CSW

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From Raj Singh:

The document I'll call CSW is available here: OpenGIS© Catalogue Service Implementation Specification 2.0.2 available here: <http://www.opengeospatial.org/standards/cat> or direct link: <http://portal.opengeospatial.org/files/? artifact_id=20555>

I'm going to explain how a *subset* of CSW fulfills the desires of this group, IMHO. Now this document begins with a very abstract description of how to build a catalog. Lost in here, is a very useful specification of a basic catalog in Chapter 10.

The key portions of this chapter are:

  • 1. an information model, <csw:Record>, that uses key Dublin Core terms (mapping shown in attached graphic, or in Table 53 on page 119 of the document). There's an example of a <csw:Record> here: < http://schemas.opengis.net/csw/2.0.2/examples/ Clause_10.2.5.3.2_Example03_Full.xml >


  • 2. a small addition to DC to get a bounding box in there. I quote,
"The full record is based on the XML schemas developed for the Dublin
Core MetaInitiative with the addition of the csw:AnyText and
ows:BoundingBox elements" (page 119).
  • 3. a query mechanism -- CQL. CQL is a SQL-like language whose utility hasn't been seen because it is so poorly documented and described. Here are some good links:
http://zing.z3950.org/cql/intro.html
http://docs.codehaus.org/display/GEOTDOC/01+CQL+Examples

There's a *lot* of other stuff in CSW, but I think some "dclite" that used these 3 things -- or even dropped 3 in favor of an OpenSearch, template-based search mechanism -- would gain momentum in our community.

Csw table53.png

See Also