[Featureserver] featureserver and dynamic layers?

[Christopher Schmidt]

On Fri, Mar 14, 2008 at 12:51:10PM +0100, Bud P. Bruegger wrote:
> Hi Josh,
>  
> > One thing that might help is if you can describe some specifics about 
> > the type of querying you need.  For example, I am planning to add 
> > something to the PostGIS datastore that will allow you to explicity 
> > state what kind of operator to use for matching in the queryable 
> > layers.   So then you could do something like 
> > &queryable=cost&cost__lessthan=15 ... this would translate to some SQL 
> > such as 'WHERE cost < 15'.   I would add support for just a few 
> > operators, but I think this could be powerful for a variety of cases 
> > (and would let me remove some ugly hacks I've added to some local fs 
> > projects).  So anyway, is this the type of thing you are thinking you 
> > are looking for when you say complex queries?  Or something else?
> 
> I confess that I don't have clear ideas on this myself--partly because
> I have to cover a large domain of yet unknown usecases ;-(
> 
> One thing that I would like for myself (and other super users) would be
> to shoot a full queury (any SQL string) to FS.  I suppose this is not
> what one wants to expose to the outside world though (or some or your
> friends), but would be nice to have...

I can't imagine a situation where this is useful that can't be solved in
other ways.

> On the side of the more controlled world, beyond what you had in mind it
> may be nice to have spatial constraints either relative to a geometry
> that is part of the query or relative to geometries in other layers.
> Examples that come in mind are these:

> * get me all trees that fall into buildings (we need to validate/clean
> tree data from one survey method and integrate them with the buildings
> originating from another)

This type of task is probably beyond the scope of FeatureServer. These
are general GIS tasks, better suited for work with data from
FeatureServer, passed through a filter in something like WPServer
( http://crschmidt.net/mapping/wpserverdemo/ )

> * get me all <features> that fall into a polygon (or multi-polygon)
> drawn in OpenLayers.  This is meant as a selection tool.

Typically, I think yu'd probably want to select all the features (so you
see them all) then select them within OpenLayers by building a
Javascript-level selection tool: then you can write code to update all
the features in your database. 

> Sorry for not having clearer ideas yet.  In the meantime I'll also look
> at the code of featureserever (is there an SVN or similar?)

Hm, I guess the 'SVN" link on the homepage isn't prominent enough? How
can I make it more prominent?

(It's at http://svn.featureserver.org/ , btw)

Regards,
-- 
Christopher Schmidt
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