sql - compare 2 columns from different tables

Question

I have 2 tables with same column in each.. Lets call it colors. How do I compare the two to show the unique colors in table B that are not in table A?

Answer 1

select b.color
  from tbl1 b
 where not exists (select * from tbl2 a where b.color=a.color)

Answer 2

SELECT b.color AS color FROM tableB b
LEFT JOIN tableA a ON a.color = b.color
WHERE a.color IS NULL;