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<p>我已将csv文件中的数据复制到表<code>stage_table</code>中的列:</p>
<pre><code>aid
a_name
addrid
addr1
addr2
city
pstate
country
postalcd
contactnumber
attendancekey
attendancedate
attendedyesno
action_indicator
</code></pre>
<p>当同一个表中的<code>aid</code>存在多次时,我试图将表中的<code>action_indicator</code>列设为“Y”(默认情况下,该列设置为“N”)。你知道吗</p>
<p>我尝试了这个查询,但不起作用</p>
<pre><code>update_address_query = ("update public.address set active_ind=case
when count(aid)>1 then 'Y' end from address")
cur.execute(update_address_query)
</code></pre>
<p>我收到的错误是:</p>
<blockquote>
<p>psycopg2.errors.DuplicateAlias: table name "address" specified more than once</p>
</blockquote>
<p>这是否可以通过其他方式加以纠正?你知道吗</p>
<p>此地址表中的列是</p>
<blockquote>
<p>addrid</p>
<p>addr1</p>
<p>addr2</p>
<p>city</p>
<p>pstate</p>
<p>country</p>
<p>postalcd</p>
<p>contactnumber</p>
<p>active_indicator</p>
</blockquote>
<p>示例输出应如下所示:</p>
<blockquote>
<p>99801,No-13 4rthcrossst,GandiNagar,Bangalore,Karnataka,India,456009,7800912345,N</p>
<p>99802,No-14 5thcrossst,NehruNagar,Hyderabad,Telangana,India,556001,6800612345,N</p>
<p>99803,No-15 6thcrossst,SardarNagar,Ahmedabad,Gujarat,India,356009,9800912345,N</p>
<p>99804,No-16 7thcrossst,PatelNagar,Bangalore,Karnataka,India,456009,5800912345,N</p>
<p>99805,No-17 8thcrossst,AnnaNagar,Chennai,TamilNadu,India,456009,4800912345,N</p>
<p>99801,No-13 4rthcrossst,GandiNagar,Bangalore,Karnataka,India,456009,7800912345,Y</p>
<p>99802,No-14 5thcrossst,NehruNagar,Hyderabad,Telangana,India,556001,6800612345,Y</p>
<p>99803,No-15 6thcrossst,SardarNagar,Ahmedabad,Gujarat,India,356009,9800912345,Y</p>
<p>99804,No-16 7thcrossst,PatelNagar,Bangalore,Karnataka,India,456009,5800912345,Y</p>
<p>99805,No-17 8thcrossst,AnnaNagar,Chennai,TamilNadu,India,456009,4800912345,Y</p>
<p>99801,No-13 4rthcrossst,GandiNagar,Bangalore,Karnataka,India,456009,7800912345,Y</p>
<p>99802,No-14 5thcrossst,NehruNagar,Hyderabad,Telangana,India,556001,6800612345,Y</p>
<p>99803,No-15 6thcrossst,SardarNagar,Ahmedabad,Gujarat,India,356009,9800912345,Y</p>
<p>99804,No-16 7thcrossst,PatelNagar,Bangalore,Karnataka,India,456009,5800912345,Y</p>
<p>99805,No-17 8thcrossst,AnnaNagar,Chennai,TamilNadu,India,456009,4800912345,Y</p>
</blockquote>