SELECT category FROM book_club WHERE YEAR  >  1989 GROUP BY category HAVING count(*)  >=  2
List categories that have at least two books after year 1989.
SELECT category FROM book_club WHERE YEAR > 1989 GROUP BY category HAVING count ( * ) > = 2
select category from book_club where year > value group by category having count ( * ) > = value
List categories that have at least two books after year 1989 .