alter user identityName identified by password; —–修改密碼 alter user identityName account unlock; —–解鎖 alter user identityName account lock; —–加鎖 identityName:需要修改的用戶； password：新設密碼；

SQL> conn sys/sys as sysdbaConnected.SQL> show userUSER is "SYS"SQL> alter user hr account unlock;（解鎖）User altered.SQL> alter user hr identified by *password*;（更改密碼，這一步是必需的，否則hr模式還是不能使用的）User altered.到這里hr模式就可以使用了,試試：SQL> conn hr/*password*Connected.SQL> show userUSER is "HR"----------------------------------相反的SQL> alter user hr account lock;（上鎖）User altered.SQL> alter user hr password expire;（密碼失效）User altered.SQL> conn hr/*password*ERROR:ORA-28000: the account is lockedWarning: You are no longer connected to ORACLE.