[postgis-users] subquery on a postgis layer

[toni hernnadez]

I have several tables related with the urban planning in my town.
Two of these tables are:
Urban Soil 2006, and green areas 1992. Both have a geom field called 
"geom" and some other alfanumeric fields. There is no relation between 
these two tables.

I would like to show the intersection of these two layers to show which 
green areas have turn into urban soil.
I haven't either UNION nor JOIN. The thing is I don't know if this is 
possible and if so.. how to do it.
Thanks


Markus Schaber wrote:

>Hi, Toni,
>
>toni hernnadez wrote:
>
>  
>
>>Is it possible to use the intersection function (or any other spacial
>>postgis function) on two postgis tables with  a  postgis layer on
>>mapserver?
>>    
>>
>
>Yes, it should be, but it's possible that you need to create a view and
>appropriate geometry_columns entry.
>
>For proper help, we need more details (do you UNION, JOIN or sub-SELECT
>the two tables together, what should intersect etc.).
>
>HTH,
>Markus
>  
>