Anne -
Some answers to your first question:
What is the relationship between the 'Simple feature access - Part 1:
Common architecture document and the 'GML simple features profile'
document? The latter references the GML spec, but how does the Common
Architecture document relate to those? And is there a Part 2?
Both of the standards mentioned above have their
"roots" in the ISO 19107: Spatial Schema standard. This ISO standard, originally
written by OGC Members, provides an abstract model for spatial geometry (points,
linestrings, polygons and many more) as well as the concept of a feature. A
feature is an observable phenomenon, such as a road or a fire
hydrant.
Simple features access (Parts 1, 2, 3, and 4) were
originally defined and approved by the OGC and subsequently ISO back in the
early 2000's. Part 2 if I remember correctly is Simple Features: SQL. This
standard defines a common query mechanism (including spatial queries) and
response payload (Well Known Types) for databases that support storage of
geospatial content. To date, most every commercial, commercial open source, and
open source database supports the Simple Features Standard. This includes
ORACLE, IBM DB2, Informix, SQL Server, PostGIS and so on. So Simple Features is
an interface standard. Simple Features 2.0 is in the works. The main changes
will be to add additional geometry types, such as NURBS, as well as full
harmonization with SQL MM and GML Simple Features.
The Geography Markup Language (GML) is an encoded
standard. GML was designed for sharing and communicating geospatial content. As
such, GML is also grounded in ISO 19107 as well as a number of other ISO
standards (such as for time, topology, and so forth). GML is content model
neutral and supports both geometry and feature models. GML Simple Features
profile is a profile of GML. A profile is a restricted subset of the full
schema. GML Simple Features is separate from Simple Features access - but both
are related in terms of their foundation in ISO 19107.
From an implementation perspective, there a number
of options on how to use Simple Features and/or GML. All depends on the use
cases.
My battery is running low!
More later.
Regards
Carl
----- Original Message -----
Sent: Thursday, February 17, 2011 11:27
PM
Subject: Re: [emix] Location and Bounded
Areas: GML Simple Features Profile
Hi Carl,
Thanks, and great to hear you'll be removing
the click-through!
Actually, yes, there were still a few questions I
had coming away from this:
a) What is the relationship between the
'Simple feature access - Part 1: Common architeture' document and the 'GML
simple features profile' document? The latter references the GML spec,
but how does the Common Architecture document relate to those? And is
there a Part 2?
b) Are there any other documents we should be looking
at given what you already know of our requirements, or is the GML simple
features profile the best for our use?
c) If we have questions during
review / implementation is it best to direct those to you or is there an email
discussion list for this on the OGC site?
d) and, of course ... when
will the schema be available?
Thanks so much for your time and
responses!
-Anne
creed@opengeospatial.org wrote, On
2/17/2011 8:08 PM:
c0239b9189ee08bf20fd93df0f153fe0.squirrel@mail.opengeospatial.org
type="cite">Anne -
Well done! Sometimes navigating the OGC web site can be a bit difficult.
And yes, we will be removing the click through license requirement in the
near future.
As a further FYI, GML Simple Features with the addition of Circle by
Center point has been approved for use by the Emergency Management TC for
use in a variety of EM related standards.
Also, a GML application schema is the location payload encoding used by
the IETF in numerous internet RFC's.
If you have any questions, please let me know!
Regards
Carl Reed
CTO
OGC
Following on to the discussion/request in today's EMIX meeting about
zeroing in on the ability to define bounded areas I took the recent
exchange on EI (
http://lists.oasis-open.org/archives/energyinterop/201101/msg00029.html
) and followed along through the wikipedia reference to the OGC site.
There is a Common Architecture document at
http://www.opengeospatial.org/standards under 'Simple Features' (scroll
down in left navigation panel, must do a click-through agreement to view
the spec). Being a very visually oriented person I started on page 23.
:) I think the geospatial elements in this document address our needs
around defining bounded areas, such as those used to define baseline
tariff areas/territories by the California PUC.
There is also a 'simple features profile' (click on 'Specification
Profiles' back at standards page) recently released and *approved for
OASIS use last month*
http://lists.oasis-open.org/archives/emergency/201101/msg00026.html also
attached to this email
http://lists.oasis-open.org/archives/emergency/201101/msg00007.html.
Supported GML geometric property types on page 21.
The referenced GML standard is here:
http://www.opengeospatial.org/standards/gml
Schema examples forthcoming:
http://lists.oasis-open.org/archives/emergency/201102/msg00003.html
Therer are many, many specs, profiles, etc on the OGC site so still
needs more sorting/investigation but this is a start for discussion.
-Anne