On Fri, Mar 17, 2006 at 11:41:11PM -0500, Tom Lane wrote: > Dan Harris <fbsd@xxxxxxxxxxxxxxx> writes: > > Furthermore, by doing so, I am tying my queries directly to > > "postgres-isms". One of the long term goals of this project is to be > > able to fairly transparently support any ANSI SQL-compliant back end > > with the same code base. > > Unfortunately, there isn't any portable or standard (not exactly the > same thing ;-)) SQL functionality for dealing gracefully with > two-dimensional searches, which is what your lat/long queries are. The OpenGIS Simple Features Specification[1] is a step in that direction, no? PostGIS[2], MySQL[3], and Oracle Spatial[4] implement to varying degrees. With PostGIS you do have to add non-standard operators to a query's predicate to benefit from GiST indexes on spatial columns, but the rest of the query can be straight out of the SQL and OGC standards. [1] http://www.opengeospatial.org/docs/99-049.pdf [2] http://www.postgis.org/ [3] http://dev.mysql.com/doc/refman/5.0/en/spatial-extensions.html [4] http://www.oracle.com/technology/products/spatial/index.html -- Michael Fuhr
