sqlplus /nolog
　　回车后，将出现提示符 SQL>
　　这时输入
　　conn / as sysdba

select name from v$datafile;
　　windows下可能看到的结果如下：
　　SQL> select name from v$datafile;
　　NAME
　　--------------------------------------------------------------------------------
　　D:\oracle\oradata\orcl\system01.dbf
　　D:\oracle\oradata\orcl\undotbs01.dbf
　　D:\oracle\oradata\orcl\cwmlite01.dbf
　　D:\oracle\oradata\orcl\drsys01.dbf
　　D:\oracle\oradata\orcl\indx01.dbf
　　D:\oracle\oradata\orcl\tools01.dbf

SQL> select name from v$datafile;
　　NAME
　　--------------------------------------------------------------------------------
　　/oracle/oradata/orcl/system01.dbf
　　/oracle/oradata/orcl/undotbs01.dbf
　　/oracle/oradata/orcl/cwmlite01.dbf
　　/oracle/oradata/orcl/drsys01.dbf
　　/oracle/oradata/orcl/indx01.dbf
　　/oracle/oradata/orcl/tools01.dbf

create tablespace 表空间名 datafile  '对应的文件名'  size  大小;

create tablespace yang datafile 'D:\oracle\oradata\orcl\yang.dbf' size 3000m;

create tablespace yang datafile '/oracle/oradata/orcl/yang.dbf' size 3000m;

create user 用户名 identified by 密码 default tablespace 用户默认使用哪一个表空间;

grant 角色1,角色2 to 用户名;

create user yanglei identified by yang123 default tablespace yang;
　　grant dba, connect to yanglei;

-- Create the user 
create user MEP
 identified by whq1987
 default tablespace MEP
 temporary tablespace MEP_TEMP
 profile DEFAULT;
-- Grant/Revoke role privileges 
grant connect to MEP;
grant datapump_exp_full_database to MEP;
grant datapump_imp_full_database to MEP;
grant dba to MEP;
grant exp_full_database to MEP;
grant imp_full_database to MEP;
grant resource to MEP;
-- Grant/Revoke system privileges 
grant alter_user to MEP;
grant comment any table to MEP;
grant create any view to MEP;
grant create session to MEP;
grant create user to MEP;
grant delete any table to MEP;
grant drop user to MEP;
grant export full database to MEP;
grant unlimited tablespace to MEP;