Converting a text (lat/lon) to a point or geography

Question

In my table I have a column filled with text type lat/lon entries. I want to convert these entries to a point? Or something I can use with PostGIS functions

I am aware of SELECT ST_PointFromText('POINT(-71.064544 42.28787)', 4326);, but it does not work when I try to do SELECT ST_PointFromText('POINT('locdata.loc_geo')', 4326) from locdata

That just gets me this error: ERROR: syntax error at or near "locdata" LINE 1: SELECT ST_PointFromText('POINT('locdata.loc_geo')',.

Extra info: my locdata.loc_geo entries are text entries structured like this: 34.032601, 78.551298 (the order doesnt matter, i dont need an exact place, just get the math working)

Answer 1

The error occurs because stitching two objects (literal string or column) requires a concatenation operator, like SELECT ST_PointFromText('POINT(' || locdata.loc_geo ||')', 4326) from locdata

But it won't work either because of the coma and the lat-long swap. Instead, you can read the coordinates, split them in an array, cast it to floats (or double), then construct the point using the coordinates:

WITH split_src AS (
  SELECT string_to_array(loc_geo, ', ')::float[]  arr
  FROM locdata)
SELECT st_asText(st_makePoint(arr[2],arr[1])) 
FROM split_src;