On 10/16/07, Mark Leslie <[EMAIL PROTECTED]> wrote: > > Don Drake wrote: > > On 10/16/07, Mark Leslie <[EMAIL PROTECTED]> wrote: > >> Don Drake wrote: > >>> Here's my scenario, I have shapefiles containing polygons of > >> zipcodes. I > >>> have a table in Postgres that has a zip code with data that I would > like > >> to > >>> thematically map. I am not interested in loading the zipcodes into > >> PostGIS > >>> if I don't have to. I am using PHP/Mapscript, and I was wondering if > >> there > >>> is a way to merge the Postgres data with the shapefile layer on a map? > >>> > >>> Thanks. > >>> > >>> -Don > >>> > >> That depends what you mean by 'merge'. If you want to display both in > >> the same layer, you can come close by defining two layers in the same > >> group (see the GROUP item at > >> http://mapserver.gis.umn.edu/docs/reference/mapfile/layer). If you > want > >> to join the two sources together, Jeff has a nice example in the > >> reference docs > >> ( > >> > http://mapserver.gis.umn.edu/docs/reference/mapfile/join#example-2-join-from-shp-file-to-postgresql-table > >> ). > >> If I've missed the point entirely, then I'll need some more details > >> about what you're trying to end up with. > >> > >> > > > > Very interesting. It looks like the second link is close to what I > need, > > the first is not what I need. > > > > The thing is that the postgres table the data is coming out of does not > have > > a geometry column, the key is the zipcode. Furthermore, it will > probably > > come from a query, or a view. I tried using a view with no geometry and > > could not get it to work. The geometry will come from a shapefile. > > > > If this would work, could I color code using an expression? Is there a > > Mapscript alternative? > > > > Thanks. > > > > -Don > > > > If there's no geometry in the table, then the join is your only option > AFAIK. The downside is that joins are only intended for use in queries, > not in styling. I expect that since you're using MapScript, you could > execute a query to determine membership and dynamically setup the > styling, but that's a reasonably horrible solution. You'd be better of > using php to connect directly to postgres (http://au2.php.net/pgsql) to > find a zipcodes and set up your classes from that. Can I ask why you > don't want to load the zipcodes into PostGIS, or extract the table to > shapefile for that matter? Does the zipcode table change frequently? > > -- > Mark Leslie > Software Architect > LISAsoft Pty Ltd > www.lisasoft.com >
Loading the zipcodes into PostGIS is just a pain quite honestly. They're sitting in the filesystem for the entire country, I wish I could easily change the polygon color based on another attribute from a query from Postgres. I tried doing that using expressions, but it's not working, debugging mapscript is very frustrating. I'll be loading these into postGIS, thanks for your help. -Don
