UPDATE relation_types

SET label = (

SELECT string_agg(

CASE WHEN i = 1

THEN lower(left(p, 1)) || substr(p, 2)

ELSE upper(left(p, 1)) || substr(p, 2)

END, '' ORDER BY i)

FROM unnest(regexp_split_to_array(btrim(label), '[ _-]+'))

WITH ORDINALITY AS t(p, i)

WHERE p <> ''

)

WHERE label ~ '[ _-]';

UPDATE relation_types

SET label = lower(left(label, 1)) || substr(label, 2)

WHERE label ~ '^[A-Z]';