I think that this is an entirely correct result, as you are now getting it in the new units, which are degrees, rather than meters.
r.b. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Alan Cunnane Sent: Thursday, July 19, 2007 2:51 PM To: postgis-users@postgis.refractions.net Subject: [postgis-users] Distance query not working after transfrom? Im having a problem with a distance query after I transformed a set of points to another SRID. I transformed from easting northing (SRID 27700) to longitude lattitude (SRID 4326). The problem that I am having is that when I do the same distance queries using both geom columns I get a completely different result? I know that the distance query using the first easting northing column is correct. Here is an example of the different returns I am getting: SRID (27700): SELECT a.stop_reference, b.stop_reference, distance(a.east_north, b.east_north) FROM bus_stops1 a, bus_stops1 b WHERE a.stop_reference = 6200206290 AND b.stop_reference = 6200244450; stop_reference | stop_reference | distance ----------------+----------------+------------------ 6200206290 | 6200244450 | 4320.88972319359 SRID (4326): SELECT a.stop_reference, b.stop_reference, distance(a.googlemap, b.googlemap) FROM bus_stops1 a, bus_stops1 b WHERE a.stop_reference = 6200206290 AND b.stop_reference = 6200244450; stop_reference | stop_reference | distance ----------------+----------------+------------------- 6200206290 | 6200244450 | 0.041147965100606 Here is the table I am selecting from: Table "s0679212.bus_stops1" Column | Type | Modifiers ----------------+-----------------------+----------- stop_reference | character varying(12) | not null easting | integer | not null northing | integer | not null full_location | character varying(50) | gazetteer_code | character varying(1) | point_type | character varying(1) | nat_gazetteer | character varying(7) | district_name | character varying(24) | town_name | character varying(24) | east_north | geometry | not null lat | double precision | lon | double precision | googlemap | geometry | Indexes: "bus_stops1_pkey" PRIMARY KEY, btree (stop_reference) "stops_distance1" gist (east_north) Check constraints: "enforce_dims_east_north" CHECK (ndims(east_north) = 2) "enforce_dims_googlemap" CHECK (ndims(googlemap) = 2) "enforce_geotype_east_north" CHECK (geometrytype(east_north) = 'POINT'::text OR east_north IS NULL) "enforce_geotype_googlemap" CHECK (geometrytype(googlemap) = 'POINT'::text OR googlemap IS NULL) "enforce_srid_east_north" CHECK (srid(east_north) = 27700) "enforce_srid_googlemap" CHECK (srid(googlemap) = 4326) I created the googlemap column using these commands: SELECT AddGeometryColumn( 'bus_stops1', 'googlemap', 4326, 'POINT', 2 ); UPDATE bus_stops1 SET googlemap = transform(setsrid(makepoint(easting, northing),27700), 4326); Can anyone suggest what on earth could be wrong? _____ Yahoo! Mail is the world's favourite email. Don't settle for less, sign up for your free account today <http://uk.rd.yahoo.com/evt=44106/*http:/uk.docs.yahoo.com/mail/winter07 .html> .
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