Geometry Viewer in pgAdmin 4 displays a straight line instead of polygons of European union countries

Question

Via PostGIS I import a shapefile layer with polygons of EU countries. I try select all rows and after still display blue straight line without the end. Where is the problem?

Answer 1

You probably need to change -- by using ST_Transform() -- the coordinate reference system (CRS) of your geometries, e.g. by using such query instead of a standard SELECT:

SELECT 
  ST_Transform(geom, 4326) AS geom_wgs84, -- adapt "geom" to fit the name of your geometry field if necessary 
  *
FROM mytable
-- WHERE ...;

if it's 3D geometry, they won't be rendered as well, so you need to use ST_Force2D():

SELECT
  ST_Transform(geom, 4326) AS geom_wgs84,
  ST_Force2D(ST_Transform(geom, 4326)) AS geom_2d_wgs84,
  *
FROM mytable
-- WHERE ...;

All this because of that:

When users click a feature in the map, a small pop-up will show up with its property table. If the SRID is 4326 (WGS84) the viewer will transform the coordinates to Web Mercator and add background tile layer.

Source: https://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XLII-4-W14/79/2019/isprs-archives-XLII-4-W14-79-2019.pdf