SQL> with 
  2    data as (
  3      select trim(to_char(trunc(sysdate, 'WW')+level-1,'Day')) d, 
  4             level n
  5      from dual
  6      connect by level <= 7
  7    )
  8  select sys_connect_by_path(d,' ') weekdays
  9  from data
 10  where n = 7
 11  connect by prior n = n-1
 12  start with n = 1
 13  /
WEEKDAYS
----------------------------------------------------------------
 Lundi Mardi Mercredi Jeudi Vendredi Samedi Dimanche

1 row selected.