<div class="gmail_extra">Hi,</div><div class="gmail_extra"><br></div><div class="gmail_extra">As Julien suggested, you could st_dump to explode multipolygons into polygons, then union them.</div><div class="gmail_extra">It will produce a single polygon unioning all others:</div>
<div class="gmail_extra"><br></div><div class="gmail_extra">with t as (</div><div class="gmail_extra"> select (st_dump(geom)).geom </div><div class="gmail_extra"> from my_table</div><div class="gmail_extra">) select st_union(geom) from t;</div>
<div class="gmail_extra"><br></div><div class="gmail_extra">Nicolas<br><br><div class="gmail_quote">On 26 April 2012 17:22, Mehmet Erkek <span dir="ltr"><<a href="mailto:merkek@reidin.com" target="_blank">merkek@reidin.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div bgcolor="white" lang="EN-US" link="blue" vlink="purple"><div><p class="MsoNormal"><span style="color:windowtext">Hi Juilen, thanks for quick answer. <u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:windowtext"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:windowtext">I have </span><span style="color:windowtext">1 geometry and 1 row on the table. this geometry is multiploygon which consists of 4 polygons.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="color:windowtext">I want to convert this mutlipolygon to one single polygon..<u></u><u></u></span></p><p class="MsoNormal"><span style="color:windowtext"><u></u> <u></u></span></p><p class="MsoNormal">
<span style="color:windowtext">Any idea how I can do this?<u></u><u></u></span></p><p class="MsoNormal"><span style="color:windowtext">I hope it is clearer now.<u></u><u></u></span></p><p class="MsoNormal"><span style="color:windowtext"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="color:windowtext">Thanks.<u></u><u></u></span></p><p class="MsoNormal"><span style="color:#1f497d"><u></u> <u></u></span></p><p class="MsoNormal"><span style="color:#1f497d"><u></u> <u></u></span></p>
<div><div style="border:none;border-top:solid #b5c4df 1.0pt;padding:3.0pt 0cm 0cm 0cm"><p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext"> <a href="mailto:postgis-users-bounces@postgis.refractions.net" target="_blank">postgis-users-bounces@postgis.refractions.net</a> [mailto:<a href="mailto:postgis-users-bounces@postgis.refractions.net" target="_blank">postgis-users-bounces@postgis.refractions.net</a>] <b>On Behalf Of </b>ju<br>
<b>Sent:</b> 26 Nisan 2012 18:02<br><b>To:</b> PostGIS Users Discussion<br><b>Subject:</b> Re: [postgis-users] [!! SPAM] multipolygon to single polygon<u></u><u></u></span></p></div></div><div><div class="h5"><p class="MsoNormal">
<u></u> <u></u></p><p class="MsoNormal">not clear...<br><br>1) if you have 4 polygons in 4 rows table distinct, this is not a multi object issu. for this case use<br> dissolve to group polygone into only one, this is not a topic of dump.<br>
<br><br>2) if you have 1 geometry and 1 row on the tablme, so this is a multi object topic<br>you must sperate the differents objet of the collection<br><br>here : <a href="http://www.postgis.org/docs/ST_GeometryN.html" target="_blank">http://www.postgis.org/docs/ST_GeometryN.html</a><u></u><u></u></p>
<pre>--Extracting all geometries (useful when you want to assign an id)<u></u><u></u></pre><pre>SELECT gid, n, ST_GeometryN(the_geom, n)<u></u><u></u></pre><pre>FROM sometable CROSS JOIN generate_series(1,100) n<u></u><u></u></pre>
<pre>WHERE n <= ST_NumGeometries(the_geom);<u></u><u></u></pre><p class="MsoNormal"><br>best regards, julien<br><br><br><br>Le 26/04/2012 16:27, Mehmet Erkek a écrit : <u></u><u></u></p><p class="MsoNormal"> <u></u><u></u></p>
<p class="MsoNormal">I have multipolygons which I would like to convert a single polygon. is there a way to do this? please check the attached image. I tried st_dump and afterwards st_union , but eventually I get a multipolygon again, not polygon. <u></u><u></u></p>
<p class="MsoNormal"> <u></u><u></u></p><p class="MsoNormal"> <u></u><u></u></p><p class="MsoNormal"><img border="0" width="851" height="341" src="cid:image001.png@01CD23D8.DD4DE470"><u></u><u></u></p><p class="MsoNormal">
<u></u><u></u></p><p class="MsoNormal"><b><span style="font-size:10.0pt">Mehmet Erkek</span></b><u></u><u></u></p><p class="MsoNormal"><a href="http://www.reidin.com/" target="_blank"><span style="font-size:7.0pt;font-family:"Verdana","sans-serif"">www.REIDIN.com</span></a><span style="font-size:7.0pt;font-family:"Verdana","sans-serif""> </span><u></u><u></u></p>
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