ALTER TABLE buildings ADD COLUMN IF NOT EXISTS extension_year smallint; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS developer_type varchar; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS designers varchar; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS designers_source_link text[]; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS designers varchar; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS lead_designer_type varchar; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS designer_awards boolean null; ALTER TABLE buildings ADD COLUMN IF NOT EXISTS awards_source_link text[];