最简单的例子就是Oracle的数据字典视图，比如USER_DB_LINKS。

对于USER_DB_LINKS视图的定义的固定的，但是每个用户访问得到的结果是不同的，就是由于USER_DB_LINKS视图中使用了变量：

SQL> select text     
  2  from dba_views
  3  where view_name = 'USER_DB_LINKS';

TEXT
--------------------------------------------------------------------------------
select l.name, l.userid, l.password, l.host, l.ctime
from sys.link$ l
where l.owner# = userenv('SCHEMAID')

由于使用了USERENV函数获取SCHEMAID信息，使得不同的用户登陆获得的方案ID不同，从而使得不同的用户访问USER_DB_LINKS视图获得的结果不同。

这里可以利用USER模仿一个类似的例子：

SQL> create table t_user            
  2  as select *
  3  from dba_users;

Table created.

SQL> create view my_user
  2  as select *
  3  from t_user
  4  where username = user;

View created.

SQL> grant select on my_user to public;

Grant succeeded.

SQL> show user
USER is "TEST"
SQL> select username, account_status
  2  from my_user;

USERNAME                       ACCOUNT_STATUS
------------------------------ --------------------------------
TEST                           OPEN

SQL> conn / as sysdba
Connected.
SQL> show user
USER is "SYS"
SQL> select username, account_status
  2  from test.my_user;

USERNAME                       ACCOUNT_STATUS
------------------------------ --------------------------------
SYS                            OPEN

SQL> conn u1/u1
Connected.
SQL> select username, account_status
  2  from test.my_user;

USERNAME                       ACCOUNT_STATUS
------------------------------ --------------------------------
U1                             OPEN

除了USER变量之外，还可以使用类似SYSDATE之类的变量来重建动态视图：

SQL> create table t_date
  2  (id number,
  3  time date);

Table created.

SQL> insert into t_date
  2  select rownum, sysdate + rownum/86400 
  3  from dba_objects;

70858 rows created.

SQL> commit;

Commit complete.

SQL> create view v_date
  2  as select *     
  3  from t_date
  4  where time = sysdate;

View created.

SQL> alter session set nls_date_format = 'yyyy-mm-dd hh24:mi:ss';

Session altered.

SQL> select * from v_date;

        ID TIME
---------- -------------------
        43 2009-08-17 16:40:53

SQL> select * from v_date;

        ID TIME
---------- -------------------
        48 2009-08-17 16:40:58

SQL> select * from v_date;

        ID TIME
---------- -------------------
        55 2009-08-17 16:41:05

除了这些变量外，还可以利用DBMS_RANDOM包来构造动态的结果：

SQL> create table t_id (id number);

Table created.

SQL> insert into t_id                       
  2  select rownum               
  3  from dba_objects
  4  where rownum <= 10000;

10000 rows created.

SQL> commit;

Commit complete.

SQL> create view v_random as
  2  select * from t_id
  3  where id =
  4  (select round(dbms_random.value(1, 10000)) from dual);

View created.

SQL> select * from v_random;

        ID
----------
      8258

SQL> select * from v_random;

        ID
----------
      3827

SQL> select * from v_random;

        ID
----------
      7970

SQL> select * from v_random;

        ID
----------
      6750

合理的利用这些变量创建视图，可以建立很多有趣的对象。