switch case mysql

select
CASE month 
when "01" then "January"
when "02" then "February"
when "03" then "March"
when "04" then "April"
when "05" then "May"
when "06" then "June"
when "07" then "July"
when "08" then "August"
when "09" then "September"
when "10" then "October"
when "11" then "November"
when "12" then "December"
END
from calendar where year = "2011" order by month