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<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>You could also try with
not exists<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>select * from table2<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>where not exists (select
unique_key from table1 where table1.unique_key = table2.unique_key)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>Hugues.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 color=black face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma;color:windowtext;font-weight:bold'>De :</span></font></b><font
size=2 color=black face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma;
color:windowtext'> postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <b><span
style='font-weight:bold'>De la part de</span></b> Lee Hachadoorian<br>
<b><span style='font-weight:bold'>Envoyé :</span></b> jeudi <st1:date
Year="2012" Day="7" Month="6" ls="trans" w:st="on">7 juin 2012</st1:date> 16:31<br>
<b><span style='font-weight:bold'>À :</span></b>
postgis-users@postgis.refractions.net<br>
<b><span style='font-weight:bold'>Objet :</span></b> Re: [postgis-users]
Diff. Between 2 tables</span></font><font color=black><span style='color:windowtext'><o:p></o:p></span></font></p>
</div>
<p class=MsoNormal><font size=3 color=black face="Times New Roman"><span
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 color=black face="Times New Roman"><span
style='font-size:12.0pt'>On <st1:date Year="2012" Day="06" Month="07" ls="trans"
w:st="on">06/07/2012</st1:date> 09:14 AM, Hemin Tofiq wrote: <o:p></o:p></span></font></p>
<pre wrap=""><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt'>Thank you,<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>I have 2 tables with the same structure, so we don't need to create alias<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>for the same table, however that is fine with updated rows, how can I get<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>newly created rows?<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'><o:p> </o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>Regards,<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>Hemin<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'><o:p> </o:p></span></font></pre>
<p class=MsoNormal><font size=3 color=black face="Times New Roman"><span
style='font-size:12.0pt'>I assume you mean you have added a new row to one
table but not the "twin" table. <br>
<br>
Comparing on a unique key would look like:<br>
<br>
SELECT * <br>
FROM table1<br>
LEFT JOIN table2 ON (table1.unique_key = table2.unique_key)<br>
WHERE table2.unique_key IS NULL;<br>
<br>
I think you said you want to be able to do this on geometries. I haven't tried
this, but I assume something like this might work:<br>
<br>
SELECT * <br>
FROM table1<br>
LEFT JOIN table2 ON (ST_Equals(table1.the_geom,
table2.the_geom))<br>
WHERE table2.the_geom IS NULL;<br>
<br>
Just make sure to read the docs on ST_Equals vs. ST_OrderingEquals so that you
know which comparison you want.<br>
<br>
<a href="http://postgis.refractions.net/documentation/manual-1.5/ST_Equals.html">http://postgis.refractions.net/documentation/manual-1.5/ST_Equals.html</a><br>
<a
href="http://postgis.refractions.net/documentation/manual-1.5/ST_OrderingEquals.html">http://postgis.refractions.net/documentation/manual-1.5/ST_OrderingEquals.html</a><br>
<br>
Best,<br>
--Lee<br>
<br>
<br>
<o:p></o:p></span></font></p>
<pre><font size=2 color=black face="Courier New"><span style='font-size:10.0pt'>-- <o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>Lee Hachadoorian<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>PhD, Earth & Environmental Sciences (Geography)<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'>Research Associate, CUNY Center for Urban Research<o:p></o:p></span></font></pre><pre><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt'><a
href="http://freecity.commons.gc.cuny.edu">http://freecity.commons.gc.cuny.edu</a><o:p></o:p></span></font></pre></div>
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