[Mapserver-users] PHP/mapscript + PostGIS

[Vinko Vrsalovic]

On Fri, Apr 02, 2004 at 08:44:30PM +0100, Ruggero Valentinotti wrote:
> Hi list!
> I need to use PostGIS for some vector layers joined to other tables in my database...
> I'm using also several shapefile layers.
> Everything works fine except for these two functions when I try to query the PostGIS vector layers: 
> drawQuery()
> queryByShape()
> 
> I have built OID and GIST indexes on my tables.
> 
> 
> Things improves if I use drawQuery() on a single layer (active layer),
> but queryByShape() always fails.
 
I stumbled upon a similar problem. I reported it some weeks ago, but got
no response (probably because nobody understood me :-) ). My guess is
that MapScript's query functions are designed and built for shapefiles,
not for PostGIS layers.

I haven't had the time to dig deeper in the issue.
 
> I have found some messagges about these problems in the mapserver and postgis mailing lists,
> but I can't find a solution or a workaround...
 
 The workaround is to do the query in the DB, using SQL and the PostGIS
 operators, such as:

 SELECT * from mytable where mygeon && user_entered_geom_in_geo_units
 and
 intersects(mygeom,user_entered_geom_in_geo_units);

 (user_entered_geom_in_geo_units is, for instance, a GeomFromText('MULTIPOLYGON(...)',SRID))

If you need to draw the result, you can add the DB result as a new layer
to the mapObj

-- 
Vinko Vrsalovic <el[|- at -|]vinko.cl>
http://www.cprsig.cl