张金伟jwzhangaust.edu数据库应用系统开发本书采用的主机字符串为orcl本书将SYS和SYSTEM用户口令分别设置为syspwdsystempwd在SQLPlus中执行如下命令:CONN orcl AS SYSDBAALTER USER SYS IDENTIFIED BY syspwdALTER USER SYSTEM IDENTIFIED BY systempwd1.主机字符串