create user test identified by root;grant create session,resource to root;alter user test account unlock;grant create view to test;grant any sequece to test;grant create synonym to ich;--创建别名的权限drop user test cascade;连接时用户民不区分大小写alter system set sec_case_sensitive_logon=false scope=both;commit;修改用户密码alter user system identified by system; 

在用户1中建立的sequece test_seq如果想在用户2中使用(select test_seq.nextval from dual)必须现在用户2中执行select test_seq.nextval from dual;oracle一个创建用户、创建表空间、授权、建表的完整过程1. 用sys登录sql plus:    usename: sys as sysdba    password: ****2. 查看最大连接数： select value from V$parameter where name="processes";3. 查看当前连接数： select count (*) from V$process;4. 把最大连接数改成300：alter system set processes=300 scope=spfile5. 重启DB: shutdown immediate;                 startup;