Hi

I am considering using Jena’s GEOSparql capabilities for storing and querying 
sailing maps (a map is a collection of features, and each feature has a 
geometry and other attributes (sea depth, quality of data metric, etc)).

Before I do that I was wanting to get a bit of advice to understand my options 
a bit:

a) can I use Jena’s GEOSparql stuff with both the feature set and the spatial 
index in memory? Can I have the index in mem and the data not, or vice-versa?

b) can I mix geometric and non-geometric conditions in one query (select 
features with some sort of geometry condition and some sort of non geometry 
condition).

c) a typical map has between 50K and 150K features (so that many geoms) — does 
anyone have any guess how big the spatial index will be for such a case?

d) how fast are the GEOSparql capabilities? I realize that is a bit of an open 
question, but experiments with spatial indexes in H2 in memory show that i can 
comfortably do a simple bounding box spatial query (so no other conditions) and 
get back 50K results in times of the order of seconds.

thanks
graham

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