Hello,
I am looking to simplify this query (uses PostGIS, but I have encountered this
scenario with other chains of functions):
gtest=# SELECT X( SetSRID( Transform( GeomFromText( 'POINT(142512 1020225)', 26910 ), 4326 ), -1)
) as xcoord, Y( SetSRID( Transform( GeomFromText( 'POINT(142512 1020225)', 26910 ), 4326 ), -1)
) AS ycoord;
This SELECT works, but the rather long arguments to X(geom) and Y(geom) are
the same. Is it possible and feasible to pre-calculate the argument, such
as:
gtest=# SELECT SetSRID( Transform( GeomFromText( 'POINT(142512 1020225)', 26910 ), 4326 ), -1) AS
transformed_geom,X(transformed_geom) AS xcoord, Y(transformed_geom) AS ycoord
Where I don't really care about transformed_geom being returned, but it saves
double-calling the inside functions This doesn't work -- it complains that
transformed_geom is not a column.
SELECT version(); gives:
PostgreSQL 8.0.6 on i386-portbld-freebsd5.4, compiled by GCC cc (GCC) 3.4.2
[FreeBSD] 20040728
Thanks in advance!
Mike.
--
Michael Burke
Engineering Technologies Canada Ltd.
michael@engtech.ca 1 (902) 628-1705