How does one generate an upper and lowercase alphanumeric random string from oracle?
I have used select DBMS_RANDOM.STRING(\'x\', 10) from dual to generate          
        
Try this,
with
  r as (
    select
      level lvl,
      substr(
        'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789',
        mod(abs(dbms_random.random), 62)+1, 1) a
    from dual connect by level <= 10
  )
select
  replace(sys_connect_by_path(a, '/'), '/') random_string
from r
where lvl = 1
start with lvl = 10
connect by lvl + 1 = prior lvl
;
Output,
FOps2k0Pcy