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Defined Function)"><!---->UDF (User Defined Function)<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Aggregation.html" class="nav-link sidebar-link sidebar-page" aria-label="Aggregation"><!---->Aggregation<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Mathematical.html" class="nav-link sidebar-link sidebar-page" aria-label="Mathematical"><!---->Mathematical<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html" class="router-link-active router-link-exact-active nav-link active sidebar-link sidebar-page active" aria-label="Comparison"><!---->Comparison<!----></a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#basic-comparison-operators" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="Basic comparison operators"><!---->Basic comparison operators<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#between-and-operator" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="BETWEEN ... AND ... operator"><!---->BETWEEN ... AND ... operator<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#fuzzy-matching-operator" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="Fuzzy matching operator"><!---->Fuzzy matching operator<!----></a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#use-like-for-fuzzy-matching" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="Use Like for fuzzy matching"><!---->Use Like for fuzzy matching<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#use-regexp-for-fuzzy-matching" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="Use Regexp for fuzzy matching"><!---->Use Regexp for fuzzy matching<!----></a><ul class="sidebar-sub-headers"></ul></li></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#is-null-operator" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="IS NULL operator"><!---->IS NULL operator<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#in-operator" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="IN operator"><!---->IN operator<!----></a><ul class="sidebar-sub-headers"></ul></li><li class="sidebar-sub-header"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#condition-functions" class="router-link-active router-link-exact-active nav-link sidebar-link heading" aria-label="Condition Functions"><!---->Condition Functions<!----></a><ul class="sidebar-sub-headers"></ul></li></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Logical.html" class="nav-link sidebar-link sidebar-page" aria-label="Logical"><!---->Logical<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Conversion.html" class="nav-link sidebar-link sidebar-page" aria-label="Conversion"><!---->Conversion<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Constant.html" class="nav-link sidebar-link sidebar-page" aria-label="Constant"><!---->Constant<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Selection.html" class="nav-link sidebar-link sidebar-page" aria-label="Selection"><!---->Selection<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Continuous-Interval.html" class="nav-link sidebar-link sidebar-page" aria-label="Continuous Interval"><!---->Continuous Interval<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Variation-Trend.html" class="nav-link sidebar-link sidebar-page" aria-label="Variation Trend"><!---->Variation Trend<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Sample.html" class="nav-link sidebar-link sidebar-page" aria-label="Sample"><!---->Sample<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Time-Series.html" class="nav-link sidebar-link sidebar-page" aria-label="Time-Series"><!---->Time-Series<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Lambda.html" class="nav-link sidebar-link sidebar-page" aria-label="Lambda"><!---->Lambda<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Data-Profiling.html" class="nav-link sidebar-link sidebar-page" aria-label="Data Profiling"><!---->Data Profiling<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Anomaly-Detection.html" class="nav-link sidebar-link sidebar-page" aria-label="Anomaly Detection"><!---->Anomaly Detection<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Data-Matching.html" class="nav-link sidebar-link sidebar-page" aria-label="Data Matching"><!---->Data Matching<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Frequency-Domain.html" class="nav-link sidebar-link sidebar-page" aria-label="Frequency Domain"><!---->Frequency Domain<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Data-Quality.html" class="nav-link sidebar-link sidebar-page" aria-label="Data Quality"><!---->Data Quality<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Data-Repairing.html" class="nav-link sidebar-link sidebar-page" aria-label="Data Repairing"><!---->Data Repairing<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li><li><!--[--><a href="/UserGuide/V1.0.x/Operators-Functions/Series-Discovery.html" class="nav-link sidebar-link sidebar-page" aria-label="Series Discovery"><!---->Series Discovery<!----></a><ul class="sidebar-sub-headers"></ul><!--]--></li></ul></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Trigger</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Monitor and Alert</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Administration Management</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Maintenance Tools</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Collaboration of Edge and Cloud</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Ecosystem Integration</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Cluster</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">FAQ</span><span class="arrow end"></span></button><!----></section></li><li><section class="sidebar-group"><button class="sidebar-heading clickable"><!----><span class="title">Reference</span><span class="arrow end"></span></button><!----></section></li></ul><!--[--><!----><!--]--></aside><!--[--><main class="page" id="main-content"><!--[--><!----><nav class="breadcrumb disable"></nav><div class="page-title"><h1><!---->Comparison Operators and Functions</h1><div class="page-info"><!----><!----><!----><!----><span class="page-reading-time-info" aria-label="Reading Time"><svg xmlns="http://www.w3.org/2000/svg" class="icon timer-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="timer icon"><path d="M799.387 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id="toc"><!--[--><!----><!--]--><div class="toc-header">On This Page<button class="print-button" title="Print"><svg xmlns="http://www.w3.org/2000/svg" class="icon print-icon" viewBox="0 0 1024 1024" fill="currentColor" aria-label="print icon"><path d="M819.2 364.8h-44.8V128c0-17.067-14.933-32-32-32H281.6c-17.067 0-32 14.933-32 32v236.8h-44.8C145.067 364.8 96 413.867 96 473.6v192c0 59.733 49.067 108.8 108.8 108.8h44.8V896c0 17.067 14.933 32 32 32h460.8c17.067 0 32-14.933 32-32V774.4h44.8c59.733 0 108.8-49.067 108.8-108.8v-192c0-59.733-49.067-108.8-108.8-108.8zM313.6 160h396.8v204.8H313.6V160zm396.8 704H313.6V620.8h396.8V864zM864 665.6c0 25.6-19.2 44.8-44.8 44.8h-44.8V588.8c0-17.067-14.933-32-32-32H281.6c-17.067 0-32 14.933-32 32v121.6h-44.8c-25.6 0-44.8-19.2-44.8-44.8v-192c0-25.6 19.2-44.8 44.8-44.8h614.4c25.6 0 44.8 19.2 44.8 44.8v192z"></path></svg></button></div><div class="toc-wrapper"><ul class="toc-list"><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#basic-comparison-operators" class="router-link-active router-link-exact-active toc-link level2">Basic comparison operators</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#between-and-operator" class="router-link-active router-link-exact-active toc-link level2">BETWEEN ... AND ... operator</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#fuzzy-matching-operator" class="router-link-active router-link-exact-active toc-link level2">Fuzzy matching operator</a></li><ul class="toc-list"><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#use-like-for-fuzzy-matching" class="router-link-active router-link-exact-active toc-link level3">Use Like for fuzzy matching</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#use-regexp-for-fuzzy-matching" class="router-link-active router-link-exact-active toc-link level3">Use Regexp for fuzzy matching</a></li><!----><!--]--></ul><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#is-null-operator" class="router-link-active router-link-exact-active toc-link level2">IS NULL operator</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#in-operator" class="router-link-active router-link-exact-active toc-link level2">IN operator</a></li><!----><!--]--><!--[--><li class="toc-item"><a aria-current="page" href="/UserGuide/V1.0.x/Operators-Functions/Comparison.html#condition-functions" class="router-link-active router-link-exact-active toc-link level2">Condition Functions</a></li><!----><!--]--></ul></div><!--[--><!----><!--]--></aside></div><!----><div class="theme-hope-content"><!--

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--><h1 id="comparison-operators-and-functions" tabindex="-1"><a class="header-anchor" href="#comparison-operators-and-functions" aria-hidden="true">#</a> Comparison Operators and Functions</h1><h2 id="basic-comparison-operators" tabindex="-1"><a class="header-anchor" href="#basic-comparison-operators" aria-hidden="true">#</a> Basic comparison operators</h2><p>Supported operators <code>&gt;</code>, <code>&gt;=</code>, <code>&lt;</code>, <code>&lt;=</code>, <code>==</code>, <code>!=</code> (or <code>&lt;&gt;</code> )</p><p>Supported input data types: <code>INT32</code>, <code>INT64</code>, <code>FLOAT</code> and <code>DOUBLE</code></p><p>Note: It will transform all type to <code>DOUBLE</code> then do computation.</p><p>Output data type: <code>BOOLEAN</code></p><p><strong>Example:</strong></p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> a<span class="token punctuation">,</span> b<span class="token punctuation">,</span> a <span class="token operator">&gt;</span> <span class="token number">10</span><span class="token punctuation">,</span> a <span class="token operator">&lt;=</span> b<span class="token punctuation">,</span> <span class="token operator">!</span><span class="token punctuation">(</span>a <span class="token operator">&lt;=</span> b<span class="token punctuation">)</span><span class="token punctuation">,</span> a <span class="token operator">&gt;</span> <span class="token number">10</span> <span class="token operator">&amp;&amp;</span> a <span class="token operator">&gt;</span> b <span class="token keyword">from</span> root<span class="token punctuation">.</span>test<span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>IoTDB&gt; select a, b, a &gt; 10, a &lt;= b, !(a &lt;= b), a &gt; 10 &amp;&amp; a &gt; b from root.test;
+-----------------------------+-----------+-----------+----------------+--------------------------+---------------------------+------------------------------------------------+
|                         Time|root.test.a|root.test.b|root.test.a &gt; 10|root.test.a &lt;= root.test.b|!root.test.a &lt;= root.test.b|(root.test.a &gt; 10) &amp; (root.test.a &gt; root.test.b)|
+-----------------------------+-----------+-----------+----------------+--------------------------+---------------------------+------------------------------------------------+
|1970-01-01T08:00:00.001+08:00|         23|       10.0|            true|                     false|                       true|                                            true|
|1970-01-01T08:00:00.002+08:00|         33|       21.0|            true|                     false|                       true|                                            true|
|1970-01-01T08:00:00.004+08:00|         13|       15.0|            true|                      true|                      false|                                           false|
|1970-01-01T08:00:00.005+08:00|         26|        0.0|            true|                     false|                       true|                                            true|
|1970-01-01T08:00:00.008+08:00|          1|       22.0|           false|                      true|                      false|                                           false|
|1970-01-01T08:00:00.010+08:00|         23|       12.0|            true|                     false|                       true|                                            true|
+-----------------------------+-----------+-----------+----------------+--------------------------+---------------------------+------------------------------------------------+
</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></div><h2 id="between-and-operator" tabindex="-1"><a class="header-anchor" href="#between-and-operator" aria-hidden="true">#</a> <code>BETWEEN ... AND ...</code> operator</h2><table><thead><tr><th>operator</th><th>meaning</th></tr></thead><tbody><tr><td><code>BETWEEN ... AND ...</code></td><td>within the specified range</td></tr><tr><td><code>NOT BETWEEN ... AND ...</code></td><td>Not within the specified range</td></tr></tbody></table><p><strong>Example:</strong> Select data within or outside the interval [36.5,40]:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> temperature <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1 <span class="token keyword">where</span> temperature <span class="token operator">between</span> <span class="token number">36.5</span> <span class="token operator">and</span> <span class="token number">40</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> temperature <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1 <span class="token keyword">where</span> temperature <span class="token operator">not</span> <span class="token operator">between</span> <span class="token number">36.5</span> <span class="token operator">and</span> <span class="token number">40</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><h2 id="fuzzy-matching-operator" tabindex="-1"><a class="header-anchor" href="#fuzzy-matching-operator" aria-hidden="true">#</a> Fuzzy matching operator</h2><p>For TEXT type data, support fuzzy matching of data using <code>Like</code> and <code>Regexp</code> operators.</p><table><thead><tr><th>operator</th><th>meaning</th></tr></thead><tbody><tr><td><code>LIKE</code></td><td>matches simple patterns</td></tr><tr><td><code>NOT LIKE</code></td><td>cannot match simple pattern</td></tr><tr><td><code>REGEXP</code></td><td>Match regular expression</td></tr><tr><td><code>NOT REGEXP</code></td><td>Cannot match regular expression</td></tr></tbody></table><p>Input data type: <code>TEXT</code></p><p>Return type: <code>BOOLEAN</code></p><h3 id="use-like-for-fuzzy-matching" tabindex="-1"><a class="header-anchor" href="#use-like-for-fuzzy-matching" aria-hidden="true">#</a> Use <code>Like</code> for fuzzy matching</h3><p><strong>Matching rules:</strong></p><ul><li><code>%</code> means any 0 or more characters.</li><li><code>_</code> means any single character.</li></ul><p><strong>Example 1:</strong> Query the data under <code>root.sg.d1</code> that contains <code>&#39;cc&#39;</code> in <code>value</code>.</p><div class="language-bash line-numbers-mode" data-ext="sh"><pre class="language-bash"><code>IoTDB<span class="token operator">&gt;</span> <span class="token keyword">select</span> * from root.sg.d1 where value like <span class="token string">&#39;%cc%&#39;</span>
+--------------------------+----------------+
<span class="token operator">|</span> Time<span class="token operator">|</span>root.sg.d1.value<span class="token operator">|</span>
+--------------------------+----------------+
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:00.000+08:00<span class="token operator">|</span> aabbccdd<span class="token operator">|</span>
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:01.000+08:00<span class="token operator">|</span> cc<span class="token operator">|</span>
+--------------------------+----------------+
Total line number <span class="token operator">=</span> <span class="token number">2</span>
It costs <span class="token number">0</span>.002s
</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><p><strong>Example 2:</strong> Query the data under <code>root.sg.d1</code> with <code>&#39;b&#39;</code> in the middle of <code>value</code> and any single character before and after.</p><div class="language-bash line-numbers-mode" data-ext="sh"><pre class="language-bash"><code>IoTDB<span class="token operator">&gt;</span> <span class="token keyword">select</span> * from root.sg.device where value like <span class="token string">&#39;_b_&#39;</span>
+--------------------------+----------------+
<span class="token operator">|</span> Time<span class="token operator">|</span>root.sg.d1.value<span class="token operator">|</span>
+--------------------------+----------------+
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:02.000+08:00<span class="token operator">|</span>abc<span class="token operator">|</span>
+--------------------------+----------------+
Total line number <span class="token operator">=</span> <span class="token number">1</span>
It costs <span class="token number">0</span>.002s
</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><h3 id="use-regexp-for-fuzzy-matching" tabindex="-1"><a class="header-anchor" href="#use-regexp-for-fuzzy-matching" aria-hidden="true">#</a> Use <code>Regexp</code> for fuzzy matching</h3><p>The filter condition that needs to be passed in is <strong>Java standard library style regular expression</strong>.</p><p><strong>Common regular matching examples:</strong></p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>All characters with a length of 3-20: ^.{3,20}$
Uppercase English characters: ^[A-Z]+$
Numbers and English characters: ^[A-Za-z0-9]+$
Starting with a: ^a.*
</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></div><p><strong>Example 1:</strong> Query the string of 26 English characters for value under root.sg.d1.</p><div class="language-bash line-numbers-mode" data-ext="sh"><pre class="language-bash"><code>IoTDB<span class="token operator">&gt;</span> <span class="token keyword">select</span> * from root.sg.d1 where value regexp <span class="token string">&#39;^[A-Za-z]+$&#39;</span>
+--------------------------+----------------+
<span class="token operator">|</span> Time<span class="token operator">|</span>root.sg.d1.value<span class="token operator">|</span>
+--------------------------+----------------+
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:00.000+08:00<span class="token operator">|</span> aabbccdd<span class="token operator">|</span>
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:01.000+08:00<span class="token operator">|</span> cc<span class="token operator">|</span>
+--------------------------+----------------+
Total line number <span class="token operator">=</span> <span class="token number">2</span>
It costs <span class="token number">0</span>.002s
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><p><strong>Example 2:</strong> Query root.sg.d1 where the value is a string consisting of 26 lowercase English characters and the time is greater than 100.</p><div class="language-bash line-numbers-mode" data-ext="sh"><pre class="language-bash"><code>IoTDB<span class="token operator">&gt;</span> <span class="token keyword">select</span> * from root.sg.d1 where value regexp <span class="token string">&#39;^[a-z]+$&#39;</span> and <span class="token function">time</span> <span class="token operator">&gt;</span> <span class="token number">100</span>
+--------------------------+----------------+
<span class="token operator">|</span> Time<span class="token operator">|</span>root.sg.d1.value<span class="token operator">|</span>
+--------------------------+----------------+
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:00.000+08:00<span class="token operator">|</span> aabbccdd<span class="token operator">|</span>
<span class="token operator">|</span><span class="token number">2017</span>-11-01T00:00:01.000+08:00<span class="token operator">|</span> cc<span class="token operator">|</span>
+--------------------------+----------------+
Total line number <span class="token operator">=</span> <span class="token number">2</span>
It costs <span class="token number">0</span>.002s
</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><p><strong>Example 3:</strong></p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> b<span class="token punctuation">,</span> b <span class="token operator">like</span> <span class="token string">&#39;1%&#39;</span><span class="token punctuation">,</span> b <span class="token operator">regexp</span> <span class="token string">&#39;[0-2]&#39;</span> <span class="token keyword">from</span> root<span class="token punctuation">.</span>test<span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>operation result</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+-----------+------- ------------------+--------------------------+
| Time|root.test.b|root.test.b LIKE &#39;^1.*?$&#39;|root.test.b REGEXP &#39;[0-2]&#39;|
+-----------------------------+-----------+------- ------------------+--------------------------+
|1970-01-01T08:00:00.001+08:00| 111test111| true| true|
|1970-01-01T08:00:00.003+08:00| 333test333| false| false|
+-----------------------------+-----------+------- ------------------+--------------------------+
</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><h2 id="is-null-operator" tabindex="-1"><a class="header-anchor" href="#is-null-operator" aria-hidden="true">#</a> <code>IS NULL</code> operator</h2><table><thead><tr><th>operator</th><th>meaning</th></tr></thead><tbody><tr><td><code>IS NULL</code></td><td>is a null value</td></tr><tr><td><code>IS NOT NULL</code></td><td>is not a null value</td></tr></tbody></table><p><strong>Example 1:</strong> Select data with empty values:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> code <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1 <span class="token keyword">where</span> temperature <span class="token operator">is</span> <span class="token boolean">null</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p><strong>Example 2:</strong> Select data with non-null values:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> code <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1 <span class="token keyword">where</span> temperature <span class="token operator">is</span> <span class="token operator">not</span> <span class="token boolean">null</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><h2 id="in-operator" tabindex="-1"><a class="header-anchor" href="#in-operator" aria-hidden="true">#</a> <code>IN</code> operator</h2><table><thead><tr><th>operator</th><th>meaning</th></tr></thead><tbody><tr><td><code>IN</code> / <code>CONTAINS</code></td><td>are the values ​​in the specified list</td></tr><tr><td><code>NOT IN</code> / <code>NOT CONTAINS</code></td><td>not a value in the specified list</td></tr></tbody></table><p>Input data type: <code>All Types</code></p><p>return type <code>BOOLEAN</code></p><p>**Note: Please ensure that the values ​​in the collection can be converted to the type of the input data. **</p><blockquote><p>For example:</p><p><code>s1 in (1, 2, 3, &#39;test&#39;)</code>, the data type of <code>s1</code> is <code>INT32</code></p><p>We will throw an exception because <code>&#39;test&#39;</code> cannot be converted to type <code>INT32</code></p></blockquote><p><strong>Example 1:</strong> Select data with values ​​within a certain range:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> code <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1 <span class="token keyword">where</span> code <span class="token operator">in</span> <span class="token punctuation">(</span><span class="token string">&#39;200&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;300&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;400&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;500&#39;</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></div><p><strong>Example 2:</strong> Select data with values ​​outside a certain range:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> code <span class="token keyword">from</span> root<span class="token punctuation">.</span>sg1<span class="token punctuation">.</span>d1 <span class="token keyword">where</span> code <span class="token operator">not</span> <span class="token operator">in</span> <span class="token punctuation">(</span><span class="token string">&#39;200&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;300&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;400&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;500&#39;</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></div><p><strong>Example 3:</strong></p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> a<span class="token punctuation">,</span> a <span class="token operator">in</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 keyword">from</span> root<span class="token punctuation">.</span>test<span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>Output 2:</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+-----------+------- -------------+
| Time|root.test.a|root.test.a IN (1,2)|
+-----------------------------+-----------+------- -------------+
|1970-01-01T08:00:00.001+08:00| 1| true|
|1970-01-01T08:00:00.003+08:00| 3| false|
+-----------------------------+-----------+------- -------------+
</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><h2 id="condition-functions" tabindex="-1"><a class="header-anchor" href="#condition-functions" aria-hidden="true">#</a> Condition Functions</h2><p>Condition functions are used to check whether timeseries data points satisfy some specific condition.</p><p>They return BOOLEANs.</p><p>Currently, IoTDB supports the following condition functions:</p><table><thead><tr><th>Function Name</th><th>Allowed Input Series Data Types</th><th>Required Attributes</th><th>Output Series Data Type</th><th>Series Data Type Description</th></tr></thead><tbody><tr><td>ON_OFF</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>threshold</code>: a double type variate</td><td>BOOLEAN</td><td>Return <code>ts_value &gt;= threshold</code>.</td></tr><tr><td>IN_RANGR</td><td>INT32 / INT64 / FLOAT / DOUBLE</td><td><code>lower</code>: DOUBLE type<br><code>upper</code>: DOUBLE type</td><td>BOOLEAN</td><td>Return <code>ts_value &gt;= lower &amp;&amp; value &lt;= upper</code>.</td></tr></tbody></table><p>Example Data:</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>IoTDB&gt; select ts from root.test;
+-----------------------------+------------+
|                         Time|root.test.ts|
+-----------------------------+------------+
|1970-01-01T08:00:00.001+08:00|           1|
|1970-01-01T08:00:00.002+08:00|           2|
|1970-01-01T08:00:00.003+08:00|           3|
|1970-01-01T08:00:00.004+08:00|           4|
+-----------------------------+------------+
</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><h5 id="test-1" tabindex="-1"><a class="header-anchor" href="#test-1" aria-hidden="true">#</a> Test 1</h5><p>SQL:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> ts<span class="token punctuation">,</span> on_off<span class="token punctuation">(</span>ts<span class="token punctuation">,</span> <span class="token string">&#39;threshold&#39;</span><span class="token operator">=</span><span class="token string">&#39;2&#39;</span><span class="token punctuation">)</span> <span class="token keyword">from</span> root<span class="token punctuation">.</span>test<span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>Output:</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>IoTDB&gt; select ts, on_off(ts, &#39;threshold&#39;=&#39;2&#39;) from root.test;
+-----------------------------+------------+-------------------------------------+
|                         Time|root.test.ts|on_off(root.test.ts, &quot;threshold&quot;=&quot;2&quot;)|
+-----------------------------+------------+-------------------------------------+
|1970-01-01T08:00:00.001+08:00|           1|                                false|
|1970-01-01T08:00:00.002+08:00|           2|                                 true|
|1970-01-01T08:00:00.003+08:00|           3|                                 true|
|1970-01-01T08:00:00.004+08:00|           4|                                 true|
+-----------------------------+------------+-------------------------------------+
</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><h5 id="test-2" tabindex="-1"><a class="header-anchor" href="#test-2" aria-hidden="true">#</a> Test 2</h5><p>Sql:</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> ts<span class="token punctuation">,</span> in_range<span class="token punctuation">(</span>ts<span class="token punctuation">,</span> <span class="token string">&#39;lower&#39;</span><span class="token operator">=</span><span class="token string">&#39;2&#39;</span><span class="token punctuation">,</span> <span class="token string">&#39;upper&#39;</span><span class="token operator">=</span><span class="token string">&#39;3.1&#39;</span><span class="token punctuation">)</span> <span class="token keyword">from</span> root<span class="token punctuation">.</span>test<span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>Output:</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>IoTDB&gt; select ts, in_range(ts,&#39;lower&#39;=&#39;2&#39;, &#39;upper&#39;=&#39;3.1&#39;) from root.test;
+-----------------------------+------------+--------------------------------------------------+
|                         Time|root.test.ts|in_range(root.test.ts, &quot;lower&quot;=&quot;2&quot;, &quot;upper&quot;=&quot;3.1&quot;)|
+-----------------------------+------------+--------------------------------------------------+
|1970-01-01T08:00:00.001+08:00|           1|                                             false|
|1970-01-01T08:00:00.002+08:00|           2|                                              true|
|1970-01-01T08:00:00.003+08:00|           3|                                              true|
|1970-01-01T08:00:00.004+08:00|           4|                                             false|
+-----------------------------+------------+--------------------------------------------------+
</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></div><!----><footer class="page-meta"><div class="meta-item edit-link"><a href="https://github.com/apache/iotdb/edit/rel/1.0/docs/UserGuide/Operators-Functions/Comparison.md" rel="noopener noreferrer" target="_blank" aria-label="Found Error? Edit this page on GitHub" class="nav-link 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><!--]-->Found Error? Edit this page on GitHub<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="meta-item git-info"><!----><!----></div></footer><nav class="page-nav"><a href="/UserGuide/V1.0.x/Operators-Functions/Mathematical.html" class="nav-link prev" aria-label="Mathematical"><div class="hint"><span class="arrow start"></span>Prev</div><div class="link"><!---->Mathematical</div></a><a href="/UserGuide/V1.0.x/Operators-Functions/Logical.html" class="nav-link next" aria-label="Logical"><div class="hint">Next<span class="arrow end"></span></div><div class="link">Logical<!----></div></a></nav><!----><!----><!--]--></main><!--]--><footer style="padding-bottom:2rem;"><span id="doc-version" style="display:none;">rel/1.0</span><p style="text-align:center;color:#909399;font-size:12px;margin:0 30px;">Copyright © 2023 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><p style="text-align:center;margin-top:10px;color:#909399;font-size:12px;margin:0 30px;"> We use <a href="https://analytics.google.com">Google Analytics</a> to collect anonymous, aggregated usage information. </p></footer></div><!--]--><!--]--><!----><!--]--></div>
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