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doc-exports/docs/dws/tool/dws_16_0193.html
luhuayi a5e3903f6b DWS TG 910.211 version 
Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: luhuayi <luhuayi@huawei.com>
Co-committed-by: luhuayi <luhuayi@huawei.com>
2025-04-23 13:53:01 +00:00

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<a name="EN-US_TOPIC_0000001813438744"></a><a name="EN-US_TOPIC_0000001813438744"></a>
<h1 class="topictitle1">UPDATE</h1>
<div id="body32001227"><p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_p8060118">In MySQL, <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b76729524531750">UPDATE</strong> allows the following keywords: <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b79301359431750">LOW_PRIORITY</strong>, <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b32185224431750">ORDER BY</strong>, <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b123521138831750">LIMIT</strong>, and <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b99287701331750">IGNORE</strong>.</p>
<div class="section" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_section66763463919"><h4 class="sectiontitle">LOW_PRIORITY</h4><p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_p1186115542211">With the <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b2216756410214">LOW_PRIORITY</strong> modifier, execution of <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b88418946310214">UPDATE</strong> is delayed.</p>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_p8060118"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_b1584504810186">Input</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_screen18330185120183"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span></pre></div></td><td class="code"><div><pre><span></span><span class="o">#</span><span class="w"> </span><span class="n">LOW_PRIORITY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">LOW_PRIORITY</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="mi">2</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_p53315611815"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_b1360664171916">Output</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164767_screen42227714193"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span></pre></div></td><td class="code"><div><pre><span></span><span class="c1">-- LOW_PRIORITY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">2</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_section2770201933915"><h4 class="sectiontitle">ORDER BY</h4><p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_p19579230122414">In MySQL, if an <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b16369424522">UPDATE</strong> statement includes an <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b1736912125215">ORDER BY</strong> clause, the rows will be updated in the order specified by the clause.</p>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_p8060118"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_b897790202013">Input</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_screen1251619362013"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span></pre></div></td><td class="code"><div><pre><span></span><span class="o">#</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="n">id</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_p8785143932018"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_b18996550152018">Output</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164431_screen528325392010"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span></pre></div></td><td class="code"><div><pre><span></span><span class="c1">-- ORDER BY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_section109124408391"><h4 class="sectiontitle">LIMIT</h4><p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_p1517232891914"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b52371442115212">UPDATE LIMIT</strong> syntax can be used to limit the scope. A clause is a limit on row matching. As long as the rows that satisfy the clause are found, the statements will stop, regardless of whether they have actually changed.</p>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_p8060118"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_b462343552212">Input</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_screen138616389229"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span>
<span class="normal">11</span>
<span class="normal">12</span>
<span class="normal">13</span>
<span class="normal">14</span>
<span class="normal">15</span></pre></div></td><td class="code"><div><pre><span></span><span class="o">#</span><span class="w"> </span><span class="k">LIMIT</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="p">;</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="p">,</span><span class="w"> </span><span class="mi">10</span><span class="w"> </span><span class="p">;</span>
<span class="o">#</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">OFFSET</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="k">OFFSET</span><span class="w"> </span><span class="mi">2</span><span class="p">;</span>
<span class="o">#</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="n">fname</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="p">;</span>
<span class="o">#</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">id</span><span class="o">&lt;</span><span class="mi">5</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="n">fname</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="p">;</span>
<span class="o">#</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">OFFSET</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">id</span><span class="o">&lt;</span><span class="mi">5</span><span class="w"> </span><span class="k">ORDER</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="n">fname</span><span class="w"> </span><span class="k">LIMIT</span><span class="w"> </span><span class="mi">3</span><span class="w"> </span><span class="k">OFFSET</span><span class="w"> </span><span class="mi">2</span><span class="w"> </span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_p19586832152712"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_b15245144242914">Output</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164556_screen196344592911"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal"> 1</span>
<span class="normal"> 2</span>
<span class="normal"> 3</span>
<span class="normal"> 4</span>
<span class="normal"> 5</span>
<span class="normal"> 6</span>
<span class="normal"> 7</span>
<span class="normal"> 8</span>
<span class="normal"> 9</span>
<span class="normal">10</span>
<span class="normal">11</span>
<span class="normal">12</span>
<span class="normal">13</span>
<span class="normal">14</span>
<span class="normal">15</span></pre></div></td><td class="code"><div><pre><span></span><span class="c1">-- LIMIT</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="p">;</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="p">;</span>
<span class="c1">-- LIMIT + OFFSET</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="p">;</span>
<span class="c1">-- LIMIT + ORDER BY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="p">;</span>
<span class="c1">-- LIMIT + WHERE + ORDER BY</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">id</span><span class="o">&lt;</span><span class="mi">5</span><span class="p">;</span>
<span class="c1">-- LIMIT + WHERE + ORDER BY + OFFSET</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">department_id</span><span class="o">+</span><span class="mi">1</span><span class="w"> </span><span class="k">WHERE</span><span class="w"> </span><span class="n">id</span><span class="o">&lt;</span><span class="mi">5</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
</div>
<div class="section" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_section48891264401"><h4 class="sectiontitle">IGNORE</h4><p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_p54501782310">With the <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b84698549310214">IGNORE</strong> modifier, the <strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_b127109518510214">UPDATE</strong> statement does not abort even if errors occur during execution.</p>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_p8060118"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_b658074915481">Input</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_screen155688533483"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span></pre></div></td><td class="code"><div><pre><span></span><span class="o">#</span><span class="w"> </span><span class="k">IGNORE</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="k">IGNORE</span><span class="w"> </span><span class="n">employees</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="n">department_id</span><span class="o">=</span><span class="mi">3</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_p12420113164917"><strong id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_b8832111034915">Output</strong></p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001813438744__en-us_topic_0000001432327713_en-us_topic_0214164649_screen1445841344913"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span>
<span class="normal">2</span></pre></div></td><td class="code"><div><pre><span></span><span class="c1">-- IGNORE</span>
<span class="k">UPDATE</span><span class="w"> </span><span class="ss">&quot;public&quot;</span><span class="p">.</span><span class="ss">&quot;employees&quot;</span><span class="w"> </span><span class="k">SET</span><span class="w"> </span><span class="ss">&quot;department_id&quot;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">3</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dws_16_0177.html">Data Manipulation Language (DML)</a></div>
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