Minimal exmaple as per http://osgeo-org.1560.x6.nabble.com/Use-extra-columns-in-pycsw-admin-setup-db-td5323610.html
# ensure column exists in database table
mkdir pycsw/plugins/profiles/foo
touch pycsw/plugings/profiles/foo/__init__.py
cp foo.py pycsw/plugins/profiles/foo
python setup.py install
vi default.cfg
# add 'foo' to server.profiles option
# start pycsw