Folks: This topic I believe has been brought up before, but I thought I'd send an email since I'm a bit of a noob with POSTGIS. We have a large collection of Lidar points that I would like to perform spatial querying on (e.g. give me all points within a certain bounding box). The data (currently in LAS format, but easily loadable into the DB), is tiled up into smaller subsets. The data is x,y,z,intensity (and some other attributes that aren't so important) I have a few questions:
1) Should I load ALL of the LAS files into one massive table for querying (this is going to be a LOT of points). 2) If not, is there a trick where if I load up each LAS file into a separate table (which would, in theory be preferable since I'd like to do some testing before dealing with a database of this size), but somehow when I do a spatial query, the query can span multiple tables (e.g. say the query box is at the intersection of two adjacent tiles)? Related: what is the most efficient way to do a spatial query that effectively "rasterizes" this data, e.g. the min z value between x1 and x2, and y1 and y2, where x2-x1 and y2-y1 are the x and y pixel sizes? I'm not talking about interpolation, I'm talking an exact query. Thanks! --j -- Jonathan A. Greenberg, PhD Assistant Project Scientist Center for Spatial Technologies and Remote Sensing (CSTARS) Department of Land, Air and Water Resources University of California, Davis One Shields Avenue Davis, CA 95616 Phone: 415-763-5476 AIM: jgrn307, MSN: [email protected], Gchat: jgrn307 _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
