有对应的结果输出。</td></tr></tbody></table><table><thead><tr><th>函数名</th><th>输入序列类型</th><th>参数</th><th>输出序列类型</th><th>功能描述</th></tr></thead><tbody><tr><td>DIFF</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>ignoreNull</code>：可选，默认为true；为true时，前一个数据点值为null时，忽略该数据点继续向前找到第一个出现的不为null的值；为false时，如果前一个数据点为null，则不忽略，使用null进行相减，结果也为null</td><td>DOUBLE</td><td>统计序列中某数据点的值与前一数据点的值的差。第一个数据点没有对应的结果输出，输出值为null</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Variation-Trend.html" class="">趋势计算函数</a>。</p><h3 id="采样函数" tabindex="-1"><a class="header-anchor" href="#采样函数" aria-hidden="true">#</a> 采样函数</h3><table><thead><tr><th>函数名</th><th>可接收的输入序列类型</th><th>必要的属性参数</th><th>输出序列类型</th><th>功能类型</th></tr></thead><tbody><tr><td>EQUAL_SIZE_BUCKET_RANDOM_SAMPLE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>降采样比例 <code>proportion</code>，取值范围为<code>(0, 1]</code>，默认为<code>0.1</code></td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>返回符合采样比例的等分桶随机采样</td></tr><tr><td>EQUAL_SIZE_BUCKET_AGG_SAMPLE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>proportion</code>取值范围为<code>(0, 1]</code>，默认为<code>0.1</code><br><code>type</code>:取值类型有<code>avg</code>, <code>max</code>, <code>min</code>, <code>sum</code>, <code>extreme</code>, <code>variance</code>, 默认为<code>avg</code></td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>返回符合采样比例的等分桶聚合采样</td></tr><tr><td>EQUAL_SIZE_BUCKET_M4_SAMPLE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>proportion</code>取值范围为<code>(0, 1]</code>，默认为<code>0.1</code></td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>返回符合采样比例的等分桶M4采样</td></tr><tr><td>EQUAL_SIZE_BUCKET_OUTLIER_SAMPLE</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>proportion</code>取值范围为<code>(0, 1]</code>，默认为<code>0.1</code><br><code>type</code>取值为<code>avg</code>或<code>stendis</code>或<code>cos</code>或<code>prenextdis</code>，默认为<code>avg</code><br><code>number</code>取值应大于0，默认<code>3</code></td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>返回符合采样比例和桶内采样个数的等分桶离群值采样</td></tr><tr><td>M4</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>包含固定点数的窗口和滑动时间窗口使用不同的属性参数。包含固定点数的窗口使用属性<code>windowSize</code>和<code>slidingStep</code>。滑动时间窗口使用属性<code>timeInterval</code>、<code>slidingStep</code>、<code>displayWindowBegin</code>和<code>displayWindowEnd</code>。更多细节见下文。</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td>返回每个窗口内的第一个点（<code>first</code>）、最后一个点（<code>last</code>）、最小值点（<code>bottom</code>）、最大值点（<code>top</code>）。在一个窗口内的聚合点输出之前，M4会将它们按照时间戳递增排序并且去重。</td></tr></tbody></table><h2 id="条件表达式" tabindex="-1"><a class="header-anchor" href="#条件表达式" aria-hidden="true">#</a> 条件表达式</h2><table><thead><tr><th>表达式名称</th><th>含义</th></tr></thead><tbody><tr><td><code>CASE</code></td><td>类似if else</td></tr></tbody></table><p>详细说明及示例见文档 <a href="/zh/UserGuide/V1.2.x/Operators-Functions/Conditional.html" class="">条件表达式</a></p><h2 id="数据质量函数库" tabindex="-1"><a class="header-anchor" href="#数据质量函数库" aria-hidden="true">#</a> 数据质量函数库</h2><p>对基于时序数据的应用而言，数据质量至关重要。基于用户自定义函数能力，IoTDB 提供了一系列关于数据质量的函数，包括数据画像、数据质量评估与修复等，能够满足工业领域对数据质量的需求。</p><p><strong>该函数库中的函数不是内置函数，使用前要先加载到系统中。</strong> 操作流程如下：</p><ol><li>下载包含全部依赖的 jar 包和注册脚本 <a href="https://archive.apache.org/dist/iotdb/1.0.1/apache-iotdb-1.0.1-library-udf-bin.zip" target="_blank" rel="noopener noreferrer">【点击下载】<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span></a> ；</li><li>将 jar 包复制到 IoTDB 程序目录的 <code>ext\udf</code> 目录下 (若您使用的是集群，请将jar包复制到所有DataNode的该目录下)；</li><li>启动 IoTDB；</li><li>将注册脚本复制到 IoTDB 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