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Hi all!<br>
<br>
I'm quite new to PostGIS but I think I'm learning rather quickly.
Anyways, I have a question regarding the storage of raster data in
PostGIS. First of all, I think the raster2psql utility is wondrous
and works great but unfortunately some of the data I need to store
as a raster comes to me in text format. Let's say I have the
latitude/longitude values and then the value of the raster in that
point which in this case, it'll be the swell.<br>
<br>
Thing is I've been loading this data to postGIS without any major
complication and then publishing that same info through geoserver.
Let me show you how I load the data to PostGIS:<br>
<br>
First,<br>
<blockquote><small>create table <tableName> (rid SERIAL
primary key, rast raster)</small><br>
<br>
</blockquote>
Then, for every row of data, <br>
<br>
<blockquote><small>insert into <tableName> (rast) select
ST_AddBand(ST_MakeEmptyRaster(1,1,<long>,
<lat>,1,1,0,0,4326), 1, '32BF', %s, 0.0)</small><br>
</blockquote>
<big>And,<br>
</big>
<blockquote><small>CREATE INDEX myrasters_rast_st_convexhull_idx ON
<tableName> USING gist( ST_ConvexHull(rast) );</small><br>
<small>SELECT AddRasterConstraints('<tableName>'::name,
'rast'::name);</small><br>
</blockquote>
<br>
This is all done in a python script and stores the data (I think)
correctly. I've got to admit that I still need to understand a
little bit more some of the parameters that are passed to the
AddBand and MakeEmptyRaster functions, but I can do it in my own,
this is not why I'm writing to you. The reason in fact, is that even
though GeoServer does show the data, it takes quite a lot to load,
and I thought it might be because I have not defined any overviews.
I've been trying to find how to do it, but all I see is references
to the raster2psql utility, but since I'm also a little new with
Python I don't know exactly what it does.<br>
<br>
So, after all this, my question would be how can I add overviews
"manually" to this raster data I'm loading? I would even appreciate
if you can tell me where in raster2psql.py I can find it, or if it
is in any other file it's being used for that purpose.<br>
<br>
Thank you very much for reading and I hope I was clear enough about
my issue :-)<br>
<br>
<pre class="moz-signature" cols="72">--
--
Mikel Gonzalez Gainza,
Informatikari bekaduna CENER-en // Becario informático en CENER
<a class="moz-txt-link-abbreviated" href="http://www.cener.com">www.cener.com</a></pre>
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