[postgis-users] RE: [postgis-devel] GML output

[Martin Daly]

strk,

> If think output size is a concern.

Then don't use XML..., or gzip the output.  XML parsers can typically
cope with gzip, or at least be modified to.

> Can't both namespace and srsName be written in a parent element ?

There are all sorts of ways to cope with namespaces, but for maximum
interoperability and transparency, I'd use gml: each time.  Our
(Cadcorp's) GML exporter puts the srsName= on the gml:Point,
gml:LineString, gml:Polygon, and gml:Multi-s, not on any of their
members (from memory it is even allowed on gml:coordinates).  That
seemed a reasonable compromise between just on the FeatureCollection,
and everywhere.

> Do you think postgis should 'flatten' nested collections 
> or keep them as they are ?

Flattening is annoying for systems that support the complex types - the
other properties are duplicated, or are wrong if pre-calculated, e.g.
area, etc. - but unavoidable to support systems that only support simple
types.  Not a choice I'm keen to make for you, I'm afraid.  You might
also find systems that support a single geometry type per
FeatureCollection, like with shapefile, but I guess a WHERE clause could
take care of that.

Regards,
Martin