Does Big Query support custom sorting?

Question

I am trying to sort data by applying case when statement in the order by clause but looks like Big Query doesn't support even though it worked fine in other SQL environments. Can somebody share your thoughts on this.

Answer 1

select x 
from (
  select x ,
  case when x = 'a' then 'z' else x end as y
  from 
    (select 'a' as x),
    (select 'b' as x),
    (select 'c' as x),
    (select 'd' as x)
  )
order by y desc