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aria-label="print icon"><path d="M819.2 364.8h-44.8V128c0-17.067-14.933-32-32-32H281.6c-17.067 0-32 14.933-32 32v236.8h-44.8C145.067 364.8 96 413.867 96 473.6v192c0 59.733 49.067 108.8 108.8 108.8h44.8V896c0 17.067 14.933 32 32 32h460.8c17.067 0 32-14.933 32-32V774.4h44.8c59.733 0 108.8-49.067 108.8-108.8v-192c0-59.733-49.067-108.8-108.8-108.8zM313.6 160h396.8v204.8H313.6V160zm396.8 704H313.6V620.8h396.8V864zM864 665.6c0 25.6-19.2 44.8-44.8 44.8h-44.8V588.8c0-17.067-14.933-32-32-32H281.6c-17.067 0-32 14.933-32 32v121.6h-44.8c-25.6 0-44.8-19.2-44.8-44.8v-192c0-25.6 19.2-44.8 44.8-44.8h614.4c25.6 0 44.8 19.2 44.8 44.8v192z"></path></svg></button><div class="arrow end"></div></div><div class="vp-toc-wrapper"><ul class="vp-toc-list"><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level2" href="#字面值常量">字面值常量</a></li><li><ul class="vp-toc-list"><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#字符串常量">字符串常量</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#数值型常量">数值型常量</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#时间戳常量">时间戳常量</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#布尔型常量">布尔型常量</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#空值">空值</a></li><!----><!--]--></ul></li><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level2" href="#标识符">标识符</a></li><li><ul class="vp-toc-list"><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#使用场景-1">使用场景</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#约束">约束</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#如何在反引号引起的标识符中使用引号">如何在反引号引起的标识符中使用引号</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#特殊情况示例">特殊情况示例</a></li><!----><!--]--></ul></li><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level2" href="#关键字">关键字</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level2" href="#词法与文法详细定义">词法与文法详细定义</a></li><!----><!--]--></ul><div class="vp-toc-marker" style="top:-1.7rem;"></div></div><!--[--><!----><!--]--></aside></div><!--[--><!----><!--]--><div class="theme-hope-content"><h1 id="语法约定" tabindex="-1"><a class="header-anchor" href="#语法约定"><span>语法约定</span></a></h1><h2 id="字面值常量" tabindex="-1"><a class="header-anchor" href="#字面值常量"><span>字面值常量</span></a></h2><p>该部分对 IoTDB 中支持的字面值常量进行说明，包括字符串常量、数值型常量、时间戳常量、布尔型常量和空值。</p><h3 id="字符串常量" tabindex="-1"><a class="header-anchor" href="#字符串常量"><span>字符串常量</span></a></h3><p>在 IoTDB 中，字符串是由<strong>单引号（<code>&#39;</code>）或双引号（<code>&quot;</code>）字符括起来的字符序列</strong>。示例如下：</p><div class="language-Plain%20Text line-numbers-mode" data-ext="Plain%20Text" data-title="Plain%20Text"><pre class="language-Plain%20Text"><code>&#39;a string&#39;
&quot;another string&quot;
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div></div></div><h4 id="使用场景" tabindex="-1"><a class="header-anchor" href="#使用场景"><span>使用场景</span></a></h4><ul><li><p><code>INSERT</code> 或者 <code>SELECT</code> 中用于表达 <code>TEXT</code> 类型数据的场景。</p><div class="language-SQL line-numbers-mode" data-ext="SQL" data-title="SQL"><pre class="language-SQL"><code># insert 示例
insert into root.ln.wf02.wt02(timestamp,hardware) values(1, &#39;v1&#39;)
insert into root.ln.wf02.wt02(timestamp,hardware) values(2, &#39;\\&#39;)

+-----------------------------+--------------------------+
|                         Time|root.ln.wf02.wt02.hardware|
+-----------------------------+--------------------------+
|1970-01-01T08:00:00.001+08:00|                        v1|
+-----------------------------+--------------------------+
|1970-01-01T08:00:00.002+08:00|                        \\|
+-----------------------------+--------------------------+

# select 示例
select code from root.sg1.d1 where code in (&#39;string1&#39;, &#39;string2&#39;);
</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></div></li><li><p><code>LOAD</code> / <code>REMOVE</code> / <code>SETTLE</code> 指令中的文件路径。</p><div class="language-SQL line-numbers-mode" data-ext="SQL" data-title="SQL"><pre class="language-SQL"><code># load 示例
LOAD &#39;examplePath&#39;

# remove 示例
REMOVE &#39;examplePath&#39;

# SETTLE 示例
SETTLE &#39;examplePath&#39;
</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></div></li><li><p>用户密码。</p><div class="language-SQL line-numbers-mode" data-ext="SQL" data-title="SQL"><pre class="language-SQL"><code># 示例，write_pwd 即为用户密码
CREATE USER ln_write_user &#39;write_pwd&#39;
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div></div></div></li><li><p>触发器和 UDF 中的类全类名，示例如下：</p><div class="language-SQL line-numbers-mode" data-ext="SQL" data-title="SQL"><pre class="language-SQL"><code># 触发器示例，AS 后使用字符串表示类全类名
CREATE TRIGGER `alert-listener-sg1d1s1`
AFTER INSERT
ON root.sg1.d1.s1
AS &#39;org.apache.iotdb.db.engine.trigger.example.AlertListener&#39;
WITH (
  &#39;lo&#39; = &#39;0&#39;, 
  &#39;hi&#39; = &#39;100.0&#39;
)

# UDF 示例，AS 后使用字符串表示类全类名
CREATE FUNCTION example AS &#39;org.apache.iotdb.udf.UDTFExample&#39;
</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></div></li><li><p>Select 子句中可以为结果集中的值指定别名，别名可以被定义为字符串或者标识符，示例如下：</p><div class="language-SQL line-numbers-mode" data-ext="SQL" data-title="SQL"><pre class="language-SQL"><code>select s1 as &#39;temperature&#39;, s2 as &#39;speed&#39; from root.ln.wf01.wt01;

# 表头如下所示
+-----------------------------+-----------|-----+
|                         Time|temperature|speed|
+-----------------------------+-----------|-----+
</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></li><li><p>用于表示键值对，键值对的键和值可以被定义成常量（包括字符串）或者标识符，具体请参考键值对章节。</p></li></ul><h4 id="如何在字符串内使用引号" tabindex="-1"><a class="header-anchor" href="#如何在字符串内使用引号"><span>如何在字符串内使用引号</span></a></h4><ul><li>在单引号引起的字符串内，双引号无需特殊处理。同理，在双引号引起的字符串内，单引号无需特殊处理。</li><li>在单引号引起的字符串里，可以通过双写单引号来表示一个单引号，即单引号 &#39; 可以表示为 &#39;&#39;。</li><li>在双引号引起的字符串里，可以通过双写双引号来表示一个双引号，即双引号 &quot; 可以表示为 &quot;&quot;。</li></ul><p>字符串内使用引号的示例如下：</p><div class="language-Plain%20Text line-numbers-mode" data-ext="Plain%20Text" data-title="Plain%20Text"><pre class="language-Plain%20Text"><code>&#39;string&#39;  // string
&#39;&quot;string&quot;&#39;  // &quot;string&quot;
&#39;&quot;&quot;string&quot;&quot;&#39;  // &quot;&quot;string&quot;&quot;
&#39;&#39;&#39;string&#39;  // &#39;string

&quot;string&quot; // string
&quot;&#39;string&#39;&quot;  // &#39;string&#39;
&quot;&#39;&#39;string&#39;&#39;&quot;  // &#39;&#39;string&#39;&#39;
&quot;&quot;&quot;string&quot;  // &quot;string
</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></div><h3 id="数值型常量" tabindex="-1"><a class="header-anchor" href="#数值型常量"><span>数值型常量</span></a></h3><p>数值型常量包括整型和浮点型。</p><p>整型常量是一个数字序列。可以以 <code>+</code> 或 <code>-</code> 开头表示正负。例如：<code>1</code>, <code>-1</code>。</p><p>带有小数部分或由科学计数法表示的为浮点型常量，例如：<code>.1</code>, <code>3.14</code>, <code>-2.23</code>, <code>+1.70</code>, <code>1.2E3</code>, <code>1.2E-3</code>, <code>-1.2E3</code>, <code>-1.2E-3</code>。</p><p>在 IoTDB 中，<code>INT32</code> 和 <code>INT64</code> 表示整数类型（计算是准确的），<code>FLOAT</code> 和 <code>DOUBLE</code> 表示浮点数类型（计算是近似的）。</p><p>在浮点上下文中可以使用整数，它会被解释为等效的浮点数。</p><h3 id="时间戳常量" tabindex="-1"><a class="header-anchor" href="#时间戳常量"><span>时间戳常量</span></a></h3><p>时间戳是一个数据到来的时间点，在 IoTDB 中分为绝对时间戳和相对时间戳。详细信息可参考 <a class="route-link" href="/zh/UserGuide/latest/Basic-Concept/Data-Type.html">数据类型文档</a>。</p><p>特别地，<code>NOW()</code>表示语句开始执行时的服务端系统时间戳。</p><h3 id="布尔型常量" tabindex="-1"><a class="header-anchor" href="#布尔型常量"><span>布尔型常量</span></a></h3><p>布尔值常量 <code>TRUE</code> 和 <code>FALSE</code> 分别等价于 <code>1</code> 和 <code>0</code>，它们对大小写不敏感。</p><h3 id="空值" tabindex="-1"><a class="header-anchor" href="#空值"><span>空值</span></a></h3><p><code>NULL</code>值表示没有数据。<code>NULL</code>对大小写不敏感。</p><h2 id="标识符" tabindex="-1"><a class="header-anchor" href="#标识符"><span>标识符</span></a></h2><h3 id="使用场景-1" tabindex="-1"><a class="header-anchor" href="#使用场景-1"><span>使用场景</span></a></h3><p>在 IoTDB 中，触发器名称、UDF函数名、元数据模板名称、用户与角色名、连续查询标识、Pipe、PipeSink、键值对中的键和值、别名等可以作为标识符。</p><h3 id="约束" tabindex="-1"><a class="header-anchor" href="#约束"><span>约束</span></a></h3><p>请注意，此处约束是标识符的通用约束，具体标识符可能还附带其它约束条件，如用户名限制字符数大于等于4，更严格的约束请参考具体标识符相关的说明文档。</p><p><strong>标识符命名有以下约束：</strong></p><ul><li><p>不使用反引号括起的标识符中，允许出现以下字符：</p><ul><li>[ 0-9 a-z A-Z _ ] （字母，数字，下划线）</li><li>[&#39;\u2E80&#39;..&#39;\u9FFF&#39;] （UNICODE 中文字符）</li></ul></li><li><p>标识符允许使用数字开头、不使用反引号括起的标识符不能全部为数字。</p></li><li><p>标识符是大小写敏感的。</p></li><li><p>标识符允许为关键字。</p></li></ul><p><strong>如果出现如下情况，标识符需要使用反引号进行引用：</strong></p><ul><li>标识符包含不允许的特殊字符。</li><li>标识符为实数。</li></ul><h3 id="如何在反引号引起的标识符中使用引号" tabindex="-1"><a class="header-anchor" href="#如何在反引号引起的标识符中使用引号"><span>如何在反引号引起的标识符中使用引号</span></a></h3><p><strong>在反引号引起的标识符中可以直接使用单引号和双引号。</strong></p><p><strong>在用反引号引用的标识符中，可以通过双写反引号的方式使用反引号，即 ` 可以表示为 ``</strong>，示例如下：</p><div class="language-SQL line-numbers-mode" data-ext="SQL" data-title="SQL"><pre class="language-SQL"><code># 创建模板 t1`t
create schema template `t1``t` 
(temperature FLOAT encoding=RLE, status BOOLEAN encoding=PLAIN compression=SNAPPY)

# 创建模板 t1&#39;t&quot;t
create schema template `t1&#39;t&quot;t` 
(temperature FLOAT encoding=RLE, status BOOLEAN encoding=PLAIN compression=SNAPPY)
</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></div><h3 id="特殊情况示例" tabindex="-1"><a class="header-anchor" href="#特殊情况示例"><span>特殊情况示例</span></a></h3><p>需要使用反引号进行引用的部分情况示例：</p><ul><li><p>触发器名称出现上述特殊情况时需使用反引号引用：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 创建触发器 alert.`listener-sg1d1s1</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TRIGGER</span> <span class="token identifier"><span class="token punctuation">`</span>alert.``listener-sg1d1s1<span class="token punctuation">`</span></span>
<span class="token keyword">AFTER</span> <span class="token keyword">INSERT</span>
<span class="token keyword">ON</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1<span class="token punctuation">.</span>s1
<span class="token keyword">AS</span> <span class="token string">&#39;org.apache.iotdb.db.engine.trigger.example.AlertListener&#39;</span>
<span class="token keyword">WITH</span> <span class="token punctuation">(</span>
  <span class="token string">&#39;lo&#39;</span> <span class="token operator">=</span> <span class="token string">&#39;0&#39;</span><span class="token punctuation">,</span> 
  <span class="token string">&#39;hi&#39;</span> <span class="token operator">=</span> <span class="token string">&#39;100.0&#39;</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 class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div></li><li><p>UDF 名称出现上述特殊情况时需使用反引号引用：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 创建名为 111 的 UDF，111 为实数，所以需要用反引号引用。</span>
<span class="token keyword">CREATE</span> <span class="token keyword">FUNCTION</span> <span class="token identifier"><span class="token punctuation">`</span>111<span class="token punctuation">`</span></span> <span class="token keyword">AS</span> <span class="token string">&#39;org.apache.iotdb.udf.UDTFExample&#39;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div></div></div></li><li><p>元数据模板名称出现上述特殊情况时需使用反引号引用：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 创建名为 111 的元数据模板，111 为实数，需要用反引号引用。</span>
<span class="token keyword">create</span> <span class="token keyword">schema</span> template <span class="token identifier"><span class="token punctuation">`</span>111<span class="token punctuation">`</span></span> 
<span class="token punctuation">(</span>temperature <span class="token keyword">FLOAT</span> encoding<span class="token operator">=</span>RLE<span class="token punctuation">,</span> <span class="token keyword">status</span> <span class="token keyword">BOOLEAN</span> encoding<span class="token operator">=</span>PLAIN compression<span class="token operator">=</span>SNAPPY<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></div></li><li><p>用户名、角色名出现上述特殊情况时需使用反引号引用，同时无论是否使用反引号引用，用户名、角色名中均不允许出现空格，具体请参考权限管理章节中的说明。</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 创建用户 special`user.</span>
<span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token identifier"><span class="token punctuation">`</span>special``user.<span class="token punctuation">`</span></span> <span class="token string">&#39;write_pwd&#39;</span>

<span class="token comment"># 创建角色 111</span>
<span class="token keyword">CREATE</span> ROLE <span class="token identifier"><span class="token punctuation">`</span>111<span class="token punctuation">`</span></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></li><li><p>连续查询标识出现上述特殊情况时需使用反引号引用：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token comment"># 创建连续查询 test.cq</span>
<span class="token keyword">CREATE</span> CONTINUOUS QUERY <span class="token identifier"><span class="token punctuation">`</span>test.cq<span class="token punctuation">`</span></span> 
<span class="token keyword">BEGIN</span> 
  <span class="token keyword">SELECT</span> max_value<span class="token punctuation">(</span>temperature<span class="token punctuation">)</span> 
  <span class="token keyword">INTO</span> temperature_max 
  <span class="token keyword">FROM</span> root<span class="token punctuation">.</span>ln<span class="token punctuation">.</span><span class="token operator">*</span><span class="token punctuation">.</span><span class="token operator">*</span> 
  <span class="token keyword">GROUP</span> <span class="token keyword">BY</span> <span class="token keyword">time</span><span class="token punctuation">(</span><span class="token number">10</span>s<span class="token punctuation">)</span> 
<span class="token keyword">END</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></div></li><li><p>Pipe、PipeSink 名称出现上述特殊情况时需使用反引号引用：</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 PipeSink test.*1</span>
<span class="token keyword">CREATE</span> PIPESINK <span class="token identifier"><span class="token punctuation">`</span>test.*1<span class="token punctuation">`</span></span> <span class="token keyword">AS</span> IoTDB <span class="token punctuation">(</span><span class="token string">&#39;ip&#39;</span> <span class="token operator">=</span> <span class="token string">&#39;输入你的IP&#39;</span><span class="token punctuation">)</span>

<span class="token comment"># 创建 Pipe test.*2</span>
<span class="token keyword">CREATE</span> PIPE <span class="token identifier"><span class="token punctuation">`</span>test.*2<span class="token punctuation">`</span></span> <span class="token keyword">TO</span> <span class="token identifier"><span class="token punctuation">`</span>test.*1<span class="token punctuation">`</span></span> <span class="token keyword">FROM</span> 
<span class="token punctuation">(</span><span class="token keyword">select</span> <span class="token operator">*</span><span class="token operator">*</span> <span class="token keyword">from</span> root <span class="token keyword">WHERE</span> <span class="token keyword">time</span><span class="token operator">&gt;=</span>yyyy<span class="token operator">-</span>mm<span class="token operator">-</span>dd HH:MM:SS<span class="token punctuation">)</span> <span class="token keyword">WITH</span> <span class="token string">&#39;SyncDelOp&#39;</span> <span class="token operator">=</span> <span class="token string">&#39;true&#39;</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></li><li><p>Select 子句中可以结果集中的值指定别名，别名可以被定义为字符串或者标识符，示例如下：</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token keyword">select</span> s1 <span class="token keyword">as</span> temperature<span class="token punctuation">,</span> s2 <span class="token keyword">as</span> speed <span class="token keyword">from</span> root<span class="token punctuation">.</span>ln<span class="token punctuation">.</span>wf01<span class="token punctuation">.</span>wt01<span class="token punctuation">;</span>
<span class="token comment"># 表头如下所示</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>temperature<span class="token operator">|</span>speed<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></div></li><li><p>用于表示键值对，键值对的键和值可以被定义成常量（包括字符串）或者标识符，具体请参考键值对章节。</p></li><li><p>路径中非database的节点允许含有“<em>”符号，在使用时需要把该节点用反引号括起来，如root.db.<code>*</code>，但是此种用法只建议在路径中不可避免含有“</em>”时使用。</p></li></ul><h2 id="关键字" tabindex="-1"><a class="header-anchor" href="#关键字"><span>关键字</span></a></h2><p>关键字是在 SQL 具有特定含义的词，可以作为标识符。保留字是关键字的一个子集，保留字不能用于标识符。</p><p>关于 IoTDB 的关键字列表，可以查看 <a class="route-link" href="/zh/UserGuide/latest/Reference/Keywords.html">关键字</a> 。</p><h2 id="词法与文法详细定义" tabindex="-1"><a class="header-anchor" href="#词法与文法详细定义"><span>词法与文法详细定义</span></a></h2><p>请阅读代码仓库中的词法和语法描述文件：</p><p>词法文件：<code>antlr/src/main/antlr4/org/apache/iotdb/db/qp/sql/IoTDBSqlLexer.g4</code></p><p>语法文件：<code>antlr/src/main/antlr4/org/apache/iotdb/db/qp/sql/IoTDBSqlParser.g4</code></p></div><!--[--><!----><!--]--><footer class="vp-page-meta"><div class="vp-meta-item edit-link"><a href="https://github.com/apache/iotdb-docs/edit/main/src/zh/UserGuide/latest/User-Manual/Syntax-Rule.md" rel="noopener noreferrer" target="_blank" aria-label="发现错误？在 GitHub 上编辑此页" class="nav-link vp-meta-label"><!--[--><svg xmlns="http://www.w3.org/2000/svg" class="icon edit-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="edit icon"><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<span><svg class="external-link-icon" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path><polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg><span class="external-link-icon-sr-only">open in new window</span></span><!----></a></div><div class="vp-meta-item git-info"><div class="update-time"><span class="vp-meta-label">上次编辑于: </span><!----></div><!----></div></footer><nav class="vp-page-nav"><!----><a class="route-link nav-link next" href="/zh/UserGuide/latest/User-Manual/Operate-Metadata.html" aria-label="元数据管理"><div class="hint">下一页<span class="arrow end"></span></div><div class="link">元数据管理<!----></div></a></nav><!----><!--[--><!----><!--]--><!--]--></main><!--]--><footer style="padding-bottom:2rem;"><span id="doc-version" style="display:none;">latest</span><p style="text-align:center;color:#909399;font-size:12px;margin:0 30px;">Copyright © 2024 The Apache Software Foundation.<br> Apache and the Apache feather logo are trademarks of The Apache Software Foundation</p><p style="text-align:center;margin-top:10px;color:#909399;font-size:12px;margin:0 30px;"><strong>Have a question?</strong> Connect with us on QQ, WeChat, or Slack. <a href="https://github.com/apache/iotdb/issues/1995">Join the community</a> now.</p></footer></div><!--]--><!--]--><!--[--><!----><!--]--><!--]--></div>
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