Oracle 隐含参数的查询

普通的参数通过pfile或者spfile，甚至show parameter 都可以看到，但是隐含参数就要靠下面的语句查出来了：

set linesize 160;
col "_add_skiprules" format a30 ; 
col "Instance Value" format a30;  
col "Session Value" format a30; 
col Parameter format a50;

SELECT
a.ksppinm "Parameter",
b.ksppstvl "Session Value",
c.ksppstvl "Instance Value"
FROM
x$ksppi a,
x$ksppcv b,
x$ksppsv c
WHERE
a.indx = b.indx
AND
a.indx = c.indx
AND
a.ksppinm LIKE '/_%' escape '/'

还有下面这个语句：

set linesize 160;
col name format a50; 
col value format a30;  
col description format a40;
select a.ksppinm name,b.ksppstvl value,a.ksppdesc description
from x$ksppi a,x$ksppcv b
where a.indx = b.indx