1

I have some MultiPolygon geometries in SRID 4258 and am trying to transform them into SRID 4326. When I run the following command, however, the output still seems to be in SRID 4258.

Command:

SELECT ST_AsText(ST_Transform(ST_Centroid(geom), 4326)) 
FROM   geoms_to_convert 
LIMIT  1

Ouput:

POINT(3819288.74433993 3132617.8860223)

I am converting to a point to see if the transform works, and the end goal is to have the point return in lat and long.

I don't see what I am doing wrong and am relatively new to PostGIS. I have confirmed that both projections are present in the spatial_ref_sys table and am using PostGIS version 2.4.

  • 1
    Can you post your geom in WKT format? – rughimire May 4 at 5:37
  • 1
    What is the original srid of your layer? Can it be 0 (non georeferenced)? Check srid in geometry_columns view. – Zoltan May 4 at 6:10
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EPSG:4258 http://epsg.io/4258 is using degrees as units. Point POINT(3819288.74433993 3132617.8860223) cannot be in either EPSG:4258 or EPSG:4326.

Another thing is that for Proj the both EPSG codes are equivalent

gdaltransform -s_srs epsg:4326 -t_srs epsg:4258
Enter X Y [Z [T]] values separated by space, and press Return.
20 65
20 65 0

Proj has now methods in for taking the temporal shift of land masses into account but then you should also define the imes of the realisation. There is some info in https://proj.org/usage/transformation.html.

However, the conclusion is that for normal GIS users EPSG:4326 and EPSG:4258 mean the same.

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