text: CREATE USER user1 with PASSWORD  'wang@123';
  CREATE USER user2 with PASSWORD  'wang@123';
  SET ROLE user1 PASSWORD 'wang@123';
  --can not drop schema user2 in General user
  DROP SCHEMA user2;
  --can not drop user user2 in General user
  DROP USER user2;
  --can not grant user1 to sysadmin user
  GRANT ALL PRIVILEGES TO user1;
  RESET ROLE;
  --grant user1 to sysadmin user
  GRANT ALL PRIVILEGES TO user1;
  SET ROLE user1 PASSWORD 'wang@123';
  --success drop schema 
  DROP SCHEMA user2;
  --success drop user;
  DROP USER user2;
  RESET ROLE;
  REVOKE ALL PRIVILEGES FROM user1;
  DROP USER user1 ;
  