There are several methods for creating geometries in a database:
INSERT INTO world_cities( country, city, point )
SELECT country, city, NEW ST_Point( longitude, latitude, 4326 )
FROM OPENSTRING( FILE 'capitalcities.csv' )
WITH(
country CHAR(100),
city CHAR(100),
latitude DOUBLE,
longitude DOUBLE )
ALTER TABLE my_table ADD point AS ST_Point(SRID=4326) COMPUTE( NEW ST_Point( longitude, latitude, 4326 ) );