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auto-link vp-sidebar-link" href="/zh/UserGuide/latest-Table/SQL-Manual/Limit-Offset-Clause.html" aria-label="LIMIT&OFFSET子句"><!---->LIMIT&OFFSET子句<!----></a></li><li><a class="route-link auto-link vp-sidebar-link" href="/zh/UserGuide/latest-Table/SQL-Manual/Nested-Queries.html" aria-label="嵌套查询"><!---->嵌套查询<!----></a></li></ul></section></li><li><a class="route-link auto-link vp-sidebar-link" href="/zh/UserGuide/latest-Table/SQL-Manual/SQL-Maintenance-Statements_apache.html" aria-label="运维语句"><!---->运维语句<!----></a></li><li><a class="route-link auto-link vp-sidebar-link" href="/zh/UserGuide/latest-Table/SQL-Manual/Identifier.html" aria-label="标识符"><!---->标识符<!----></a></li><li><a class="route-link auto-link vp-sidebar-link" href="/zh/UserGuide/latest-Table/SQL-Manual/Keywords.html" aria-label="保留字&关键字"><!---->保留字&关键字<!----></a></li><li><section class="vp-sidebar-group"><button class="vp-sidebar-header clickable" type="button"><!----><span class="vp-sidebar-title">函数与操作符</span><span class="vp-arrow end"></span></button><!----></section></li></ul></section></li><li><section class="vp-sidebar-group"><button class="vp-sidebar-header clickable" type="button"><!----><span class="vp-sidebar-title">技术内幕</span><span class="vp-arrow end"></span></button><!----></section></li><li><section class="vp-sidebar-group"><button class="vp-sidebar-header clickable" type="button"><!----><span class="vp-sidebar-title">附录</span><span class="vp-arrow end"></span></button><!----></section></li><li><section class="vp-sidebar-group"><button class="vp-sidebar-header clickable" type="button"><!----><span class="vp-sidebar-title">FAQ</span><span class="vp-arrow end"></span></button><!----></section></li></ul><!----></aside><!--[--><main id="main-content" class="vp-page"><!--[--><!----><!----><nav class="vp-breadcrumb disable"></nav><div class="vp-page-title"><h1><!---->SELECT 子句</h1><div class="page-info"><!----><!----><span class="page-date-info" aria-label="写作日期📅" data-balloon-pos="up"><svg xmlns="http://www.w3.org/2000/svg" class="icon calendar-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="calendar icon" name="calendar"><path d="M716.4 110.137c0-18.753-14.72-33.473-33.472-33.473-18.753 0-33.473 14.72-33.473 33.473v33.473h66.993v-33.473zm-334.87 0c0-18.753-14.72-33.473-33.473-33.473s-33.52 14.72-33.52 33.473v33.473h66.993v-33.473zm468.81 33.52H716.4v100.465c0 18.753-14.72 33.473-33.472 33.473a33.145 33.145 0 01-33.473-33.473V143.657H381.53v100.465c0 18.753-14.72 33.473-33.473 33.473a33.145 33.145 0 01-33.473-33.473V143.657H180.6A134.314 134.314 0 0046.66 277.595v535.756A134.314 134.314 0 00180.6 947.289h669.74a134.36 134.36 0 00133.94-133.938V277.595a134.314 134.314 0 00-133.94-133.938zm33.473 267.877H147.126a33.145 33.145 0 01-33.473-33.473c0-18.752 14.72-33.473 33.473-33.473h736.687c18.752 0 33.472 14.72 33.472 33.473a33.145 33.145 0 01-33.472 33.473z"></path></svg><span data-allow-mismatch="text">2025/1/3</span><meta property="datePublished" content="2025-01-03T10:29:25.000Z"></span><!----><span class="page-reading-time-info" aria-label="阅读时间⌛" data-balloon-pos="up"><svg xmlns="http://www.w3.org/2000/svg" class="icon timer-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="timer icon" name="timer"><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 10 分钟</span><meta property="timeRequired" content="PT10M"></span><!----><!----></div><hr></div><!----><div class="" vp-content><!----><div id="markdown-content"><h1 id="select-子句" tabindex="-1"><a class="header-anchor" href="#select-子句"><span>SELECT 子句</span></a></h1><h2 id="_1-语法概览" tabindex="-1"><a class="header-anchor" href="#_1-语法概览"><span>1. 语法概览</span></a></h2><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#C678DD;">SELECT</span><span style="color:#ABB2BF;"> setQuantifier? selectItem (</span><span style="color:#98C379;">','</span><span style="color:#ABB2BF;"> selectItem)*</span></span> |
| <span class="line"></span> |
| <span class="line"><span style="color:#ABB2BF;">selectItem</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> : expression (</span><span style="color:#C678DD;">AS</span><span style="color:#ABB2BF;">? identifier)? #selectSingle</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> | tableName </span><span style="color:#98C379;">'.'</span><span style="color:#ABB2BF;"> ASTERISK (</span><span style="color:#C678DD;">AS</span><span style="color:#ABB2BF;"> columnAliases)? #selectAll</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> | ASTERISK #selectAll</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> ;</span></span> |
| <span class="line"><span style="color:#ABB2BF;">setQuantifier</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> : </span><span style="color:#C678DD;">DISTINCT</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> | ALL</span></span> |
| <span class="line"><span style="color:#ABB2BF;"> ;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 class="line-number"></div></div></div><ul><li><strong>SELECT 子句</strong>: 指定了查询结果应包含的列，包含聚合函数（如 SUM、AVG、COUNT 等）以及窗口函数，在逻辑上最后执行。</li><li><strong>DISTINCT 关键字</strong>: <code>SELECT DISTINCT column_name</code> 确保查询结果中的值是唯一的，去除重复项。</li><li><strong>COLUMNS 函数</strong>：SELECT 子句中支持使用 COLUMNS 函数进行列筛选，并支持和表达式结合使用，使表达式的效果对所有筛选出的列生效。</li></ul><h2 id="_2-语法详释" tabindex="-1"><a class="header-anchor" href="#_2-语法详释"><span>2. 语法详释：</span></a></h2><p>每个 <code>selectItem</code> 可以是以下形式之一：</p><ul><li><strong>表达式</strong>: <code>expression [ [ AS ] column_alias ]</code> 定义单个输出列，可以指定列别名。</li><li><strong>选择某个关系的所有列</strong>: <code>relation.*</code> 选择某个关系的所有列，不允许使用列别名。</li><li><strong>选择结果集中的所有列</strong>: <code>*</code> 选择查询的所有列，不允许使用列别名。</li></ul><p><code>DISTINCT</code> 的使用场景：</p><ul><li><strong>SELECT 语句</strong>：在 SELECT 语句中使用 DISTINCT，查询结果去除重复项。</li><li><strong>聚合函数</strong>：与聚合函数一起使用时，DISTINCT 只处理输入数据集中的非重复行。</li><li><strong>GROUP BY 子句</strong>：在 GROUP BY 子句中使用 ALL 和 DISTINCT 量词，决定是否每个重复的分组集产生不同的输出行。</li></ul><p><code>COLUMNS</code> 函数：</p><ul><li><strong><code>COLUMNS(*)</code></strong>: 匹配所有列，支持结合表达式进行使用。</li><li><strong><code>COLUMNS(regexStr) ? AS identifier</code></strong>：正则匹配 <ul><li><p>匹配所有列名满足正则表达式的列，支持结合表达式进行使用。</p></li><li><p>支持引用正则表达式捕获到的 groups 对列进行重命名，不写 AS 时展示原始列名（即 _coln_原始列名，其中 n 为列在结果表中的 position）。</p></li><li><p>重命名用法简述：</p><ul><li>regexStr 中使用圆括号设置要捕获的组；</li><li>在 identifier 中使用 <code>'$index'</code> 引用捕获到的组。</li></ul><p>注意：使用该功能时，identifier 中会包含特殊字符 '$'，所以整个 identifier 要用双引号引起来。</p></li></ul></li></ul><h2 id="_3-示例数据" tabindex="-1"><a class="header-anchor" href="#_3-示例数据"><span>3. 示例数据</span></a></h2><p>在<a class="route-link" href="/zh/UserGuide/latest-Table/Reference/Sample-Data.html">示例数据页面</a>中，包含了用于构建表结构和插入数据的SQL语句，下载并在IoTDB CLI中执行这些语句，即可将数据导入IoTDB，您可以使用这些数据来测试和执行示例中的SQL语句，并获得相应的结果。</p><h3 id="_3-1-选择列表" tabindex="-1"><a class="header-anchor" href="#_3-1-选择列表"><span>3.1 选择列表</span></a></h3><h4 id="_3-1-1-星表达式" tabindex="-1"><a class="header-anchor" href="#_3-1-1-星表达式"><span>3.1.1 星表达式</span></a></h4><p>使用星号(*)可以选取表中的所有列，<strong>注意</strong>，星号表达式不能被大多数函数转换，除了<code>count(*)</code>的情况。</p><p>示例：从表中选择所有列</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#C678DD;">SELECT</span><span style="color:#ABB2BF;"> * </span><span style="color:#C678DD;">FROM</span><span style="color:#ABB2BF;"> table1;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><div class="line-number"></div></div></div><p>执行结果如下：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">time</span><span style="color:#ABB2BF;">|region|plant_id|device_id|model_id|maintenance|temperature|humidity|</span><span style="color:#C678DD;">status</span><span style="color:#ABB2BF;">| modifytime|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T18:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">4</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T18:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">15</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T08:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T08:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">09</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T09:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">88</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">12</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">25</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T09:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| F| </span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T14:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| F| </span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">8</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T14:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">17</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| D| </span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">13</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">01</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">39</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">3</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">03</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">41</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">04</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">42</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| false| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">43</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| false| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">44</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| false|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Total </span><span style="color:#C678DD;">line</span><span style="color:#C678DD;"> number</span><span style="color:#56B6C2;"> =</span><span style="color:#D19A66;"> 18</span></span> |
| <span class="line"><span style="color:#ABB2BF;">It costs </span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">.653s</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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 class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><h4 id="_3-1-2-聚合函数" tabindex="-1"><a class="header-anchor" href="#_3-1-2-聚合函数"><span>3.1.2 聚合函数</span></a></h4><p>聚合函数将多行数据汇总为单个值。当 SELECT 子句中存在聚合函数时，查询将被视为聚合查询。在聚合查询中，所有表达式必须是聚合函数的一部分或由<a class="route-link" href="/zh/UserGuide/latest-Table/SQL-Manual/GroupBy-Clause.html">GROUP BY子句</a>指定的分组的一部分。</p><p>示例1：返回地址表中的总行数：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#C678DD;">SELECT</span><span style="color:#56B6C2;"> count</span><span style="color:#ABB2BF;">(*) </span><span style="color:#C678DD;">FROM</span><span style="color:#ABB2BF;"> table1;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><div class="line-number"></div></div></div><p>执行结果如下：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|_col0|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">18</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Total </span><span style="color:#C678DD;">line</span><span style="color:#C678DD;"> number</span><span style="color:#56B6C2;"> =</span><span style="color:#D19A66;"> 1</span></span> |
| <span class="line"><span style="color:#ABB2BF;">It costs </span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">.091s</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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><p>示例2：返回按城市分组的地址表中的总行数：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#C678DD;">SELECT</span><span style="color:#ABB2BF;"> region, </span><span style="color:#56B6C2;">count</span><span style="color:#ABB2BF;">(*) </span></span> |
| <span class="line"><span style="color:#C678DD;"> FROM</span><span style="color:#ABB2BF;"> table1 </span></span> |
| <span class="line"><span style="color:#C678DD;"> GROUP BY</span><span style="color:#ABB2BF;"> region;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>执行结果如下：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">------+-----+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|region|_col1|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">------+-----+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">------+-----+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Total </span><span style="color:#C678DD;">line</span><span style="color:#C678DD;"> number</span><span style="color:#56B6C2;"> =</span><span style="color:#D19A66;"> 2</span></span> |
| <span class="line"><span style="color:#ABB2BF;">It costs </span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">.071s</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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><h4 id="_3-1-3-别名" tabindex="-1"><a class="header-anchor" href="#_3-1-3-别名"><span>3.1.3 别名</span></a></h4><p>关键字<code>AS</code>：为选定的列指定别名，别名将覆盖已存在的列名，以提高查询结果的可读性。</p><p>示例1：原始表格：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">IoTDB</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> SELECT</span><span style="color:#ABB2BF;"> * </span><span style="color:#C678DD;">FROM</span><span style="color:#ABB2BF;"> table1;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><div class="line-number"></div></div></div><p>执行结果如下：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">time</span><span style="color:#ABB2BF;">|region|plant_id|device_id|model_id|maintenance|temperature|humidity|</span><span style="color:#C678DD;">status</span><span style="color:#ABB2BF;">| modifytime|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T18:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">4</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T18:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">15</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T08:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T08:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">09</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T09:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">88</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">12</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">25</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T09:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| F| </span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T14:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| F| </span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">8</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T14:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">17</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| D| </span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">13</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">01</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">39</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">3</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">03</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">41</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">04</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">42</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| false| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">43</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| false| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">44</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 北京| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| false|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Total </span><span style="color:#C678DD;">line</span><span style="color:#C678DD;"> number</span><span style="color:#56B6C2;"> =</span><span style="color:#D19A66;"> 18</span></span> |
| <span class="line"><span style="color:#ABB2BF;">It costs </span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">.653s</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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 class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>示例2：单列设置别名：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">IoTDB</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> SELECT</span><span style="color:#ABB2BF;"> device_id </span></span> |
| <span class="line"><span style="color:#C678DD;"> AS</span><span style="color:#ABB2BF;"> device </span></span> |
| <span class="line"><span style="color:#C678DD;"> FROM</span><span style="color:#ABB2BF;"> table1;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>执行结果如下：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|device|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Total </span><span style="color:#C678DD;">line</span><span style="color:#C678DD;"> number</span><span style="color:#56B6C2;"> =</span><span style="color:#D19A66;"> 18</span></span> |
| <span class="line"><span style="color:#ABB2BF;">It costs </span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">.053s</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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 class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>示例3：所有列的别名：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">IoTDB</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> SELECT</span><span style="color:#ABB2BF;"> table1.* </span></span> |
| <span class="line"><span style="color:#C678DD;"> AS</span><span style="color:#ABB2BF;"> (</span><span style="color:#C678DD;">timestamp</span><span style="color:#ABB2BF;">, Reg, Pl, DevID, Mod, Mnt, Temp, Hum, Stat,MTime) </span></span> |
| <span class="line"><span style="color:#C678DD;"> FROM</span><span style="color:#ABB2BF;"> table1;</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>执行结果如下：</p><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+----+----+-----+---+---+----+----+-----+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">TIMESTAMP</span><span style="color:#ABB2BF;">| REG| PL|DEVID|MOD|MNT|TEMP| HUM| STAT| MTIME|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+----+----+-----+---+---+----+----+-----+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T18:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">4</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T18:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">15</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T08:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T08:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">09</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T09:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">88</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">12</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">25</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T09:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| F|</span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T14:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| F|</span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">8</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-30T14:</span><span style="color:#D19A66;">30</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">17</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|上海|</span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| D|</span><span style="color:#D19A66;">360</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T10:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">13</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">38</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">01</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">39</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">3</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">03</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">41</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">04</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">42</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">35</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">2</span><span style="color:#ABB2BF;">|false| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">43</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|false| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-27T16:</span><span style="color:#D19A66;">44</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|北京|</span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">101</span><span style="color:#ABB2BF;">| B|</span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|false|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T16:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+----+----+-----+---+---+----+----+-----+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Total </span><span style="color:#C678DD;">line</span><span style="color:#C678DD;"> number</span><span style="color:#56B6C2;"> =</span><span style="color:#D19A66;"> 18</span></span> |
| <span class="line"><span style="color:#ABB2BF;">It costs </span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">.189s</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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 class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><h3 id="_3-2-columns-函数" tabindex="-1"><a class="header-anchor" href="#_3-2-columns-函数"><span>3.2 Columns 函数</span></a></h3><ol><li>不结合表达式</li></ol><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#7F848E;font-style:italic;">-- 查询列名以 'm' 开头的列的数据</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#ABB2BF;"> columns(</span><span style="color:#98C379;">'^m.*'</span><span style="color:#ABB2BF;">) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1 </span><span style="color:#C678DD;">limit</span><span style="color:#D19A66;"> 5</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------+-----------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|model_id|maintenance|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------+-----------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------+-----------+</span></span> |
| <span class="line"></span> |
| <span class="line"></span> |
| <span class="line"><span style="color:#7F848E;font-style:italic;">-- 查询列名以 'o' 开头的列，未匹配到任何列，抛出异常</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#ABB2BF;"> columns(</span><span style="color:#98C379;">'^o.*'</span><span style="color:#ABB2BF;">) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1 </span><span style="color:#C678DD;">limit</span><span style="color:#D19A66;"> 5</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Msg: </span><span style="color:#D19A66;">org</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">apache</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">iotdb</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">jdbc</span><span style="color:#ABB2BF;">.IoTDBSQLException: </span><span style="color:#D19A66;">701</span><span style="color:#ABB2BF;">: </span><span style="color:#C678DD;">No</span><span style="color:#ABB2BF;"> matching columns found that </span><span style="color:#C678DD;">match</span><span style="color:#ABB2BF;"> regex </span><span style="color:#98C379;">'^o.*'</span></span> |
| <span class="line"></span> |
| <span class="line"></span> |
| <span class="line"><span style="color:#7F848E;font-style:italic;">-- 查询列名以 'm' 开头的列的数据，并重命名以 'series_' 开头</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#ABB2BF;"> columns(</span><span style="color:#98C379;">'^m(.*)'</span><span style="color:#ABB2BF;">) </span><span style="color:#C678DD;">AS</span><span style="color:#98C379;"> "series_$0"</span><span style="color:#C678DD;"> from</span><span style="color:#ABB2BF;"> table1 </span><span style="color:#C678DD;">limit</span><span style="color:#D19A66;"> 5</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">---------------+------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|series_model_id|series_maintenance|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">---------------+------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">---------------+------------------+</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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 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><ol start="2"><li>结合表达式</li></ol><ul><li>单个 COLUMNS 函数</li></ul><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#7F848E;font-style:italic;">-- 查询所有列的最小值</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#56B6C2;"> min</span><span style="color:#ABB2BF;">(columns(*)) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------------+--------------+---------------+--------------+-----------------+-----------------+--------------+------------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| _col0_time|_col1_region|_col2_plant_id|_col3_device_id|_col4_model_id|_col5_maintenance|_col6_temperature|_col7_humidity|_col8_status| _col9_arrival_time|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------------+--------------+---------------+--------------+-----------------+-----------------+--------------+------------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">1001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| A| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">85</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">8</span><span style="color:#ABB2BF;">| false|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-26T13:</span><span style="color:#D19A66;">37</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------------+--------------+---------------+--------------+-----------------+-----------------+--------------+------------+-----------------------------+</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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><ul><li>多个 COLUMNS 函数，出现在同一表达式</li></ul><blockquote><p>使用限制：出现多个 COLUMNS 函数时，多个 COLUMNS 函数的参数要完全相同</p></blockquote><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#7F848E;font-style:italic;">-- 查询 'h' 开头列的最小值和最大值之和</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#56B6C2;"> min</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">)) + </span><span style="color:#56B6C2;">max</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">)) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|_col0_humidity|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">79</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">899994</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+</span></span> |
| <span class="line"></span> |
| <span class="line"><span style="color:#7F848E;font-style:italic;">-- 错误查询，两个 COLUMNS 函数不完全相同</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#56B6C2;"> min</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">)) + </span><span style="color:#56B6C2;">max</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^t.*'</span><span style="color:#ABB2BF;">)) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1</span></span> |
| <span class="line"><span style="color:#ABB2BF;">Msg: </span><span style="color:#D19A66;">org</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">apache</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">iotdb</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">jdbc</span><span style="color:#ABB2BF;">.IoTDBSQLException: </span><span style="color:#D19A66;">701</span><span style="color:#ABB2BF;">: Multiple different COLUMNS </span><span style="color:#C678DD;">in</span><span style="color:#ABB2BF;"> the same expression are </span><span style="color:#C678DD;">not</span><span style="color:#C678DD;"> supported</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 class="line-number"></div></div></div><ul><li>多个 COLUMNS 函数，出现在不同表达式</li></ul><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#7F848E;font-style:italic;">-- 分别查询 'h' 开头列的最小值和最大值</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#56B6C2;"> min</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">)) , </span><span style="color:#56B6C2;">max</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">)) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+--------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|_col0_humidity|_col1_humidity|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+--------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">8</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+--------------+</span></span> |
| <span class="line"></span> |
| <span class="line"><span style="color:#7F848E;font-style:italic;">-- 分别查询 'h' 开头列的最小值和 'te'开头列的最大值</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#56B6C2;"> min</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">)) , </span><span style="color:#56B6C2;">max</span><span style="color:#ABB2BF;">(columns(</span><span style="color:#98C379;">'^te.*'</span><span style="color:#ABB2BF;">)) </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+-----------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|_col0_humidity|_col1_temperature|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+-----------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">34</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">8</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">--------------+-----------------+</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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><ol start="3"><li>在 WHERE 子句中使用</li></ol><div class="language-sql line-numbers-mode" data-highlighter="shiki" data-ext="sql" style="background-color:#282c34;color:#abb2bf;"><pre class="shiki one-dark-pro vp-code"><code class="language-sql"><span class="line"><span style="color:#7F848E;font-style:italic;">-- 查询数据，所有 'h' 开头列的数据必须要大于 40</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#ABB2BF;"> * </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1 </span><span style="color:#C678DD;">where</span><span style="color:#ABB2BF;"> columns(</span><span style="color:#98C379;">'^h.*'</span><span style="color:#ABB2BF;">) </span><span style="color:#56B6C2;">></span><span style="color:#D19A66;"> 40</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">time</span><span style="color:#ABB2BF;">|region|plant_id|device_id|model_id|maintenance|temperature|humidity|</span><span style="color:#C678DD;">status</span><span style="color:#ABB2BF;">| arrival_time|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T09:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">88</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">12</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"></span> |
| <span class="line"><span style="color:#7F848E;font-style:italic;">--等价于</span></span> |
| <span class="line"><span style="color:#ABB2BF;">IoTDB:database1</span><span style="color:#56B6C2;">></span><span style="color:#C678DD;"> select</span><span style="color:#ABB2BF;"> * </span><span style="color:#C678DD;">from</span><span style="color:#ABB2BF;"> table1 </span><span style="color:#C678DD;">where</span><span style="color:#ABB2BF;"> humidity </span><span style="color:#56B6C2;">></span><span style="color:#D19A66;"> 40</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">time</span><span style="color:#ABB2BF;">|region|plant_id|device_id|model_id|maintenance|temperature|humidity|</span><span style="color:#C678DD;">status</span><span style="color:#ABB2BF;">| arrival_time|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-29T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3002</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| E| </span><span style="color:#D19A66;">180</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T09:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">40</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">9</span><span style="color:#ABB2BF;">| true| </span><span style="color:#C678DD;">null</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">| 上海| </span><span style="color:#D19A66;">3001</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">100</span><span style="color:#ABB2BF;">| C| </span><span style="color:#D19A66;">90</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">88</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">0</span><span style="color:#ABB2BF;">| </span><span style="color:#D19A66;">45</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">1</span><span style="color:#ABB2BF;">| true|</span><span style="color:#D19A66;">2024</span><span style="color:#ABB2BF;">-</span><span style="color:#D19A66;">11</span><span style="color:#ABB2BF;">-28T11:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">12</span><span style="color:#ABB2BF;">.</span><span style="color:#D19A66;">000</span><span style="color:#ABB2BF;">+</span><span style="color:#D19A66;">08</span><span style="color:#ABB2BF;">:</span><span style="color:#D19A66;">00</span><span style="color:#ABB2BF;">|</span></span> |
| <span class="line"><span style="color:#ABB2BF;">+</span><span style="color:#7F848E;font-style:italic;">-----------------------------+------+--------+---------+--------+-----------+-----------+--------+------+-----------------------------+</span></span></code></pre><div class="line-numbers" aria-hidden="true" style="counter-reset:line-number 0;"><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 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="_4-结果集列顺序" tabindex="-1"><a class="header-anchor" href="#_4-结果集列顺序"><span>4. 结果集列顺序</span></a></h2><ul><li><strong>列顺序</strong>: 结果集中的列顺序与 SELECT 子句中指定的顺序相同。</li><li><strong>多列排序</strong>: 如果选择表达式返回多个列，它们的排序方式与源关系中的排序方式相同</li></ul></div><!----><!----><!----></div><footer class="vp-page-meta"><div class="vp-meta-item edit-link"><a class="auto-link external-link vp-meta-label" href="https://github.com/apache/iotdb-docs/edit/main/src/zh/UserGuide/latest-Table/SQL-Manual/Select-Clause_apache.md" aria-label="发现错误？在 GitHub 上编辑此页" rel="noopener noreferrer" target="_blank"><!--[--><svg xmlns="http://www.w3.org/2000/svg" class="icon edit-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="edit icon" name="edit"><path d="M430.818 653.65a60.46 60.46 0 0 1-50.96-93.281l71.69-114.012 7.773-10.365L816.038 80.138A60.46 60.46 0 0 1 859.225 62a60.46 60.46 0 0 1 43.186 18.138l43.186 43.186a60.46 60.46 0 0 1 0 86.373L588.879 565.55l-8.637 8.637-117.466 68.234a60.46 60.46 0 0 1-31.958 11.229z"></path><path d="M728.802 962H252.891A190.883 190.883 0 0 1 62.008 771.98V296.934a190.883 190.883 0 0 1 190.883-192.61h267.754a60.46 60.46 0 0 1 0 120.92H252.891a69.962 69.962 0 0 0-69.098 69.099V771.98a69.962 69.962 0 0 0 69.098 69.098h475.911A69.962 69.962 0 0 0 797.9 771.98V503.363a60.46 60.46 0 1 1 120.922 0V771.98A190.883 190.883 0 0 1 728.802 962z"></path></svg><!--]-->发现错误？在 GitHub 上编辑此页<!----></a></div><div class="vp-meta-item git-info"><div class="update-time"><span class="vp-meta-label">最近更新: </span><time class="vp-meta-info" datetime="2026-04-15T10:39:00.000Z" data-allow-mismatch>2026/4/15 10:39</time></div><!----></div></footer><nav class="vp-page-nav"><a class="route-link auto-link prev" href="/zh/UserGuide/latest-Table/SQL-Manual/overview_apache.html" aria-label="概览"><div class="hint"><span class="arrow start"></span>上一页</div><div class="link"><!---->概览</div></a><a class="route-link auto-link next" href="/zh/UserGuide/latest-Table/SQL-Manual/From-Join-Clause.html" aria-label="FROM&JOIN子句"><div class="hint">下一页<span class="arrow end"></span></div><div class="link">FROM&JOIN子句<!----></div></a></nav><!----><!----><!--]--></main><!--]--><footer class="site-footer"><span id="doc-version" style="display:none;">latest-Table</span><p class="copyright-text">版权所有 © 2026 Apache软件基金会。 |
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