Mine

CREATE TABLE configs (
    id SERIAL PRIMARY KEY,
    person_id integer references people(id),
    application TEXT not null,
    attribute TEXT not null,
    -- The value should be a simple value or a json string.
    -- Please create more config keys rather than abusing this with
    -- large datastructures.
    value TEXT,
    check (application in ('asterisk', 'moin', 'myfedora' ,'openid'))
    -- Might end up removing openid, depending on how far we take the provider
);