sql - Query a column and change value to numeric value -

i using sql server 2012. have table contains column mycol can 4 values below:

mn abb bo  bn 

when query data table want change these values numeric value instead, mn = 1, abb = 2, bo = 3 & bn = 4.

how do using select statement?

simple case statement do:

select     case mycol        when 'mn' 1        when 'abb' 2        when 'bo' 3        when 'bn' 4     end     dbo.yourtable