ALTER TABLE lesson_bookings ADD COLUMN sent_notices_at timestamp without time zone; ALTER TABLE lesson_bookings ADD COLUMN countered_at timestamp without time zone; ALTER TABLE lesson_sessions ADD COLUMN countered_at timestamp without time zone; ALTER TABLE lesson_bookings ADD COLUMN counterer_id VARCHAR(64) REFERENCES users(id); ALTER TABLE lesson_sessions ADD COLUMN counterer_id VARCHAR(64) REFERENCES users(id); ALTER TABLE lesson_bookings ADD COLUMN sent_counter_reminder BOOLEAN NOT NULL DEFAULT FALSE;