[postgis-users] hierarchical topology and attributes at different levels

[William Kyngesburye]

On Oct 21, 2012, at 2:40 PM, Sandro Santilli wrote:

> On Fri, Oct 19, 2012 at 11:56:18AM -0500, William Kyngesburye wrote:
> 
>> Can the attributes of child layers be seen from a layer? 
> 
> Sure, given enough neurons to build the appropriate SQL query...
> (TopoGeomeometry management still has rough edges)
> 
Yes, this has been taxing my neurons ;)

> It would be something like this:
> 
> SELECT * FROM child_features c, parent_features s
> WHERE id(c.topogeom) = GetTopoGeomElements(s.topogeom)[2];
> 
> Fixing the syntax is left as an excercise to the reader
> 
For now I'm interested in the possibilities.  I'm working on how I want to structure it and how to get the data in first.  I can get the base level of polys into topology, but I need to figure out how to connect higher level existing polygon data to the child levels (the states which are constructed from counties).  I guess when I figure that out, I'll know a lot more about how to do the query linking child-parent attributes.


-----
William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/

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First Pogril: I don't know either.  Wretched, isn't it?

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