当ORACLE数据库系统启动后，数据字典总是可用，它驻留在SYSTEM表空间中。数据字典包含视图集，在许多情况下，每一视图集有三种视图包含有类信息，彼此以前缀相区别，前缀为USER、ALL和DBA。 l前缀为USER的视图，为用户视图，是在用户的模式内。 l前缀为ALL的
当ORACLE数据库系统启动后，数据字典总是可用，它驻留在SYSTEM表空间中。数据字典包含视图集，在许多情况下，每一视图集有三种视图包含有类似信息，彼此以前缀相区别，前缀为USER、ALL和DBA。
l 前缀为USER的视图，为用户视图，是在用户的模式内。
l 前缀为ALL的视图为扩展的用户视图（为用户可存取的视图）。
l 前缀为DBA的视图为DBA的视图（为全部用户可存取的视图）。
在数据库ORACLE还维护了一组虚表（virtual table）记录当前数据库的活动，这些表称为动态性能表。动态性能表不是真正的表，许多用户不能直接存取，DBA可查询这些表，可以建立视图，给其它用户授予存取视图权。
ORACLE数据字典与视图
|
视 图 名 |
说 明 |
|
ALL_CATALOG |
为用户可存取的全部表、视图和序列 |
|
ALL_COL_COMMENTS |
为用户可存取的表和视图列上的注释 |
|
ALL_COL_PRIVS |
在列上授权，该用户或PUBLIC是被授与者 |
|
ALL_COL_PRIVS_MADE |
在列上授权，该用户为持有者或授与者 |
|
ALL_COL_PRIVS_RECD |
在列上授权，该用户或PUBLIC是被授与者 |
|
ALL_CONSTRAINTS |
在可存取表上的约束定义 |
|
ALL_CONS_COLUMN |
关于在约束定义中可存取列的信息 |
|
ALL_DB_LINKS |
用户可存取的数据库链 |
|
ALL_DBF_AUDIT_OPTS |
在对象建立时，所应用的缺省对象审计选择 |
|
ALL_DEPENDENCIES |
用户可存取的对象之间的从属关系 |
|
ALL_ERROES |
在用户可存取对象上的当前错误 |
|
ALL_INDEXES |
在用户可存取的表上的索引说明 |
|
ALL_IND_COLUMNS |
在可存取的表上的索引列 |
|
ALL_OBJECTS |
用户可存取的对象 |
|
ALL_SEQUENCES |
用户可存取的序列说明 |
|
ALL_SNAPSHOTS |
用户可存取的全部快照 |
|
ALL_SOURCE |
用户可存取的全部存储对象文本源程序 |
|
ALL_SYNONYM |
用户可存取的全部同义词 |
|
ALL_TABLES |
用户可存取的表的说明 |
|
ALL_TAB_COLUMNS |
用户可存取的表、视图、聚集的列 |
|
ALL_TAB_COMMENTS |
用户可存取的表或视图上的注释。 |
|
ALL_TAB_PRIVS |
在对象上授权，该用户或PUBLIC被授与者 |
|
ALL_TAB_PRIVS_MADE |
在对象上的授权或用户授权 |
|
ALL_TAB_PRIVS_RECD |
在对象上授权，该用户或PUBLIC是被授与者 |
|
ALL_TRIGGERS |
用户可存取的触发器 |
|
ALL_TRIGGER_COLS |
显示用户持有的表中的列和用户所持有的触发器中列的使用，或者用户具有CREATE ANY TRIGGER特权时在所有触发器上列的使用 |
|
ALL_USERS |
关于数据库是所有用户的信息 |
|
ALL_VIEW |
用户可存取的视图文本 |
|
AUDIT_ACTIONS |
审计跟踪动作类型代码描述表 |
|
CAT |
为USER_CATALOG的同义词 |
|
CHAINED_ROWS |
ANALYZE CHAINED ROWS命令的缺省值 |
|
CLU |
为USER_CLUSTERS的同义词 |
|
COLS |
为USER_TAB_COLUMNS的同义词 |
|
COLUMN_PRIVILEGES |
在列上授权，用户是其授权者，被授与权者、持有者或授与PUBLIC |
|
DBA_2PC_NEIGHBORS |
关于悬挂事务入和出连接的信息 |
|
DBA_2PC_PENDING |
关于在PREPARED状态时失败的分式事务信息 |
|
DBA_AUDIT_EXISTS |
由AUDIT EXISTS命令建立的审计跟踪记录 |
|
DBA_AUDIT_OBJECT |
系统中全部对象的审计跟踪记录 |
|
DBA_AUDIT_SESSION |
系统中涉及CONNECT和DISCONNECT的全部审计跟踪记录 |
|
DBA_AUDIT_STATEMENT |
系统中涉及GRANT、REVOKE、AUDIT、NOAUDIT和ALTER SYSTEM语句的全部审计记录 |
|
DBA_AUDIT_TRAIL |
为系统中全部审计记录的集合 |
|
DBA_BLOCKERS |
为会话集，它们具有别的会话正等待的一封锁，而它们本身不等待封锁 |
|
DBA_CATALAOG |
为全部数据库表、视图、同义词和序列 |
|
DBA_CLUSTERS |
数据库中全部聚集的说明 |
|
DBA_CLU_CLOUMNS |
表列对聚集列的映射 |
|
DBA_COL_COMMENTS |
在所有表和视图的列上的注释 |
|
DBA_COL_PRIVS |
在数据库列上的全部授权 |
|
DBA_CONSTRAINTS |
在数据库全部表上的约束定义 |
|
DBA_CONS_CLOUMNS |
关于约束定义中全部列的信息 |
|
DBA_DATA_FILES |
关于数据文件的信息 |
|
DBA_ DB_LINKS |
在数据库中的全部数据链 |
|
DBA_ DDL_LOCKS |
数据库中当前所有全部DDL封锁和所有未完成的DML封锁请求 |
|
DBA_ DEPENDENCIES |
全部对象之间的从属关系 |
|
DBA_DML_LOCKS |
数据库中当前所持有DDL封锁和所有未完成的DML封锁请求 |
|
DBA_ERRORS |
数据库中全部存储对象上的当前错误 |
|
DBA_EXP_FILES |
输出文件说明 |
|
DBA_EXP_OBJECTS |
已有增量输出的对象 |
|
DBA_EXP_VERSION |
最后的输出会话的版本 |
|
DBA_EXTENTS |
数据库中全部段的范围 |
|
DBA_FREE_SPACE |
在所有表空间中未用的范围 |
|
DBA_INDEXES |
数据库中全部索引的说明 |
|
DBA_IND_COLUMN |
全部表和聚集上的索引列 |
|
DBA_LOCKS |
在数据库中持有的全部封锁和未完成请求的封锁（包括DML和DDL封锁） |
|
DBA_OBJECT |
在数据库中定义的全部聚集、数据库链、索引、包、包体、序列、同义词、表和视图 |
|
DBA_OBJECT_SIZE |
数据库中的全部PL/SQL对象 |
|
DBA_OBJ_AUDIT_OPTS |
为全部表和视图的审计选择 |
|
DBA_PRIV_AUDIT_OPTS |
特权审计选择 |
|
DBA_PROFILES |
赋给每个环境文件的资源限制 |
|
DBA_ROLES |
在数据库中已有的全部角色 |
|
DBA_ROLE_PRIVS |
授权给用户或角色的角色的说明 |
|
DBA_ROLLBACK_SEGS |
回滚段的说明 |
|
DBA_SEGMENTS |
分配给全部数据库段的存储 |
|
DBA_SEQUENCES |
在数据库中全部序列的说明 |
|
DBA_SNAPSHOTS |
在数据库中的全部快照 |
|
DBA_SNAPSHOTS_LOGS |
在数据库中的全部快照日志 |
|
DBA_SOURCE |
在数据库中全部存储对象的源文本 |
|
DBA_SYNONYMS |
在数据库中的全部同义词 |
|
DBA_STMT_AUDIT_OPTS |
为当前系统审计选择 |
|
DBA_SYS_PRIVS |
授权给用户或角色的系统特权 |
|
DBA_TABLES |
在数据库中的全部表的说明 |
|
DBA_TABLESSPACES |
数据库中的全部表空间的说明 |
|
DBA_TAB_CLOUMNS |
全部表、视图和聚集中的列 |
|
DBA_TAB_COMMENTS |
在数据库中全部表和视图上的注释 |
|
DBA_TAB_PRIVS |
在数据库中对象上的全部授权 |
|
DBA_TRIGGERS |
在数据库中全部触发器的说明 |
|
DBA_TRIGGERS_COLS |
显示由用户定义或在任何用户表上的触发器中列的用法 |
|
DBA_TS_QUOTAS |
为全部用户的表空间份额 |
|
DBA_USERS |
关于数据库全部用户的信息 |
|
DBA_VIEWS |
数据库中全部视图的文本 |
|
DBA_WAITERS |
等待封锁的全部会话和持有该锁的会话 |
|
DICT |
为DICTIONARY的同义词 |
|
DICTIONARY |
数据库字典表和视图的说明 |
|
DICT_COLUMNS |
数据库字典表和视图中的列的说明 |
|
EXCEPTIONS |
违反完整性约束的信息 |
|
GLOBAL_NMAE |
当前数据库的全局名 |
|
IND |
为USER__INDEXES的同义词 |
|
INDEX_STATE |
存储VAILDATE INDEX命令的信息 |
|
OBJ |
为USER_ OBJECT的同义词 |
|
RESOURCE_COST |
每种资源的费用 |
|
ROLE_ROLE_PRIVS |
授权给其它角色的角色的信息 |
|
ROLE_SYS_PRIVS |
授权给角色的系统特权的信息 |
|
ROLE_TAB_PRVS |
授权给角色的表特权的信息 |
|
SEQ |
为USER_SEQUENCES的同义词 |
|
SEESSIONS_PORIVS |
用户当前可用的特权 |
|
SESSION_ROLES |
用户当前已使其使能打角色 |
|
SYN |
为USER_SYNONYMS的同义词 |
|
SYSTEM_PRILEGE_MAP |
为系统特权代码的说明表 |
|
TABLE_PRIVILEGES |
在对象上授权 |
|
TABLE_PRIVILEGE_MAP |
为存取特权代码的说明表 |
|
TABS |
为USER_TABLES的同义词 |
|
USER_AUDIT_OBJECT |
涉及对象审计跟踪记录 |
|
USER_AUDIT_SESSION |
涉及连接或删除连接的全部审计跟踪记录 |
|
USER_AUDIT_STATEMENT |
为用户发出的GRANT、REVOKE、AUDIT、NOAUDIT、ALL SYSTEM语句的审计跟踪项 |
|
USER_AUDIT_TRAIL |
与用户有关的审计跟踪项 |
|
USER_CATALOG |
为用户所持有的表、视图、同义词和序列 |
|
USER_CLUSTERS |
为用户持有的聚集的说明 |
|
USER_CLU_CLOUMNS |
用户的表列到聚集的映射 |
|
USER_COL_COMMENTS |
在用户的表或视图的列上的注释 |
|
USER_COL_PRIVS |
在列上的授权，该用户是持有者、授权者或被授与者 |
|
USER_COL_PRIVS_MADE |
为用户持有的对象的列上的全部授权 |
|
USER_COL_PRIVS_RECD |
该用户是被授权者的列上的授权 |
|
USER_CONSTRAINT |
在用户表上的约束定义 |
|
USER_CONS_COLUMNS |
由用户持有约束定义中的列的信息 |
|
USER_DB_LINKS |
为用户持有的数据库链 |
|
USER_DEPENDENCIES |
用户的对象之间的从属关系 |
|
USER_ERRORS |
用户的存储对象上的当前错误 |
|
USER_EXTRNTS |
属于用户对象的段的范围 |
|
USER_FREE_SPACE |
用户可存取的表空间中未用的范围 |
|
USRE_INDEXES |
用户自己的索引说明 |
|
USER_IND_CLOUMNS |
用户索引的列或用户表上的列 |
|
USER_OBJECTS |
用户所持有的对象 |
|
USER_OBJECT_SIZE |
用户的PL/SQL对象 |
|
USER_OBJ_AUDIT_OPTS |
为用户的表和审计选择 |
|
USER_RESOURCE_LIMITS |
为当前用户的资源限制 |
|
USER_ROLE_PRIVS |
特权给用户的角色 |
|
USER_SEGMENT |
属于用户对象的数据库段的存储分配 |
|
USER_SEQUENCE |
用户自己的序列的说明 |
|
USER_SNAPSHOTS |
用户可查看的快照 |
|
USER_SNAPSHOT_LOGS |
用户可持有的快照日志 |
|
USER_SOURCE |
属于用户的全部存储对象的源文本 |
|
USER_SYNONYM |
用户专用同义词 |
|
USER_SYS_PRIVS |
特权给用户的系统特权 |
|
USER_TABLES |
用户持有表的说明 |
|
USER_TABLESPACES |
可存表空间的说明 |
|
USER_TAB_COLUMNSS |
用户的表、视图和聚集的列 |
|
USER_TAB_COMMENTS |
用户所持的表和视图上的注释 |
|
USER_TAB_PRIVS |
用户为授权者、持有者或被授权者的对象上的授权 |
|
USRE_TAB_PRIVS_MADE |
用户所持有的对象的全部特权 |
|
USER_TAB_PRIVS_RECD |
用户为被授权者的对象上授权 |
|
USER_TRIGGRS |
用户触发器的说明 |
|
USER_TRIGGRS_COLS |
用户所持有的或在用户表上的触发器中的列的用法 |
|
USER_TS_QUOTAS |
用户在表空间上的份额 |
|
USER_USERS |
关于当前用户的信息 |
|
USER_VIEWS |
用户持有的视图的文本 |
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