Re: For Loop in PostGIS

I did some work to deal with this very issue. Take a look at this and
hopefully you will find it useful.

http://www.bostongis.com/PrinterFriendly.aspx?content_name=postgis_neare
st_neighbor_generic
<blocked::http://www.bostongis.com/PrinterFriendly.aspx?content_name=pos
tgis_nearest_neighbor_generic>

Hope that helps,
Regina

________________________________

From: pgsql-novice-owner(at)postgresql(dot)org
[mailto:pgsql-novice-owner(at)postgresql(dot)org] On Behalf Of Bryan Manuel
Sent: Tuesday, December 04, 2007 11:48 PM
To: pgsql-novice(at)postgresql(dot)org
Subject: [NOVICE] For Loop in PostGIS

I am new to postgresql and I'm working with two tables, both having a
geometry for postGIS. What I am trying to do is get the five nearest
people from one list for every person in the second. I was trying to do
this in a for loop - all I'm trying to do for now is display the 5
people for each person in the one list.

This code works as a command line argument to psql, and correctly finds
five people for one query:

select lastname, city from eng_alumni order by ST_distance(point_geom,
(select the_geom from points where text = 'Smith')) asc limit 5;

I tried to follow a for loop using the documentation, but it is not
working. This seems like something that a for loop would work well for,
at least in other languages that I have learned. Here is the code that
I tried (running from a command line)

create table temp;
FOR temp IN SELECT text, the_geom FROM points ORDER BY text LOOP
select lastname, latitude, longitude from eng_alumni order by
ST_distance(point_geom, (select the_geom from temp)) asc limit 5;
END LOOP;

Any help would be greatly appreciated.

Thanks,

Bryan Manuel

________________________________

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