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Lu, Huayi e6fa411af0 DWS DEV 830.201 version 
Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: Lu, Huayi <luhuayi@huawei.com>
Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
2024-05-16 07:24:04 +00:00

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<a name="EN-US_TOPIC_0000001233430187"></a><a name="EN-US_TOPIC_0000001233430187"></a>
<h1 class="topictitle1">ALTER SEQUENCE</h1>
<div id="body1496994342650"><div class="section" id="EN-US_TOPIC_0000001233430187__sdac49e22fb244ca9857f4677afae4cf5"><h4 class="sectiontitle">Function</h4><p id="EN-US_TOPIC_0000001233430187__a25c220163ed048bb8c3fa4d979c0e212">Modifies the sequence definition.</p>
</div>
<div class="section" id="EN-US_TOPIC_0000001233430187__s140d83dd56de4bf495a51fb67c81f4d2"><h4 class="sectiontitle">Precautions</h4><ul id="EN-US_TOPIC_0000001233430187__ul18451101592317"><li id="EN-US_TOPIC_0000001233430187__li114511915102313">You must be the owner of the sequence to use <strong id="EN-US_TOPIC_0000001233430187__b842352706151332">ALTER SEQUENCE</strong>.</li><li id="EN-US_TOPIC_0000001233430187__li445118158235">In the current version, you can modify only the owner, home column, and the maximum value. To modify other parameters, delete the sequence and create it again. Then, use the Setval function to restore original parameter values.</li><li id="EN-US_TOPIC_0000001233430187__li83519110514"><strong id="EN-US_TOPIC_0000001233430187__b123916298815">ALTER SEQUENCE MAXVALUE</strong> cannot be used in transactions, functions, and stored procedures.</li><li id="EN-US_TOPIC_0000001233430187__li1091555112578">After the maximum value of a sequence is changed, the cache of the sequence in all sessions is cleared.</li><li id="EN-US_TOPIC_0000001233430187__li97721045848"><strong id="EN-US_TOPIC_0000001233430187__b168617165910">ALTER SEQUENCE</strong> blocks the invocation of <strong id="EN-US_TOPIC_0000001233430187__b192511120299">nextval</strong>, <strong id="EN-US_TOPIC_0000001233430187__b263916221696">setval</strong>, <strong id="EN-US_TOPIC_0000001233430187__b1490882511916">currval</strong>, and <strong id="EN-US_TOPIC_0000001233430187__b13357285910">lastval</strong>.</li></ul>
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<div class="section" id="EN-US_TOPIC_0000001233430187__sf9c7d15c4e5d447b817eab0668e2de87"><h4 class="sectiontitle">Syntax</h4><p id="EN-US_TOPIC_0000001233430187__a1e4ffe6211694948ac2a3dbf8475869c">Change the maximum value or home column of the sequence.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001233430187__s318ed4f310cc4b8190d70f27c9710eb6"><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></pre></div></td><td class="code"><div><pre><span></span><span class="k">ALTER</span><span class="w"> </span><span class="n">SEQUENCE</span><span class="w"> </span><span class="p">[</span><span class="w"> </span><span class="k">IF</span><span class="w"> </span><span class="k">EXISTS</span><span class="w"> </span><span class="p">]</span><span class="w"> </span><span class="n">name</span><span class="w"> </span>
<span class="w"> </span><span class="p">[</span><span class="w"> </span><span class="k">MAXVALUE</span><span class="w"> </span><span class="k">maxvalue</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">NO</span><span class="w"> </span><span class="k">MAXVALUE</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="n">NOMAXVALUE</span><span class="w"> </span><span class="p">]</span>
<span class="w"> </span><span class="p">[</span><span class="w"> </span><span class="n">OWNED</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="err">{</span><span class="w"> </span><span class="k">table_name</span><span class="p">.</span><span class="k">column_name</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="k">NONE</span><span class="w"> </span><span class="err">}</span><span class="w"> </span><span class="p">]</span><span class="w"> </span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001233430187__a7d2f2d4ec20944779bd4d362f71ca7c1">Change the owner of a sequence.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001233430187__sfb3555ea4ccb4d3d9f2594e245b2898b"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">ALTER</span><span class="w"> </span><span class="n">SEQUENCE</span><span class="w"> </span><span class="p">[</span><span class="w"> </span><span class="k">IF</span><span class="w"> </span><span class="k">EXISTS</span><span class="w"> </span><span class="p">]</span><span class="w"> </span><span class="n">name</span><span class="w"> </span><span class="k">OWNER</span><span class="w"> </span><span class="k">TO</span><span class="w"> </span><span class="n">new_owner</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
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<div class="section" id="EN-US_TOPIC_0000001233430187__sb64d6344b6a74ff599ad32312abe74b1"><h4 class="sectiontitle">Parameter Description</h4><ul id="EN-US_TOPIC_0000001233430187__ub0e44bad2b05425b90aac42cbec18a85"><li id="EN-US_TOPIC_0000001233430187__laed3994ca06a4304b68acc31a197ee4f"><strong id="EN-US_TOPIC_0000001233430187__b1349323111150">name</strong><p id="EN-US_TOPIC_0000001233430187__a193655b5cc5f4182bfa2cc7889ecbb9b">Specifies the sequence name to be changed.</p>
</li><li id="EN-US_TOPIC_0000001233430187__la0d848693f0940d5a8b3e3dde84ed8f2"><strong id="EN-US_TOPIC_0000001233430187__b13381534111517">IF EXISTS</strong><p id="EN-US_TOPIC_0000001233430187__a5d2476384a0e41feaf809b485bf62022">Sends a notification instead of an error when you are modifying a non-existing sequence.</p>
</li><li id="EN-US_TOPIC_0000001233430187__li88481312183516"><strong id="EN-US_TOPIC_0000001233430187__b186411037171519">MAXVALUE maxvalue | NO MAXVALUE</strong><p id="EN-US_TOPIC_0000001233430187__p052702411561">Maximum value of a sequence. If <strong id="EN-US_TOPIC_0000001233430187__b842352706135640">NO MAXVALUE</strong> is declared, the default value of the ascending sequence is <strong id="EN-US_TOPIC_0000001233430187__b842352706135720">2<sup id="EN-US_TOPIC_0000001233430187__sup534742802135837">63</sup>-1</strong>, and that of the descending sequence is <strong id="EN-US_TOPIC_0000001233430187__b842352706135753">-1</strong>. <strong id="EN-US_TOPIC_0000001233430187__b842352706194235">NOMAXVALUE</strong> is equivalent to <strong id="EN-US_TOPIC_0000001233430187__b842352706194237">NO MAXVALUE</strong>.</p>
</li><li id="EN-US_TOPIC_0000001233430187__l6f19c5a864984811ae67e4875c6e8a7a"><strong id="EN-US_TOPIC_0000001233430187__b1432544191514">OWNED BY</strong><p id="EN-US_TOPIC_0000001233430187__a8ec459e430664042beea186c6f6ad914">Associates a sequence with a specified column included in a table. In this way, the sequence will be deleted when you delete its associated field or the table where the field belongs.</p>
<p id="EN-US_TOPIC_0000001233430187__aa4f0d33f65eb4426b7dfae98abff89dc">If the sequence has been associated with another table before you use this parameter, the new association will overwrite the old one.</p>
<p id="EN-US_TOPIC_0000001233430187__adbc409e1d1804acfa1150ae04576b9ee">The associated table and sequence must be owned by the same user and in the same schema.</p>
<p id="EN-US_TOPIC_0000001233430187__a6581df88ae5046d2b018232af7a03e95">If <strong id="EN-US_TOPIC_0000001233430187__b842352706173548">OWNED BY NONE</strong> is used, existing associations will be deleted.</p>
</li><li id="EN-US_TOPIC_0000001233430187__l220339ab6e4f4803a46e6943a4598131"><strong id="EN-US_TOPIC_0000001233430187__b152851945131515">new_owner</strong><p id="EN-US_TOPIC_0000001233430187__a1a74e6dfd9564ec69efde83bfc29e03d">Specifies the user name of the new owner. To change the owner, you must also be a direct or indirect member of the new role, and this role must have <strong id="EN-US_TOPIC_0000001233430187__b1956220071218">CREATE</strong> permission on the sequence's schema.</p>
</li></ul>
</div>
<div class="section" id="EN-US_TOPIC_0000001233430187__s55a2463e8b974d2abd4be1e246d7bbd2"><h4 class="sectiontitle">Examples</h4><p id="EN-US_TOPIC_0000001233430187__a24b7672894d84879b47ee7c283987333">Create the example sequence <strong id="EN-US_TOPIC_0000001233430187__b02081594397">seq_test</strong> and example table <strong id="EN-US_TOPIC_0000001233430187__b155911815404">t1</strong>:</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001233430187__sb550f83e8ead4ae5ab42f6ef0a5e7361"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">CREATE</span><span class="w"> </span><span class="n">SEQUENCE</span><span class="w"> </span><span class="n">seq_test</span><span class="w"> </span><span class="k">START</span><span class="w"> </span><span class="mi">101</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001233430187__screen910816369410"><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="k">DROP</span><span class="w"> </span><span class="k">TABLE</span><span class="w"> </span><span class="k">IF</span><span class="w"> </span><span class="k">EXISTS</span><span class="w"> </span><span class="n">t1</span><span class="p">;</span>
<span class="k">CREATE</span><span class="w"> </span><span class="k">TABLE</span><span class="w"> </span><span class="n">t1</span><span class="p">(</span><span class="n">c1</span><span class="w"> </span><span class="nb">bigint</span><span class="w"> </span><span class="k">default</span><span class="w"> </span><span class="n">nextval</span><span class="p">(</span><span class="s1">'seq_test'</span><span class="p">));</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001233430187__p113831178107">Modify the maximum value of <strong id="EN-US_TOPIC_0000001233430187__b197310874533245">serial</strong> to <strong id="EN-US_TOPIC_0000001233430187__b124269335233245">200</strong>.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001233430187__screen69312213114"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">ALTER</span><span class="w"> </span><span class="n">SEQUENCE</span><span class="w"> </span><span class="n">seq_test</span><span class="w"> </span><span class="k">MAXVALUE</span><span class="w"> </span><span class="mi">200</span><span class="p">;</span>
</pre></div></td></tr></table></div>
</div>
<p id="EN-US_TOPIC_0000001233430187__p16383171717108">Change the column of the <strong id="EN-US_TOPIC_0000001233430187__b9603112033245">seq_test</strong> sequence to <strong id="EN-US_TOPIC_0000001233430187__b154146860833245">t1.c1</strong>.</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001233430187__screen9341414191120"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">ALTER</span><span class="w"> </span><span class="n">SEQUENCE</span><span class="w"> </span><span class="n">seq_test</span><span class="w"> </span><span class="n">OWNED</span><span class="w"> </span><span class="k">BY</span><span class="w"> </span><span class="n">t1</span><span class="p">.</span><span class="n">c1</span><span class="p">;</span>
</pre></div></td></tr></table></div>
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<div class="section" id="EN-US_TOPIC_0000001233430187__s3483b183277645ada8c7bae9cf1dcaa5"><h4 class="sectiontitle">Helpful Links</h4><p id="EN-US_TOPIC_0000001233430187__a42904cb8e80348f5ae2afe0370053b5e"><a href="dws_06_0174.html">CREATE SEQUENCE</a>, <a href="dws_06_0205.html">DROP SEQUENCE</a></p>
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<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dws_06_0118.html">DDL Syntax</a></div>
</div>
</div>
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