The question is basically: X db queries for each exploded layer vs 1 db query for a themed layer with X rules.
Theme rules require FDO filter evaluation of each feature (to resolve the matching theme rule used to stylize it) from the root query result. The root query result being a FDO query to the specified Feature Class and Feature Source as specified in the Layer Definition with the Layer Definition Filter applied if one is specified. If we go by the rule of thumb that anything that can be passed onto the datastore to figure out (filters/joins/etc) is faster than letting the FDO application layer (ie. MapGuide) figuring it out then a set of exploded layers would probably perform better than a themed one. Exploded themed layers (if you go by Maestro's definition) have no theme rules. They only have one. They also have a root query filter. Exploded theme layers have no overhead in filter evaluation (the data store figures that out), nor do they have any overhead on theme rule resolution (because exploded layers only have one rule). So I'll give a cheap cop-out answer: Let a performance profiler answer that question for you :) - Jackie -- View this message in context: http://osgeo-org.1560.x6.nabble.com/Sublayer-in-MG-tp5107090p5128666.html Sent from the MapGuide Users mailing list archive at Nabble.com. _______________________________________________ mapguide-users mailing list mapguide-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapguide-users