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import{_ as s,o as n,c as a,e}from"./app-Bp5kEZWW.js";const o={},t=e(`<h1 id="路径结点名" tabindex="-1"><a class="header-anchor" href="#路径结点名"><span>路径结点名</span></a></h1><p>路径结点名是特殊的标识符，其还可以是通配符 * 或 **。在创建时间序列时，各层级的路径结点名不能为通配符 * 或 **。在查询语句中，可以用通配符 * 或 ** 来表示路径结点名，以匹配一层或多层路径。</p><h2 id="通配符" tabindex="-1"><a class="header-anchor" href="#通配符"><span>通配符</span></a></h2><p><code>*</code>在路径中表示一层。例如<code>root.vehicle.*.sensor1</code>代表的是以<code>root.vehicle</code>为前缀，以<code>sensor1</code>为后缀，层次等于 4 层的路径。</p><p><code>**</code>在路径中表示是（<code>*</code>）+，即为一层或多层<code>*</code>。例如<code>root.vehicle.device1.**</code>代表的是<code>root.vehicle.device1.*</code>, <code>root.vehicle.device1.*.*</code>, <code>root.vehicle.device1.*.*.*</code>等所有以<code>root.vehicle.device1</code>为前缀路径的大于等于 4 层的路径；<code>root.vehicle.**.sensor1</code>代表的是以<code>root.vehicle</code>为前缀，以<code>sensor1</code>为后缀，层次大于等于 4 层的路径。</p><p>由于通配符 * 在查询表达式中也可以表示乘法符号，下述例子用于帮助您区分两种情况：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 创建时间序列 root.sg.\`a*b\`</span>
<span class="token keyword">create</span> timeseries root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>a*b<span class="token punctuation">\`</span></span> <span class="token keyword">with</span> datatype<span class="token operator">=</span><span class="token keyword">FLOAT</span><span class="token punctuation">,</span>encoding<span class="token operator">=</span>PLAIN<span class="token punctuation">;</span>
<span class="token comment"># 请注意，如标识符部分所述，a*b包含特殊字符，需要用\`\`括起来使用</span>
<span class="token comment"># create timeseries root.sg.a*b with datatype=FLOAT,encoding=PLAIN 是错误用法</span>
<span class="token comment"># 创建时间序列 root.sg.a</span>
<span class="token keyword">create</span> timeseries root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span>a <span class="token keyword">with</span> datatype<span class="token operator">=</span><span class="token keyword">FLOAT</span><span class="token punctuation">,</span>encoding<span class="token operator">=</span>PLAIN<span class="token punctuation">;</span>
<span class="token comment"># 创建时间序列 root.sg.b</span>
<span class="token keyword">create</span> timeseries root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span>b <span class="token keyword">with</span> datatype<span class="token operator">=</span><span class="token keyword">FLOAT</span><span class="token punctuation">,</span>encoding<span class="token operator">=</span>PLAIN<span class="token punctuation">;</span>
<span class="token comment"># 查询时间序列 root.sg.\`a*b\`</span>
<span class="token keyword">select</span> <span class="token identifier"><span class="token punctuation">\`</span>a*b<span class="token punctuation">\`</span></span> <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg
<span class="token comment"># 其结果集表头为</span>
<span class="token operator">|</span><span class="token keyword">Time</span><span class="token operator">|</span>root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span>a<span class="token operator">*</span>b<span class="token operator">|</span>
<span class="token comment"># 查询时间序列 root.sg.a 和 root.sg.b的乘积</span>
<span class="token keyword">select</span> a<span class="token operator">*</span>b <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg
<span class="token comment"># 其结果集表头为</span>
<span class="token operator">|</span><span class="token keyword">Time</span><span class="token operator">|</span>root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span>a <span class="token operator">*</span> root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span>b<span class="token operator">|</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div 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="标识符" tabindex="-1"><a class="header-anchor" href="#标识符"><span>标识符</span></a></h2><p>路径结点名不为通配符时，使用方法和标识符一致。<strong>在 SQL 中需要使用反引号引用的路径结点，在结果集中也会用反引号引起。</strong></p><p>需要使用反引号进行引用的部分特殊情况示例：</p><ul><li>创建时间序列时，如下情况需要使用反引号对特殊节点名进行引用：</li></ul><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 路径结点名中包含特殊字符，时间序列各结点为[&quot;root&quot;,&quot;sg&quot;,&quot;www.\`baidu.com&quot;]</span>
<span class="token keyword">create</span> timeseries root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>www.\`\`baidu.com<span class="token punctuation">\`</span></span><span class="token punctuation">.</span>a <span class="token keyword">with</span> datatype<span class="token operator">=</span><span class="token keyword">FLOAT</span><span class="token punctuation">,</span>encoding<span class="token operator">=</span>PLAIN<span class="token punctuation">;</span>
<span class="token comment"># 路径结点名为实数</span>
<span class="token keyword">create</span> timeseries root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>111<span class="token punctuation">\`</span></span> <span class="token keyword">with</span> datatype<span class="token operator">=</span><span class="token keyword">FLOAT</span><span class="token punctuation">,</span>encoding<span class="token operator">=</span>PLAIN<span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>依次执行示例中语句后，执行 show timeseries，结果如下：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token operator">+</span><span class="token comment">---------------------------+-----+-------------+--------+--------+-----------+----+----------+</span>
<span class="token operator">|</span> timeseries<span class="token operator">|</span>alias<span class="token operator">|</span><span class="token keyword">database</span><span class="token operator">|</span>dataType<span class="token operator">|</span>encoding<span class="token operator">|</span>compression<span class="token operator">|</span>tags<span class="token operator">|</span>attributes<span class="token operator">|</span>
<span class="token operator">+</span><span class="token comment">---------------------------+-----+-------------+--------+--------+-----------+----+----------+</span>
<span class="token operator">|</span> root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>111<span class="token punctuation">\`</span></span><span class="token punctuation">.</span>a<span class="token operator">|</span> <span class="token boolean">null</span><span class="token operator">|</span> root<span class="token punctuation">.</span>sg<span class="token operator">|</span> <span class="token keyword">FLOAT</span><span class="token operator">|</span> PLAIN<span class="token operator">|</span> SNAPPY<span class="token operator">|</span><span class="token boolean">null</span><span class="token operator">|</span> <span class="token boolean">null</span><span class="token operator">|</span>
<span class="token operator">|</span>root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>www.\`\`baidu.com<span class="token punctuation">\`</span></span><span class="token punctuation">.</span>a<span class="token operator">|</span> <span class="token boolean">null</span><span class="token operator">|</span> root<span class="token punctuation">.</span>sg<span class="token operator">|</span> <span class="token keyword">FLOAT</span><span class="token operator">|</span> PLAIN<span class="token operator">|</span> SNAPPY<span class="token operator">|</span><span class="token boolean">null</span><span class="token operator">|</span> <span class="token boolean">null</span><span class="token operator">|</span>
<span class="token operator">+</span><span class="token comment">---------------------------+-----+-------------+--------+--------+-----------+----+----------+</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><ul><li>插入数据时，如下情况需要使用反引号对特殊节点名进行引用：</li></ul><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 路径结点名中包含特殊字符</span>
<span class="token keyword">insert</span> <span class="token keyword">into</span> root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>www.\`\`baidu.com<span class="token punctuation">\`</span></span><span class="token punctuation">(</span><span class="token keyword">timestamp</span><span class="token punctuation">,</span> a<span class="token punctuation">)</span> <span class="token keyword">values</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token comment"># 路径结点名为实数</span>
<span class="token keyword">insert</span> <span class="token keyword">into</span> root<span class="token punctuation">.</span>sg<span class="token punctuation">(</span><span class="token keyword">timestamp</span><span class="token punctuation">,</span> <span class="token identifier"><span class="token punctuation">\`</span>111<span class="token punctuation">\`</span></span><span class="token punctuation">)</span> <span class="token keyword">values</span> <span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><ul><li>查询数据时，如下情况需要使用反引号对特殊节点名进行引用：</li></ul><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 路径结点名中包含特殊字符</span>
<span class="token keyword">select</span> a <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>www.\`\`baidu.com<span class="token punctuation">\`</span></span><span class="token punctuation">;</span>
<span class="token comment"># 路径结点名为实数</span>
<span class="token keyword">select</span> <span class="token identifier"><span class="token punctuation">\`</span>111<span class="token punctuation">\`</span></span> <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p>结果集分别为：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># select a from root.sg.\`www.\`\`baidu.com\` 结果集</span>
<span class="token operator">+</span><span class="token comment">-----------------------------+---------------------------+</span>
<span class="token operator">|</span> <span class="token keyword">Time</span><span class="token operator">|</span>root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>www.\`\`baidu.com<span class="token punctuation">\`</span></span><span class="token punctuation">.</span>a<span class="token operator">|</span>
<span class="token operator">+</span><span class="token comment">-----------------------------+---------------------------+</span>
<span class="token operator">|</span><span class="token number">1970</span><span class="token operator">-</span><span class="token number">01</span><span class="token operator">-</span><span class="token number">01</span>T08:<span class="token number">00</span>:<span class="token number">00.001</span><span class="token operator">+</span><span class="token number">08</span>:<span class="token number">00</span><span class="token operator">|</span> <span class="token number">2.0</span><span class="token operator">|</span>
<span class="token operator">+</span><span class="token comment">-----------------------------+---------------------------+</span>
<span class="token comment"># select \`111\` from root.sg 结果集</span>
<span class="token operator">+</span><span class="token comment">-----------------------------+-------------+</span>
<span class="token operator">|</span> <span class="token keyword">Time</span><span class="token operator">|</span>root<span class="token punctuation">.</span>sg<span class="token punctuation">.</span><span class="token identifier"><span class="token punctuation">\`</span>111<span class="token punctuation">\`</span></span><span class="token operator">|</span>
<span class="token operator">+</span><span class="token comment">-----------------------------+-------------+</span>
<span class="token operator">|</span><span class="token number">1970</span><span class="token operator">-</span><span class="token number">01</span><span class="token operator">-</span><span class="token number">01</span>T08:<span class="token number">00</span>:<span class="token number">00.001</span><span class="token operator">+</span><span class="token number">08</span>:<span class="token number">00</span><span class="token operator">|</span> <span class="token number">2.0</span><span class="token operator">|</span>
<span class="token operator">+</span><span class="token comment">-----------------------------+-------------+</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div>`,20),p=[t];function c(l,i){return n(),a("div",null,p)}const d=s(o,[["render",c],["__file","NodeName-In-Path.html.vue"]]),u=JSON.parse('{"path":"/zh/UserGuide/V1.0.x/Syntax-Conventions/NodeName-In-Path.html","title":"路径结点名","lang":"zh-CN","frontmatter":{"description":"路径结点名 路径结点名是特殊的标识符，其还可以是通配符 * 或 **。在创建时间序列时，各层级的路径结点名不能为通配符 * 或 **。在查询语句中，可以用通配符 * 或 ** 来表示路径结点名，以匹配一层或多层路径。 通配符 *在路径中表示一层。例如root.vehicle.*.sensor1代表的是以root.vehicle为前缀，以sensor1为...","head":[["link",{"rel":"alternate","hreflang":"en-us","href":"https://iotdb.apache.org/UserGuide/V1.0.x/Syntax-Conventions/NodeName-In-Path.html"}],["meta",{"property":"og:url","content":"https://iotdb.apache.org/zh/UserGuide/V1.0.x/Syntax-Conventions/NodeName-In-Path.html"}],["meta",{"property":"og:site_name","content":"IoTDB Website"}],["meta",{"property":"og:title","content":"路径结点名"}],["meta",{"property":"og:description","content":"路径结点名 路径结点名是特殊的标识符，其还可以是通配符 * 或 **。在创建时间序列时，各层级的路径结点名不能为通配符 * 或 **。在查询语句中，可以用通配符 * 或 ** 来表示路径结点名，以匹配一层或多层路径。 通配符 *在路径中表示一层。例如root.vehicle.*.sensor1代表的是以root.vehicle为前缀，以sensor1为..."}],["meta",{"property":"og:type","content":"article"}],["meta",{"property":"og:locale","content":"zh-CN"}],["meta",{"property":"og:locale:alternate","content":"en-US"}],["meta",{"property":"og:updated_time","content":"2023-07-10T03:11:17.000Z"}],["meta",{"property":"article:modified_time","content":"2023-07-10T03:11:17.000Z"}],["script",{"type":"application/ld+json"},"{\\"@context\\":\\"https://schema.org\\",\\"@type\\":\\"Article\\",\\"headline\\":\\"路径结点名\\",\\"image\\":[\\"\\"],\\"dateModified\\":\\"2023-07-10T03:11:17.000Z\\",\\"author\\":[]}"]]},"headers":[{"level":2,"title":"通配符","slug":"通配符","link":"#通配符","children":[]},{"level":2,"title":"标识符","slug":"标识符","link":"#标识符","children":[]}],"git":{"createdTime":1688958677000,"updatedTime":1688958677000,"contributors":[{"name":"CritasWang","email":"critas@outlook.com","commits":1}]},"readingTime":{"minutes":2.86,"words":857},"filePathRelative":"zh/UserGuide/V1.0.x/Syntax-Conventions/NodeName-In-Path.md","localizedDate":"2023年7月10日","autoDesc":true}');export{d as comp,u as data};