禁止游标共享

发现了一个隐含参数_disable_cursor_sharing  可以用来禁止游标的共享，不过这个隐含参数没有什么意义，
违背了ORACLE尽量游标共享的理念。

下面看一下这个参数的作用：

SQL> show parameter disable_cursor_sharing  


NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
_disable_cursor_sharing              boolean     TRUE
SQL> variable id number
SQL> exec :id:=1;


PL/SQL procedure successfully completed.


SQL> select * from t where id=:id;


no rows selected


SQL> select sql_text,executions from v$sql where sql_text='select * from t where id=:id';


SQL_TEXT                       EXECUTIONS
------------------------------ ----------
select * from t where id=:id            1


SQL> exec :id:=2;


PL/SQL procedure successfully completed.


SQL> select * from t where id=:id;


no rows selected


SQL> select sql_text,executions from v$sql where sql_text='select * from t where id=:id';


SQL_TEXT                       EXECUTIONS
------------------------------ ----------
select * from t where id=:id            1
select * from t where id=:id            1

仅供参考。