PGHOST=foo.bar.com PGPASSWORD=jelszo pg
export PGHOST=foo.bar.com
export PGPASSWORD=jelszo
pg
pg --env ~/.foo.env (or pg --env foo if .foo.env is in the current directory.)
set -a
. .foo.env
set +a
pg
pg --sql "SELECT * FROM public.foo ;"
pg --dump ./foo.sql