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class="vp-toc-placeholder"><aside id="toc"><!--[--><!----><!--]--><div class="vp-toc-header">On This Page<button type="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 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="#syntax-definition">Syntax Definition</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level2" href="#basic-examples">Basic Examples</a></li><li><ul class="vp-toc-list"><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#select-a-column-of-data-based-on-a-time-interval">Select a Column of Data Based on a Time Interval</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#select-multiple-columns-of-data-based-on-a-time-interval">Select Multiple Columns of Data Based on a Time Interval</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#select-multiple-columns-of-data-for-the-same-device-according-to-multiple-time-intervals">Select Multiple Columns of Data for the Same Device According to Multiple Time Intervals</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#choose-multiple-columns-of-data-for-different-devices-according-to-multiple-time-intervals">Choose Multiple Columns of Data for Different Devices According to Multiple Time Intervals</a></li><!----><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level3" href="#order-by-time-query">Order By Time Query</a></li><!----><!--]--></ul></li><!--]--><!--[--><li class="vp-toc-item"><a class="route-link vp-toc-link level2" href="#usage-in-different-clients">Usage in Different Clients</a></li><!----><!--]--></ul><div class="vp-toc-marker" style="top:-1.7rem;"></div></div><!--[--><!----><!--]--></aside></div><!--[--><!----><!--]--><div class="theme-hope-content"><h1 id="overview" tabindex="-1"><a class="header-anchor" href="#overview"><span>Overview</span></a></h1><h2 id="syntax-definition" tabindex="-1"><a class="header-anchor" href="#syntax-definition"><span>Syntax Definition</span></a></h2><p>In IoTDB, <code>SELECT</code> statement is used to retrieve data from one or more selected time series. Here is the syntax definition of <code>SELECT</code> statement:</p><div class="language-sql line-numbers-mode" data-ext="sql" data-title="sql"><pre class="language-sql"><code><span class="token punctuation">[</span>TRACING?<span class="token punctuation">]</span> <span class="token keyword">SELECT</span> 
	<span class="token punctuation">[</span><span class="token keyword">LAST</span>?<span class="token punctuation">]</span> selectExpr <span class="token punctuation">(</span><span class="token punctuation">,</span> selectExpr<span class="token punctuation">)</span><span class="token operator">*</span>
	<span class="token operator">&lt;</span>fromClause<span class="token operator">&gt;</span> <span class="token keyword">FROM</span> prefixPath <span class="token punctuation">(</span><span class="token punctuation">,</span> prefixPath<span class="token punctuation">)</span><span class="token operator">*</span>
	<span class="token operator">&lt;</span>whereClause?<span class="token operator">&gt;</span> <span class="token keyword">WHERE</span> queryFilter
	<span class="token operator">&lt;</span>orderByTimeClause?<span class="token operator">&gt;</span> <span class="token keyword">ORDER</span> <span class="token keyword">BY</span> <span class="token keyword">TIME</span> <span class="token punctuation">[</span><span class="token keyword">ASC</span> <span class="token operator">|</span> <span class="token keyword">DESC</span><span class="token punctuation">]</span>
	<span class="token operator">&lt;</span>paginationClause?<span class="token operator">&gt;</span> <span class="token punctuation">[</span><span class="token keyword">LIMIT</span> <span class="token operator">|</span> SLIMIT<span class="token punctuation">]</span> <span class="token keyword">INT</span> <span class="token punctuation">[</span><span class="token keyword">OFFSET</span> <span class="token operator">|</span> SOFFSET<span class="token punctuation">]</span> <span class="token keyword">INT</span>
	<span class="token operator">&lt;</span>groupByLevelClause?<span class="token operator">&gt;</span> <span class="token keyword">GROUP</span> <span class="token keyword">BY</span> <span class="token keyword">LEVEL</span> <span class="token operator">=</span> <span class="token keyword">INT</span>
	<span class="token operator">&lt;</span>groupByTimeClause?<span class="token operator">&gt;</span> <span class="token keyword">GROUP</span> <span class="token keyword">BY</span> <span class="token punctuation">(</span><span class="token punctuation">[</span>startTime<span class="token punctuation">,</span> endTime<span class="token punctuation">)</span><span class="token punctuation">,</span> slidingStep<span class="token punctuation">)</span>
	<span class="token operator">&lt;</span>fillClause?<span class="token operator">&gt;</span> FILL <span class="token punctuation">(</span><span class="token punctuation">[</span>PREVIOUS<span class="token punctuation">,</span> beforeRange <span class="token operator">|</span> LINEAR<span class="token punctuation">,</span> beforeRange<span class="token punctuation">,</span> afterRange <span class="token operator">|</span> constant<span class="token punctuation">]</span><span class="token punctuation">)</span>
	<span class="token operator">&lt;</span>withoutNullClause?<span class="token operator">&gt;</span> WITHOUT <span class="token boolean">NULL</span> <span class="token punctuation">[</span><span class="token keyword">ANY</span> <span class="token operator">|</span> <span class="token keyword">ALL</span><span class="token punctuation">]</span>
	<span class="token operator">&lt;</span>alignClause?<span class="token operator">&gt;</span> <span class="token punctuation">[</span>ALIGN <span class="token keyword">BY</span> DEVICE <span class="token operator">|</span> <span class="token keyword">DISABLE</span> ALIGN<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 class="line-number"></div><div class="line-number"></div></div></div><p>The most commonly used clauses of <code>SELECT</code> statements are these:</p><ul><li>Each <code>selectExpr</code> indicates a column that you want to retrieve, which may be a suffix of time series paths, an aggregate function and so on. There must be at least one <code>selectExpr</code>. For more details for <code>selectExpr</code>, please refer to <a class="route-link" href="/UserGuide/V0.13.x/Query-Data/Select-Expression.html">Select Expression</a> .</li><li><code>fromClause</code> contains the prefix of one or more time-series paths to query.</li><li><code>whereClause</code> (Optional) specify the filter criterion named <code> queryfilter</code>. <code>queryfilter</code> is a logical expression that returns the data points which calculation result is TRUE. If you do not specify <code>whereClause</code>, return all data points in the time series. For more details, please refer to <a class="route-link" href="/UserGuide/V0.13.x/Query-Data/Query-Filter.html">Query Filter</a>.</li><li>The query results are sorted in ascending order by timestamp. You can specify the results to be sorted in descending order by timestamp through <code>ORDER BY TIME DESC</code> clause.</li><li>When there is a large amount of query result data, you can use <code>LIMIT/SLIMIT</code> and <code>OFFSET/SOFFSET</code> to paginate the result set, see <a class="route-link" href="/UserGuide/V0.13.x/Query-Data/Pagination.html">Query Result Pagination</a> for details.</li><li>The query result set is aligned according to the timestamp by default, that is, the time series is used as the column, and the timestamp of each row of data is the same. For other result set alignments, see <a class="route-link" href="/UserGuide/V0.13.x/Query-Data/Result-Format.html">Query Result Alignment</a>.</li></ul><h2 id="basic-examples" tabindex="-1"><a class="header-anchor" href="#basic-examples"><span>Basic Examples</span></a></h2><h3 id="select-a-column-of-data-based-on-a-time-interval" tabindex="-1"><a class="header-anchor" href="#select-a-column-of-data-based-on-a-time-interval"><span>Select a Column of Data Based on a Time Interval</span></a></h3><p>The SQL statement is:</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> temperature <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 keyword">where</span> <span class="token keyword">time</span> <span class="token operator">&lt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">08</span>:<span class="token number">00.000</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>which means:</p><p>The selected device is ln group wf01 plant wt01 device; the selected timeseries is the temperature sensor (temperature). The SQL statement requires that all temperature sensor values before the time point of &quot;2017-11-01T00:08:00.000&quot; be selected.</p><p>The execution result of this SQL statement is as follows:</p><div class="language-text line-numbers-mode" data-ext="text" data-title="text"><pre class="language-text"><code>+-----------------------------+-----------------------------+
|                         Time|root.ln.wf01.wt01.temperature|
+-----------------------------+-----------------------------+
|2017-11-01T00:00:00.000+08:00|                        25.96|
|2017-11-01T00:01:00.000+08:00|                        24.36|
|2017-11-01T00:02:00.000+08:00|                        20.09|
|2017-11-01T00:03:00.000+08:00|                        20.18|
|2017-11-01T00:04:00.000+08:00|                        21.13|
|2017-11-01T00:05:00.000+08:00|                        22.72|
|2017-11-01T00:06:00.000+08:00|                        20.71|
|2017-11-01T00:07:00.000+08:00|                        21.45|
+-----------------------------+-----------------------------+
Total line number = 8
It costs 0.026s
</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><h3 id="select-multiple-columns-of-data-based-on-a-time-interval" tabindex="-1"><a class="header-anchor" href="#select-multiple-columns-of-data-based-on-a-time-interval"><span>Select Multiple Columns of Data Based on a Time Interval</span></a></h3><p>The SQL statement is:</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> <span class="token keyword">status</span><span class="token punctuation">,</span> temperature <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 keyword">where</span> <span class="token keyword">time</span> <span class="token operator">&gt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">05</span>:<span class="token number">00.000</span> <span class="token operator">and</span> <span class="token keyword">time</span> <span class="token operator">&lt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">12</span>:<span class="token number">00.000</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>which means:</p><p>The selected device is ln group wf01 plant wt01 device; the selected timeseries is &quot;status&quot; and &quot;temperature&quot;. The SQL statement requires that the status and temperature sensor values between the time point of &quot;2017-11-01T00:05:00.000&quot; and &quot;2017-11-01T00:12:00.000&quot; be selected.</p><p>The execution result of this SQL statement is as follows:</p><div class="language-text line-numbers-mode" data-ext="text" data-title="text"><pre class="language-text"><code>+-----------------------------+------------------------+-----------------------------+
|                         Time|root.ln.wf01.wt01.status|root.ln.wf01.wt01.temperature|
+-----------------------------+------------------------+-----------------------------+
|2017-11-01T00:06:00.000+08:00|                   false|                        20.71|
|2017-11-01T00:07:00.000+08:00|                   false|                        21.45|
|2017-11-01T00:08:00.000+08:00|                   false|                        22.58|
|2017-11-01T00:09:00.000+08:00|                   false|                        20.98|
|2017-11-01T00:10:00.000+08:00|                    true|                        25.52|
|2017-11-01T00:11:00.000+08:00|                   false|                        22.91|
+-----------------------------+------------------------+-----------------------------+
Total line number = 6
It costs 0.018s
</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><h3 id="select-multiple-columns-of-data-for-the-same-device-according-to-multiple-time-intervals" tabindex="-1"><a class="header-anchor" href="#select-multiple-columns-of-data-for-the-same-device-according-to-multiple-time-intervals"><span>Select Multiple Columns of Data for the Same Device According to Multiple Time Intervals</span></a></h3><p>IoTDB supports specifying multiple time interval conditions in a query. Users can combine time interval conditions at will according to their needs. For example, the SQL statement is:</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> <span class="token keyword">status</span><span class="token punctuation">,</span>temperature <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 keyword">where</span> <span class="token punctuation">(</span><span class="token keyword">time</span> <span class="token operator">&gt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">05</span>:<span class="token number">00.000</span> <span class="token operator">and</span> <span class="token keyword">time</span> <span class="token operator">&lt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">12</span>:<span class="token number">00.000</span><span class="token punctuation">)</span> <span class="token operator">or</span> <span class="token punctuation">(</span><span class="token keyword">time</span> <span class="token operator">&gt;=</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T16:<span class="token number">35</span>:<span class="token number">00.000</span> <span class="token operator">and</span> <span class="token keyword">time</span> <span class="token operator">&lt;=</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T16:<span class="token number">37</span>:<span class="token number">00.000</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>which means:</p><p>The selected device is ln group wf01 plant wt01 device; the selected timeseries is &quot;status&quot; and &quot;temperature&quot;; the statement specifies two different time intervals, namely &quot;2017-11-01T00:05:00.000 to 2017-11-01T00:12:00.000&quot; and &quot;2017-11-01T16:35:00.000 to 2017-11-01T16:37:00.000&quot;. The SQL statement requires that the values of selected timeseries satisfying any time interval be selected.</p><p>The execution result of this SQL statement is as follows:</p><div class="language-text line-numbers-mode" data-ext="text" data-title="text"><pre class="language-text"><code>+-----------------------------+------------------------+-----------------------------+
|                         Time|root.ln.wf01.wt01.status|root.ln.wf01.wt01.temperature|
+-----------------------------+------------------------+-----------------------------+
|2017-11-01T00:06:00.000+08:00|                   false|                        20.71|
|2017-11-01T00:07:00.000+08:00|                   false|                        21.45|
|2017-11-01T00:08:00.000+08:00|                   false|                        22.58|
|2017-11-01T00:09:00.000+08:00|                   false|                        20.98|
|2017-11-01T00:10:00.000+08:00|                    true|                        25.52|
|2017-11-01T00:11:00.000+08:00|                   false|                        22.91|
|2017-11-01T16:35:00.000+08:00|                    true|                        23.44|
|2017-11-01T16:36:00.000+08:00|                   false|                        21.98|
|2017-11-01T16:37:00.000+08:00|                   false|                        21.93|
+-----------------------------+------------------------+-----------------------------+
Total line number = 9
It costs 0.018s
</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></div><h3 id="choose-multiple-columns-of-data-for-different-devices-according-to-multiple-time-intervals" tabindex="-1"><a class="header-anchor" href="#choose-multiple-columns-of-data-for-different-devices-according-to-multiple-time-intervals"><span>Choose Multiple Columns of Data for Different Devices According to Multiple Time Intervals</span></a></h3><p>The system supports the selection of data in any column in a query, i.e., the selected columns can come from different devices. For example, the SQL statement is:</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> wf01<span class="token punctuation">.</span>wt01<span class="token punctuation">.</span><span class="token keyword">status</span><span class="token punctuation">,</span>wf02<span class="token punctuation">.</span>wt02<span class="token punctuation">.</span>hardware <span class="token keyword">from</span> root<span class="token punctuation">.</span>ln <span class="token keyword">where</span> <span class="token punctuation">(</span><span class="token keyword">time</span> <span class="token operator">&gt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">05</span>:<span class="token number">00.000</span> <span class="token operator">and</span> <span class="token keyword">time</span> <span class="token operator">&lt;</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T00:<span class="token number">12</span>:<span class="token number">00.000</span><span class="token punctuation">)</span> <span class="token operator">or</span> <span class="token punctuation">(</span><span class="token keyword">time</span> <span class="token operator">&gt;=</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T16:<span class="token number">35</span>:<span class="token number">00.000</span> <span class="token operator">and</span> <span class="token keyword">time</span> <span class="token operator">&lt;=</span> <span class="token number">2017</span><span class="token operator">-</span><span class="token number">11</span><span class="token operator">-</span><span class="token number">01</span>T16:<span class="token number">37</span>:<span class="token number">00.000</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>which means:</p><p>The selected timeseries are &quot;the power supply status of ln group wf01 plant wt01 device&quot; and &quot;the hardware version of ln group wf02 plant wt02 device&quot;; the statement specifies two different time intervals, namely &quot;2017-11-01T00:05:00.000 to 2017-11-01T00:12:00.000&quot; and &quot;2017-11-01T16:35:00.000 to 2017-11-01T16:37:00.000&quot;. The SQL statement requires that the values of selected timeseries satisfying any time interval be selected.</p><p>The execution result of this SQL statement is as follows:</p><div class="language-text line-numbers-mode" data-ext="text" data-title="text"><pre class="language-text"><code>+-----------------------------+------------------------+--------------------------+
|                         Time|root.ln.wf01.wt01.status|root.ln.wf02.wt02.hardware|
+-----------------------------+------------------------+--------------------------+
|2017-11-01T00:06:00.000+08:00|                   false|                        v1|
|2017-11-01T00:07:00.000+08:00|                   false|                        v1|
|2017-11-01T00:08:00.000+08:00|                   false|                        v1|
|2017-11-01T00:09:00.000+08:00|                   false|                        v1|
|2017-11-01T00:10:00.000+08:00|                    true|                        v2|
|2017-11-01T00:11:00.000+08:00|                   false|                        v1|
|2017-11-01T16:35:00.000+08:00|                    true|                        v2|
|2017-11-01T16:36:00.000+08:00|                   false|                        v1|
|2017-11-01T16:37:00.000+08:00|                   false|                        v1|
+-----------------------------+------------------------+--------------------------+
Total line number = 9
It costs 0.014s
</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></div><h3 id="order-by-time-query" tabindex="-1"><a class="header-anchor" href="#order-by-time-query"><span>Order By Time Query</span></a></h3><p>IoTDB supports the &#39;order by time&#39; statement since 0.11, it&#39;s used to display results in descending order by time.<br> For example, the SQL statement is:</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> <span class="token operator">*</span> <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 operator">*</span> <span class="token keyword">where</span> <span class="token keyword">time</span> <span class="token operator">&gt;</span> <span class="token number">1</span> <span class="token keyword">order</span> <span class="token keyword">by</span> <span class="token keyword">time</span> <span class="token keyword">desc</span> <span class="token keyword">limit</span> <span class="token number">10</span><span class="token punctuation">;</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>The execution result of this SQL statement is as follows:</p><div class="language-text line-numbers-mode" data-ext="text" data-title="text"><pre class="language-text"><code>+-----------------------------+--------------------------+------------------------+-----------------------------+------------------------+
|                         Time|root.ln.wf02.wt02.hardware|root.ln.wf02.wt02.status|root.ln.wf01.wt01.temperature|root.ln.wf01.wt01.status|
+-----------------------------+--------------------------+------------------------+-----------------------------+------------------------+
|2017-11-07T23:59:00.000+08:00|                        v1|                   false|                        21.07|                   false|
|2017-11-07T23:58:00.000+08:00|                        v1|                   false|                        22.93|                   false|
|2017-11-07T23:57:00.000+08:00|                        v2|                    true|                        24.39|                    true|
|2017-11-07T23:56:00.000+08:00|                        v2|                    true|                        24.44|                    true|
|2017-11-07T23:55:00.000+08:00|                        v2|                    true|                         25.9|                    true|
|2017-11-07T23:54:00.000+08:00|                        v1|                   false|                        22.52|                   false|
|2017-11-07T23:53:00.000+08:00|                        v2|                    true|                        24.58|                    true|
|2017-11-07T23:52:00.000+08:00|                        v1|                   false|                        20.18|                   false|
|2017-11-07T23:51:00.000+08:00|                        v1|                   false|                        22.24|                   false|
|2017-11-07T23:50:00.000+08:00|                        v2|                    true|                         23.7|                    true|
+-----------------------------+--------------------------+------------------------+-----------------------------+------------------------+
Total line number = 10
It costs 0.016s
</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></div><h2 id="usage-in-different-clients" tabindex="-1"><a class="header-anchor" href="#usage-in-different-clients"><span>Usage in Different Clients</span></a></h2><p>Data query statements can be used in SQL command-line terminals, JDBC, JAVA / C++ / Python / Go and other native APIs, and RESTful APIs.</p><ul><li><p>Execute the query statement in the SQL command line terminal: start the SQL command line terminal, and directly enter the query statement to execute, see <a class="route-link" href="/UserGuide/V0.13.x/QuickStart/Command-Line-Interface.html">SQL command line terminal</a>.</p></li><li><p>Execute query statements in JDBC, see <a class="route-link" href="/UserGuide/V0.13.x/API/Programming-JDBC.html">JDBC</a> for details.</p></li><li><p>Execute query statements in native APIs such as JAVA / C++ / Python / Go. For details, please refer to the relevant documentation in the Application Programming Interface chapter. The interface prototype is as follows:</p><div class="language-java line-numbers-mode" data-ext="java" data-title="java"><pre class="language-java"><code><span class="token class-name">SessionDataSet</span> <span class="token function">executeQueryStatement</span><span class="token punctuation">(</span><span class="token class-name">String</span> sql<span class="token punctuation">)</span>
</code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div></li><li><p>Used in RESTful API, see <a class="route-link" href="/UserGuide/V0.13.x/API/RestService.html">HTTP API</a> for details.</p></li></ul></div><!--[--><!----><!--]--><footer class="vp-page-meta"><div class="vp-meta-item edit-link"><a href="https://github.com/apache/iotdb-docs/edit/main/src/UserGuide/V0.13.x/Query-Data/Overview.md" rel="noopener noreferrer" target="_blank" aria-label="Found Error? Edit this page on GitHub" 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><!--]-->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="vp-meta-item git-info"><div class="update-time"><span class="vp-meta-label">Last update: </span><!----></div><!----></div></footer><nav class="vp-page-nav"><!----><a class="route-link nav-link next" href="/UserGuide/V0.13.x/Query-Data/Select-Expression.html" aria-label="Select Expression"><div class="hint">Next<span class="arrow end"></span></div><div class="link">Select Expression<!----></div></a></nav><!----><!--[--><!----><!--]--><!--]--></main><!--]--><footer style="padding-bottom:2rem;"><span id="doc-version" style="display:none;">rel/0.13</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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