| import{_ as n,O as s,P as e,ah as a,aW as l}from"./framework-62ad666a.js";const t={},i=l(`<h2 id="查询结果分页" tabindex="-1"><a class="header-anchor" href="#查询结果分页" aria-hidden="true">#</a> 查询结果分页</h2><p>当查询结果集数据量很大，放在一个页面不利于显示，可以使用 <code>LIMIT/SLIMIT</code> 子句和 <code>OFFSET/SOFFSET </code>子句进行分页控制。</p><ul><li><code>LIMIT</code> 和 <code>SLIMIT</code> 子句用于控制查询结果的行数和列数。</li><li><code>OFFSET</code> 和 <code>SOFFSET</code> 子句用于控制结果显示的起始位置。</li></ul><h3 id="按行分页" tabindex="-1"><a class="header-anchor" href="#按行分页" aria-hidden="true">#</a> 按行分页</h3><p>用户可以通过 <code>LIMIT</code> 和 <code>OFFSET</code> 子句控制查询结果的行数，<code>LIMIT rowLimit</code> 指定查询结果的行数，<code>OFFSET rowOffset</code> 指定查询结果显示的起始行位置。</p><p>注意：</p><ul><li>当 <code>rowOffset</code> 超过结果集的大小时，返回空结果集。</li><li>当 <code>rowLimit</code> 超过结果集的大小时，返回所有查询结果。</li><li>当 <code>rowLimit</code> 和 <code>rowOffset</code> 不是正整数，或超过 <code>INT64</code> 允许的最大值时，系统将提示错误。</li></ul><p>我们将通过以下示例演示如何使用 <code>LIMIT</code> 和 <code>OFFSET</code> 子句。</p><ul><li><strong>示例 1：</strong> 基本的 <code>LIMIT</code> 子句</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="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">limit</span> <span class="token number">10</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>所选设备为 ln 组 wf01 工厂 wt01 设备； 选择的时间序列是“状态”和“温度”。 SQL 语句要求返回查询结果的前 10 行。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+------------------------+-----------------------------+ |
| | Time|root.ln.wf01.wt01.status|root.ln.wf01.wt01.temperature| |
| +-----------------------------+------------------------+-----------------------------+ |
| |2017-11-01T00:00:00.000+08:00| true| 25.96| |
| |2017-11-01T00:01:00.000+08:00| true| 24.36| |
| |2017-11-01T00:02:00.000+08:00| false| 20.09| |
| |2017-11-01T00:03:00.000+08:00| false| 20.18| |
| |2017-11-01T00:04:00.000+08:00| false| 21.13| |
| |2017-11-01T00:05:00.000+08:00| false| 22.72| |
| |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| |
| +-----------------------------+------------------------+-----------------------------+ |
| Total line number = 10 |
| It costs 0.000s |
| </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><ul><li><strong>示例 2：</strong> 带 <code>OFFSET</code> 的 <code>LIMIT</code> 子句</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="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">limit</span> <span class="token number">5</span> <span class="token keyword">offset</span> <span class="token number">3</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>所选设备为 ln 组 wf01 工厂 wt01 设备； 选择的时间序列是“状态”和“温度”。 SQL 语句要求返回查询结果的第 3 至 7 行（第一行编号为 0 行）。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+------------------------+-----------------------------+ |
| | Time|root.ln.wf01.wt01.status|root.ln.wf01.wt01.temperature| |
| +-----------------------------+------------------------+-----------------------------+ |
| |2017-11-01T00:03:00.000+08:00| false| 20.18| |
| |2017-11-01T00:04:00.000+08:00| false| 21.13| |
| |2017-11-01T00:05:00.000+08:00| false| 22.72| |
| |2017-11-01T00:06:00.000+08:00| false| 20.71| |
| |2017-11-01T00:07:00.000+08:00| false| 21.45| |
| +-----------------------------+------------------------+-----------------------------+ |
| Total line number = 5 |
| It costs 0.342s |
| </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><ul><li><strong>示例 3：</strong> <code>LIMIT</code> 子句与 <code>WHERE</code> 子句结合</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="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">></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"><</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 keyword">limit</span> <span class="token number">5</span> <span class="token keyword">offset</span> <span class="token number">3</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>所选设备为 ln 组 wf01 工厂 wt01 设备； 选择的时间序列是“状态”和“温度”。 SQL 语句要求返回时间“ 2017-11-01T00：05：00.000”和“ 2017-11-01T00：12：00.000”之间的状态和温度传感器值的第 3 至 4 行（第一行） 编号为第 0 行）。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+------------------------+-----------------------------+ |
| | Time|root.ln.wf01.wt01.status|root.ln.wf01.wt01.temperature| |
| +-----------------------------+------------------------+-----------------------------+ |
| |2017-11-01T00:03:00.000+08:00| false| 20.18| |
| |2017-11-01T00:04:00.000+08:00| false| 21.13| |
| |2017-11-01T00:05:00.000+08:00| false| 22.72| |
| |2017-11-01T00:06:00.000+08:00| false| 20.71| |
| |2017-11-01T00:07:00.000+08:00| false| 21.45| |
| +-----------------------------+------------------------+-----------------------------+ |
| Total line number = 5 |
| It costs 0.000s |
| </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><ul><li><strong>示例 4：</strong> <code>LIMIT</code> 子句与 <code>GROUP BY</code> 子句组合</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> <span class="token function">count</span><span class="token punctuation">(</span><span class="token keyword">status</span><span class="token punctuation">)</span><span class="token punctuation">,</span> max_value<span class="token punctuation">(</span>temperature<span class="token punctuation">)</span> <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">group</span> <span class="token keyword">by</span> <span class="token punctuation">(</span><span class="token punctuation">[</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">00</span>:<span class="token number">00</span><span class="token punctuation">,</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">07</span>T23:<span class="token number">00</span>:<span class="token number">00</span><span class="token punctuation">)</span><span class="token punctuation">,</span><span class="token number">1</span>d<span class="token punctuation">)</span> <span class="token keyword">limit</span> <span class="token number">4</span> <span class="token keyword">offset</span> <span class="token number">3</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>SQL 语句子句要求返回查询结果的第 3 至 6 行（第一行编号为 0 行）。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+-------------------------------+----------------------------------------+ |
| | Time|count(root.ln.wf01.wt01.status)|max_value(root.ln.wf01.wt01.temperature)| |
| +-----------------------------+-------------------------------+----------------------------------------+ |
| |2017-11-04T00:00:00.000+08:00| 1440| 26.0| |
| |2017-11-05T00:00:00.000+08:00| 1440| 26.0| |
| |2017-11-06T00:00:00.000+08:00| 1440| 25.99| |
| |2017-11-07T00:00:00.000+08:00| 1380| 26.0| |
| +-----------------------------+-------------------------------+----------------------------------------+ |
| Total line number = 4 |
| 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></div><h3 id="按列分页" tabindex="-1"><a class="header-anchor" href="#按列分页" aria-hidden="true">#</a> 按列分页</h3><p>用户可以通过 <code>SLIMIT</code> 和 <code>SOFFSET</code> 子句控制查询结果的列数，<code>SLIMIT seriesLimit</code> 指定查询结果的列数，<code>SOFFSET seriesOffset</code> 指定查询结果显示的起始列位置。</p><p>注意：</p><ul><li>仅用于控制值列，对时间列和设备列无效。</li><li>当 <code>seriesOffset</code> 超过结果集的大小时，返回空结果集。</li><li>当 <code>seriesLimit</code> 超过结果集的大小时，返回所有查询结果。</li><li>当 <code>seriesLimit</code> 和 <code>seriesOffset</code> 不是正整数，或超过 <code>INT64</code> 允许的最大值时，系统将提示错误。</li></ul><p>我们将通过以下示例演示如何使用 <code>SLIMIT</code> 和 <code>SOFFSET</code> 子句。</p><ul><li><strong>示例 1：</strong> 基本的 <code>SLIMIT</code> 子句</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="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>wf01<span class="token punctuation">.</span>wt01 <span class="token keyword">where</span> <span class="token keyword">time</span> <span class="token operator">></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"><</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> slimit <span class="token number">1</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>所选设备为 ln 组 wf01 工厂 wt01 设备； 所选时间序列是该设备下的第二列，即温度。 SQL 语句要求在"2017-11-01T00:05:00.000"和"2017-11-01T00:12:00.000"的时间点之间选择温度传感器值。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+-----------------------------+ |
| | Time|root.ln.wf01.wt01.temperature| |
| +-----------------------------+-----------------------------+ |
| |2017-11-01T00:06:00.000+08:00| 20.71| |
| |2017-11-01T00:07:00.000+08:00| 21.45| |
| |2017-11-01T00:08:00.000+08:00| 22.58| |
| |2017-11-01T00:09:00.000+08:00| 20.98| |
| |2017-11-01T00:10:00.000+08:00| 25.52| |
| |2017-11-01T00:11:00.000+08:00| 22.91| |
| +-----------------------------+-----------------------------+ |
| Total line number = 6 |
| It costs 0.000s |
| </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><ul><li><strong>示例 2：</strong> 带 <code>SOFFSET</code> 的 <code>SLIMIT</code> 子句</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="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>wf01<span class="token punctuation">.</span>wt01 <span class="token keyword">where</span> <span class="token keyword">time</span> <span class="token operator">></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"><</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> slimit <span class="token number">1</span> soffset <span class="token number">1</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>所选设备为 ln 组 wf01 工厂 wt01 设备； 所选时间序列是该设备下的第一列，即电源状态。 SQL 语句要求在" 2017-11-01T00:05:00.000"和"2017-11-01T00:12:00.000"的时间点之间选择状态传感器值。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+------------------------+ |
| | Time|root.ln.wf01.wt01.status| |
| +-----------------------------+------------------------+ |
| |2017-11-01T00:06:00.000+08:00| false| |
| |2017-11-01T00:07:00.000+08:00| false| |
| |2017-11-01T00:08:00.000+08:00| false| |
| |2017-11-01T00:09:00.000+08:00| false| |
| |2017-11-01T00:10:00.000+08:00| true| |
| |2017-11-01T00:11:00.000+08:00| false| |
| +-----------------------------+------------------------+ |
| Total line number = 6 |
| It costs 0.003s |
| </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><ul><li><strong>示例 3：</strong> <code>SLIMIT</code> 子句与 <code>GROUP BY</code> 子句结合</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="sql"><pre class="language-sql"><code><span class="token keyword">select</span> max_value<span class="token punctuation">(</span><span class="token operator">*</span><span class="token punctuation">)</span> <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">group</span> <span class="token keyword">by</span> <span class="token punctuation">(</span><span class="token punctuation">[</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">00</span>:<span class="token number">00</span><span class="token punctuation">,</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">07</span>T23:<span class="token number">00</span>:<span class="token number">00</span><span class="token punctuation">)</span><span class="token punctuation">,</span><span class="token number">1</span>d<span class="token punctuation">)</span> slimit <span class="token number">1</span> soffset <span class="token number">1</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+-----------------------------------+ |
| | Time|max_value(root.ln.wf01.wt01.status)| |
| +-----------------------------+-----------------------------------+ |
| |2017-11-01T00:00:00.000+08:00| true| |
| |2017-11-02T00:00:00.000+08:00| true| |
| |2017-11-03T00:00:00.000+08:00| true| |
| |2017-11-04T00:00:00.000+08:00| true| |
| |2017-11-05T00:00:00.000+08:00| true| |
| |2017-11-06T00:00:00.000+08:00| true| |
| |2017-11-07T00:00:00.000+08:00| true| |
| +-----------------------------+-----------------------------------+ |
| Total line number = 7 |
| It costs 0.000s |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div><div class="line-number"></div></div></div><ul><li><strong>示例 4：</strong> <code>SLIMIT</code> 子句与 <code>LIMIT</code> 子句结合</li></ul><p>SQL 语句：</p><div class="language-sql line-numbers-mode" data-ext="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>wf01<span class="token punctuation">.</span>wt01 <span class="token keyword">limit</span> <span class="token number">10</span> <span class="token keyword">offset</span> <span class="token number">100</span> slimit <span class="token number">2</span> soffset <span class="token number">0</span> |
| </code></pre><div class="line-numbers" aria-hidden="true"><div class="line-number"></div></div></div><p>含义：</p><p>所选设备为 ln 组 wf01 工厂 wt01 设备； 所选时间序列是此设备下的第 0 列至第 1 列（第一列编号为第 0 列）。 SQL 语句子句要求返回查询结果的第 100 至 109 行（第一行编号为 0 行）。</p><p>结果如下所示：</p><div class="language-text line-numbers-mode" data-ext="text"><pre class="language-text"><code>+-----------------------------+-----------------------------+------------------------+ |
| | Time|root.ln.wf01.wt01.temperature|root.ln.wf01.wt01.status| |
| +-----------------------------+-----------------------------+------------------------+ |
| |2017-11-01T01:40:00.000+08:00| 21.19| false| |
| |2017-11-01T01:41:00.000+08:00| 22.79| false| |
| |2017-11-01T01:42:00.000+08:00| 22.98| false| |
| |2017-11-01T01:43:00.000+08:00| 21.52| false| |
| |2017-11-01T01:44:00.000+08:00| 23.45| true| |
| |2017-11-01T01:45:00.000+08:00| 24.06| true| |
| |2017-11-01T01:46:00.000+08:00| 22.6| false| |
| |2017-11-01T01:47:00.000+08:00| 23.78| true| |
| |2017-11-01T01:48:00.000+08:00| 24.72| true| |
| |2017-11-01T01:49:00.000+08:00| 24.68| true| |
| +-----------------------------+-----------------------------+------------------------+ |
| Total line number = 10 |
| It costs 0.009s |
| </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>`,67);function o(p,c){return s(),e("div",null,[a(` |
| |
| Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you under the Apache License, Version 2.0 (the |
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| http://www.apache.org/licenses/LICENSE-2.0 |
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| "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| KIND, either express or implied. See the License for the |
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| |
| `),i])}const r=n(t,[["render",o],["__file","Pagination.html.vue"]]);export{r as default}; |
