I just recognized that our definition of GEOMETRY_COLUMNS does not declare that SRID is a foreign key linked to SRID in SPATIAL_REF_SYS. That seems like a potentially dangerous oversight. Does anyone see a problem if that restriction was *added*? Paul -- Paul Ramsey Refractions Research http://www.refractions.net pramsey at refractions.net Phone: 250-383-3022 Cell: 250-885-0632