MySQL case

mysql> set @i=4;

 mysql> select case @i

    -> when @i>3 then'A'

    -> else 'B'

    -> end as t;

------------

mysql> select case

    -> when 5>4 then  'A'

    -> when 5<6 then 'B'

    -> else 'C'

    -> end as t;

+---+

select upper(case when 3> 2 then 'h' when 5>1 then 'e' else 'r' end) as Letter;

+--------+

| Letter |

+--------+

| H      |

+--------+