Now we need a geometry column to populate. By default, the geometry column will be populated with null values. We populate a geometry column using the following query:
SELECT AddGeometryColumn ('chp02','xwhyzed1','geom',3734,'POINT',2);
We now have a column called geom with an SRID of 3734; that is, a point geometry type in two dimensions. Since we have x, y, and z data, we could, in principle, populate a 3D point table using a similar approach.
Since all the geometry values are currently null, we will populate them using an UPDATE statement as follows:
UPDATE chp02.xwhyzed1 SET the_geom = ST_SetSRID(ST_MakePoint(x,y), 3734);
The query here is simple when broken down. We update the xwhyzed1 table and set the the_geom column ...
