1.查看隱藏參數
腳本1:
SELECT x.ksppinm NAME, y.ksppstvl VALUE, x.ksppdesc describ
FROM SYS.x$ksppi x, SYS.x$ksppcv y
WHERE x.inst_id = USERENV ('Instance')
AND y.inst_id = USERENV ('Instance')
AND x.indx = y.indx
AND x.ksppinm LIKE '%&par%'腳本2:
select
x.ksppinm name,
y.ksppstvl value,
y.ksppstdf isdefault,
decode(bitand(y.ksppstvf,7),1,'MODIFIED',4,'SYSTEM_MOD','FALSE') ismod,
decode(bitand(y.ksppstvf,2),2,'TRUE','FALSE') isadj
from
sys.x$ksppi x,
sys.x$ksppcv y
where
x.inst_id = userenv('Instance') and
y.inst_id = userenv('Instance') and
x.indx = y.indx and
x.ksppinm like '%_&par%'
order by
translate(x.ksppinm,'_','') 2.Oracle通過一個內部參數_small_table_threshold來定義大表和小表的界限.缺省情況下該參數等于2%的數量,如果表的buffer大小小于這個參數的定義,則oracle認為它是小表,反之為大表.
select (db_cache_size/塊size)*0.02 from dual
posted on 2011-06-11 20:44
xrzp 閱讀(302)
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