如何查找隐藏参数(x$ksppi and x$ksppsv)

select name  
,value  
,decode(isdefault, 'TRUE','Y','N') as "Default"  
,decode(ISEM,'TRUE','Y','N') as SesMod  
,decode(ISYM,'IMMEDIATE', 'I',  
'DEFERRED', 'D',  
'FALSE', 'N') as SysMod  
,decode(IMOD,'MODIFIED','U',  
'SYS_MODIFIED','S','N') as Modified  
,decode(IADJ,'TRUE','Y','N') as Adjusted  
,description  
from ( --GV$SYSTEM_PARAMETER  
select x.inst_id as instance  
,x.indx+1  
,ksppinm as name  
,ksppity  
,ksppstvl as value  
,ksppstdf as isdefault  
,decode(bitand(ksppiflg/256,1),1,'TRUE','FALSE') as ISEM  
,decode(bitand(ksppiflg/65536,3),  
1,'IMMEDIATE',2,'DEFERRED','FALSE') as ISYM  
,decode(bitand(ksppstvf,7),1,'MODIFIED','FALSE') as IMOD  
,decode(bitand(ksppstvf,2),2,'TRUE','FALSE') as IADJ  
,ksppdesc as description  
from x$ksppi x  
,x$ksppsv y  
where x.indx = y.indx  
and substr(ksppinm,1,1) = '_'  
and x.inst_id = USERENV('Instance')  
)  
order by name