DCL_数据库控制语言

CREATE USER语句用于创建新用户
  CREATE USER user00                               
  IDENTIFIED BY user00; 

GRANT 权限 to user;
    系统权限
      create session
      create table
      create view
      create sequence...      
      grant create session to user00;
    对象权限   
      alter 
      delete
      select ..    
      grant select on student to user00;

revoke create session from user00;
      revoke select on student from user00;

alter user user00  IDENTIFIED by user000;

 drop user user00;

grant connect, resource to user000;

  grant user000 to user00;      -- 11g   分配权限 view synonym   10g okay
  revoke user000 from user00;
  drop role user000;

  sql Developer 工具 - 数据库导出
  cmd命令行 exp user50/user50@orcl file=f:/db.dmp
           imp user50/user50@orcl full=y file=f:/d
           imp hello/hello@orcl fromuser=user50 touser=hello file=f:/db.dmp