Hi, I'm looking for a way to make EnvFunction used in filters play nice with databases and stores in general.
What happens now is that the function is not recognized and thus forces that part of the filter to be evaluated in memory. It would be nice to perform the param value expansion into a literal so that the store can use it for optimized filtering. A good place to perform the substitution is the SimplifyingFilterVisitor, which is already in use in a number of places. What we need to be sure about, though, is that the param value is not going to change on a feature by feature basis, which is not something we might not be able to take for granted... How do we deal with this? Add a "static" flag to the function where the use can declare if the function values are going to change during a data access? Or maybe add some global flag, some system variable, to declare the same? Imho the case of param values not changing feature by feature is the most common and having an optimization for it would be good, yet the dynamic case could be of interest as well Opinions? Cheers Andrea -- Andrea Aime OpenGeo - http://opengeo.org Expert service straight from the developers. ------------------------------------------------------------------------------ _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
