CASE expression

   WHEN value_1 THEN result_1
   WHEN value_2 THEN result_2
   ...
   WHEN value_n THEN result_n

   ELSE result

END

#-------------------------------------------------------------

CASE

   WHEN condition_1 THEN result_1
   WHEN condition_2 THEN result_2
   ...
   WHEN condition_n THEN result_n

   ELSE result

END