1.dba_user表的password(除了GLOBAL和EXTERNAL的密码)不再保存密码。
查询10g的dba_user表
SQL> select username,password from dba_users; USERNAME PASSWORD ------------------------- ------------------------------ SYS 4CCF4A082AD3F312 SYSTEM 34F99ED804364129 GP BA5BE92FE6F36B67 REPADMIN 915C93F34954F5F8 HYY A7AEE33D853BFBC8 OUTLN 4A3BA55E08595C81 MGMT_VIEW 05CB73340B23910C MDSYS 72979A94BAD2AF80 ORDSYS 7EFA02EC7EA6B86F EXFSYS 66F4EF5650C20355 DMSYS BFBA5A553FD9E28A DBSNMP E066D214D5421CCC WMSYS 7C9BA362F8314299 CTXSYS 71E687F036AD56E5 ANONYMOUS anonymous SYSMAN 447B729161192C24 XDB 88D8364765FCE6AF ORDPLUGINS 88A2B2C183431F00 SI_INFORMTN_SCHEMA 84B8CBCA4D477FA3 OLAPSYS 4AC23CC3B15E2208 SCOTT F894844C34402B67 ORACLE_OCM 5A2E026A9157958C TSMSYS 3DF26A8B17D0F29F MDDATA DF02A496267DEE66 DIP CE4A36B8E06CA59C
查询11g的dba_user表
SQL> select username,password from dba_users; USERNAME PASSWORD ------------------------- ---------- SYSTEM SYS MGMT_VIEW DBSNMP SYSMAN ISC TEST LZQ SCOTT SURE SS OUTLN OLAPSYS SI_INFORMTN_SCHEMA OWBSYS ORDPLUGINS XDB ANONYMOUS CTXSYS ORDDATA OWBSYS_AUDIT APEX_030200 APPQOSSYS WMSYS EXFSYS ORDSYS MDSYS FLOWS_FILES SPATIAL_WFS_ADMIN_USR SPATIAL_CSW_ADMIN_USR APEX_PUBLIC_USER DIP MDDATA XS$NULL ORACLE_OCM 35 rows selected.
发现11g中password列值为空了。
这是因为虽然密码是经过加密存储的，但是从信息安全的角度来看，暴露的信息越多越不安全，所以即使是加密后的密码泄漏，也可能造成很严重的安全问题。所以作为11g的一个新特性，在dba_users的password列不再保存密码了。
那么问题就来了，如果我要做用户的迁移怎么办？呵呵，alter user identified by values依然可用。我们可以直接去查询sys.user$这张表。
SQL> select name,password from sys.user$ where name in (select username from dba_users); NAME PASSWORD ------------------------- ------------------------- SYSTEM 34F99ED804364129 SYS 4CCF4A082AD3F312 MGMT_VIEW 9F4137A5B1A2E1AC DBSNMP 10D93CA858E0F50D SYSMAN 4D4568914D47DF1D ISC 373F527DC0CFAE98 TEST 7A0F2B316C212D67 LZQ 8B8622D6B295E0E1 SCOTT F894844C34402B67 SURE 7CF462527540A5B0 SS 6C38D7B24909EB18 OUTLN 4A3BA55E08595C81 OLAPSYS 4AC23CC3B15E2208 SI_INFORMTN_SCHEMA 84B8CBCA4D477FA3 OWBSYS 610A3C38F301776F ORDPLUGINS 88A2B2C183431F00 XDB 88D8364765FCE6AF ANONYMOUS anonymous CTXSYS 71E687F036AD56E5 ORDDATA A93EC937FCD1DC2A OWBSYS_AUDIT FD8C3D14F6B60015 APEX_030200 6B653304BCFBC89D APPQOSSYS 519D632B7EE7F63A WMSYS 7C9BA362F8314299 EXFSYS 33C758A8E388DEE5 ORDSYS 7EFA02EC7EA6B86F MDSYS 72979A94BAD2AF80 FLOWS_FILES 738F2D4D10BF7DE2 SPATIAL_WFS_ADMIN_USR 7117215D6BEE6E82 SPATIAL_CSW_ADMIN_USR 1B290858DD14107E APEX_PUBLIC_USER E943E8C4CB4A6A9B DIP CE4A36B8E06CA59C MDDATA DF02A496267DEE66 XS$NULL DC4FCC8CB69A6733 ORACLE_OCM 5A2E026A9157958C rows selected.
事实上dba_users就是结合user$等相关基表创建的视图。从dba_uses视图的相关语句可以看出在11g中当用户被创建为全局或外部认证时password才有加密值，而10g中dba_users的password列完全取值与user$的password列值相关SQL
10g:
10g：
select u.name, u.user#, u.password,
m.status,
decode(u.astatus, , u.ltime,
, u.ltime,
, u.ltime,
, u.ltime,
, u.ltime,
, u.ltime, to_date(NULL)),
decode(u.astatus,
, u.exptime,
, u.exptime,
, u.exptime,
, u.exptime,
, u.exptime,
, u.exptime,
decode(u.ptime, '', to_date(NULL),
decode(pr.limit#, , to_date(NULL),
decode(pr.limit#, ,
decode(dp.limit#, , to_date(NULL), u.ptime +
dp.limit#),
u.ptime )))),
dts.name, tts.name, u.ctime, p.name,
nvl(cgm.consumer_group, 'DEFAULT_CONSUMER_GROUP'),
u.ext_username
from sys.user$ u left outer join sys.resource_group_mapping$ cgm
on (cgm.attribute = 'ORACLE_USER' and cgm.status = 'ACTIVE' and
cgm.value = u.name),
sys.ts$ dts, sys.ts$ tts, sys.profname$ p,
sys.user_astatus_map m, sys.profile$ pr, sys.profile$ dp
where u.datats# = dts.ts#
and u.resource$ = p.profile#
and u.tempts# = tts.ts#
and u.astatus = m.status#
and u.resource$ = pr.profile#
11g:
11g：
select u.name, u.user#,
decode(u.password, 'GLOBAL', u.password,
'EXTERNAL', u.password,
NULL),
m.status,
decode(u.astatus, , u.ltime,
, u.ltime,
, u.ltime,
, u.ltime,
, u.ltime,
, u.ltime, to_date(NULL)),
decode(u.astatus,
, u.exptime,
, u.exptime,
, u.exptime,
, u.exptime,
, u.exptime,
, u.exptime,
decode(u.ptime, '', to_date(NULL),
decode(pr.limit#, , to_date(NULL),
decode(pr.limit#, ,
decode(dp.limit#, , to_date(NULL), u.ptime +
dp.limit#),
u.ptime )))),
dts.name, tts.name, u.ctime, p.name,
nvl(cgm.consumer_group, 'DEFAULT_CONSUMER_GROUP'),
u.ext_username,
decode(length(u.password),,'10G ',NULL)||NVL2(u.spare4, '11G ' ,NULL),
decode(bitand(u.spare1, ),
, 'Y',
'N'),
decode(u.password, 'GLOBAL', 'GLOBAL',
'EXTERNAL', 'EXTERNAL',
'PASSWORD')
from sys.user$ u left outer join sys.resource_group_mapping$ cgm
on (cgm.attribute = 'ORACLE_USER' and cgm.status = 'ACTIVE' and
cgm.value = u.name),
sys.ts$ dts, sys.ts$ tts, sys.profname$ p,
sys.user_astatus_map m, sys.profile$ pr, sys.profile$ dp
where u.datats# = dts.ts#
and u.resource$ = p.profile#
and u.tempts# = tts.ts#
and u.astatus = m.status#
and u.resource$ = pr.profile#
2.密码区分大小写
可以通过初始化参数sec_case_sensitive_logon来控制密码是否大小写敏感，默认TRUE
3.密码复杂性检查
通过执行以下脚本生成密码复杂性检查函数verify_function_11G
@$ORACLE_HOME/RDBMS/ADMIN/utlpwdmg.sql
然后设置profile使用该函数来检查密码即可
ALTER PROFILE default PASSWORD_VERIFY_FUNCTION verify_function_11G;