WITH Numbers AS
 (SELECT 90 as A, 2 as B UNION ALL
  SELECT 50, 8 UNION ALL
  SELECT 60, 6 UNION ALL
  SELECT 50, 10)
SELECT A, B,
  CASE A
    WHEN 90 THEN 'red'
    WHEN 50 THEN 'blue'
    ELSE 'green'
  END
  AS result
FROM Numbers

A

B

result

90

2

red

50

8

blue

60

6

green

50

10

blue