Oracle Create User And grant rights

CREATE USER WXG01
IDENTIFIED BY "WXG01"
DEFAULT TABLESPACE users
TEMPORARY TABLESPACE temp

GRANT DBA TO WXG01
GRANT UNLIMITED TABLESPACE TO WXG01

CREATE TABLE WXG_MESSAGE(

 MSG_CD CHAR(10),

 MSG_MONG VARCHAR2(200)

);

DROP USER username CASCADE;

SELECT 'DROP TABLE "' || TABLE_NAME || '" CASCADE CONSTRAINTS;' 
FROM user_tables;

begin
  for i in (select 'drop table '||table_name||' cascade constraints' tb from user_tables) 
  loop
     execute immediate i.tb;
  end loop;
  commit;
end;
purge RECYCLEBIN;