Spatial Xml Db
A few years ago there was a lot of interest in native xml databases. But not much recently. ESRI mentioned supporting “feature level metadata”, but not sure what happened there either. If they did do that, I’m sure the next thing people will want is a way to query features in a featureclass based using XQuery instead of Sql. Seems like it should be possible to write a custom layer XmlLayer (that implements ILayer) and provides something a bit more xml-centric.
In addition to questioning whether spatial is indeed special, maybe we should be more general and ask if the relational database model is always best for geospatial datasets. This becomes apparent to me when I think about feature level metadata. One man’s metadata is another man’s data. If ESRI stores metadata in a bag hanging off the side of each feature, people will have difficulty querying it. Perhaps ESRI should push for an OGC standard for spatial XQueries of native XML databases, then write wrappers so that tabular (georelational) featureclasses could appear as if they were bona fide Xml documents, and therefore XQueryable.
FUD factor: if ESRI doesn’t do this maybe Google will. I really would like to upload my cross – town commute as a polyline into google so that I could search for products sold by stores that I drive past. This would be yet another ad revenue stream for Google.