Hi Pierre,<br><br>We do not know yet.. it could be even hundreds ! <br><br>each region (european country, US state, province, etc...) would have few raster (even 20) representing different kind of information... (each pixel would be 5mx5rm)... and I need to know the value of a pixel for all the rasters in that particular coordinates...<br>
<br>with Oracle 11g GEORaster it is possible to compress the rasters (and get lower performance of course)... in my case the compression rate is up to 600 !!!... so the amount of data is drastically reduced...<br>
<br>nevertheless I need to be able to do a few (up to 20) queries like this at the same time in in a fraction of second...: select pixel from raster where (x=X and y=Y). One query for each raster, representing a different information<br>
<br>If WKTRaster is mature enough, we can create a cluster without the need of paying a prohibitive license per CPU as for Oracle !<br><br>Sebastian<br><br><div class="gmail_quote">On Mon, Jul 19, 2010 at 5:00 PM, Pierre Racine <span dir="ltr"><<a href="mailto:Pierre.Racine@sbf.ulaval.ca" target="_blank">Pierre.Racine@sbf.ulaval.ca</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div link="blue" vlink="purple" lang="EN-US">
<div>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">Hi Sebastian,</span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);"> </span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">What kind of query are you planning on the raster? You know you
can also use WKT Raster to simply “register” filesystem rasters,
creating a king of geospatial catalog, without actually storing them in the
database…</span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);"> </span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">How many 16GB raster do you have? Are your raster all
representing the same theme? Are they overlapping (or they form a regular grid)?</span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);"> </span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">We don’t know of that many users cases up to now, but WKT
Raster prooved to be very stable working on 1 GB raster coverage (see the
tutorial).</span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);"> </span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);">Pierre</span></p>
<p class="MsoNormal"><span style="font-size: 11pt; color: rgb(31, 73, 125);"> </span></p>
<div style="border-width: medium medium medium 1.5pt; border-style: none none none solid; border-color: -moz-use-text-color -moz-use-text-color -moz-use-text-color blue; padding: 0cm 0cm 0cm 4pt;">
<div>
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<p class="MsoNormal"><b><span style="font-size: 10pt;">From:</span></b><span style="font-size: 10pt;">
<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>Sebastian
E. Ovide<br>
<b>Sent:</b> 19 juillet 2010 11:34<br>
<b>To:</b> PostGIS Users Discussion<br>
<b>Subject:</b> Re: [postgis-users] may have postgis store limits for a big
project?</span></p>
</div>
</div><div><div></div><div>
<p class="MsoNormal"> </p>
<p class="MsoNormal" style="margin-bottom: 12pt;">Hi All,<br>
<br>
I am interesting too... I am considering PostGIS+WKTRaster instead of Oracle
GeoRaster... but for that can happen, Postgresql must be able of managing some
simple tables of 30+M (Millions) rows plus a lot of Rasters of 16GB each...
(16GB not compress data... so are huge images !). Each query (simple look up)
must response in a fraction of second....<br>
<br>
any successful case ?<br>
<br>
Thanks !<br>
<br>
</p>
<div>
<p class="MsoNormal">On Fri, Jul 16, 2010 at 1:13 AM, salas <<a href="mailto:fsalas@geocuba.cu" target="_blank">fsalas@geocuba.cu</a>> wrote:</p>
<div>
<div>
<p class="MsoNormal"><span style="font-size: 10pt;">Hello
to all:<br>
I am working in a project where they are managed more than 20 geoespatials
thematics. Each thematic one has a considerable volume of since information it
is of the whole country (I am speaking of a lot more than a million of
records). In the project we need to make (mostly) intersection consultations
keeping in mind literal attributes.<br>
I need to know the experience of somebody in a project of this span and if
PostGIS would present some limitation therewith.</span></p>
</div>
<div>
<p class="MsoNormal"> </p>
</div>
<div>
<p class="MsoNormal"><span style="font-size: 10pt;">regards
yuriesky </span></p>
</div>
</div>
<p class="MsoNormal" style="margin-bottom: 12pt;"><br>
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</div>
<p class="MsoNormal" style="margin-bottom: 12pt;"><br>
<br clear="all">
<br>
-- <br>
Sebastian E. Ovide<br>
<br>
<br>
<br>
</p>
</div></div></div>
</div>
</div>
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<br></blockquote></div><br><br clear="all"><br>-- <br>Sebastian E. Ovide<br><br><br><br><br>