Обсуждение:

<pre><pre>hello,<br />everyone!<br /> I want to know how postgresql remain its unique index unique after <br />i have
changeit.For example:<br /> create table human(age int,name char(2));<br />then in the pg_attribute catalog the unique
indexpg_attribute_relid_attnum_index will<br />use relid of 'human'and attnum of age to create a index tuple for
attribute:age,whichis a unique index tuple for a tuple which describe age in pg_attribute,and i do:<br /> alter table
humanrename age to birthdate;<br />then in the unique index pg_attribute_relid_attnum_index will appear two index tuple
<br/>which keys are relid of 'human' and attnum:1 to describe age ,but there is no error happening!!!!So i am
interestedin the method of remain the dynamic index very much.<br /> would you please tell how postgres do it and the
srcof this? <br />thanks :) </pre><pre> </pre><pre>　　　　　　　　致<br />礼！<br />     </pre><pre>　　　　　　　　庄继锋<br />　　　　　　　　<a
href="mailto:zhuangjifeng@263.net">zhuangjifeng@263.net</a><br/>　　　　　　　　　　2004-04-29</pre></pre>
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zhuangjifeng <zhuangjifeng@263.net> writes:
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I'd have answered this if my editor could quote it reasonably,
but I don't have the energy to deal with the above...

In future, please post to pghackers in plain text (lose the
HTML, too) and include a relevant Subject: line.
        regards, tom lane