Reading the Same Selection from PostGIS Twice?

[Bill Thoen]

I want the layers separated because in this situation there's a WMS 
orthophoto layer that may appear above the filled polygons and below the 
county outlines. Although the performance hit is negligible in this case 
(apparently Linux is pretty good about caching), I just wondered if this 
could be an issue at times and if there was anything I could do about it.

Steve Lime wrote:
> If you have separate layers then you'll hit the server twice, yes. Why
> do you need them in separate layers? You certainly can achieve the visual
> effect (outlined polygons) within a single layer definition.
>
> Steve
>
>
>   
>>>> Bill Thoen <bthoen at GISNET.COM> 12/27/2006 2:43:57 PM >>>
>>>>         
> I've got a situation where I'm pulling the same selection of US county
>
> polygons from PostGIS in two LAYERs because I want filled polygons in a
>
> separate layer than the polygon outlines. I can make this work by 
> defining the same DATA selection statement for each LAYER, but doesn't
>
> this hit the PostGIS server twice? Is there a way to select the
> geometry 
> from the database once and then split the selection into separate 
> POLYGON type and LINE type layers within the MAP object?
>
>