???????????
????scott????????????????????????????scott?????????
???????????????????
??????????????????:sqlplus(???)/nolog ???
??????????????????????conn sys/password as sysdba???
?????????????
?????????alter user scott identified by tiger;???
????alter user scott account unlock;???(??SCOTT????)
??????????????
?????? system ?????????????????????
????SQL>alter user scott account unlock;
?????????????
???????????????????????????????????????? scott ???????趨????
???????scott????????
????SQL>alter user scott identified by tiger;
?????????????
??????????????????? scott ?? tiger ????????????
????SQL>conn scott/tiger
???????????
?????? Oracle ??????????飺
????1. ??Dos?????????? sqlplus ????? Oracle ????? SQL Plus ??????????????????? sqlplus/nolog??? SQL Plus ?????????????
????2. ?? SQL Plus ?????? conn ????????????????е?????????
????SQL> conn ?????/???? ?磺 conn scott/tiger
????3. Oracle ?и??????????????????
????SQL> alter user ????? account lock; ????????
????SQL> alter user ????? account unlock; ????????
????????????????????? Oracle ????????????????
??????????Oracle ??scott ????????????????????????????????????????Oracle????????.