urlencode with only built-in functions

Question

Without using plpgsql, I\'m trying to urlencode a given text within a pgsql SELECT statement.

The problem with this approach:

select regexp_replace(\         


        

Answer 1

select regexp_replace(encode('héllo there','hex'),'(..)',E'%\\1','g');

This doesn't leave the alphanumeric characters human-readable, though.