====== 오라클 데이타베이스 관리를 위한 쿼리 모음 ======

  - 10분이내에 수행된 쿼리중 세션에 남아있는 쿼리 <code sql>
select sql_text
  from v$sqltext a, v$session b
 where a.hash_value = b.sql_hash_value
   and logon_time <= to_date(to_char(sysdate,'yyyymmddhh24mi')-10,'yyyymmddhh24mi');
</code>
  - Buffer Cache Hit Ratio <code sql>
SELECT ROUND(((1-(SUM(DECODE(name, 'physical reads', value,0))/
(SUM(DECODE(name, 'db block gets', value,0))+
(SUM(DECODE(name, 'consistent gets', value, 0))))))*100),2) || '%' "Buffer Cache Hit Ratio"
FROM V$SYSSTAT;
</code>
  - Library Cache Hit Ratio <code sql>
SELECT (1-SUM (reloads)/SUM(pins))*100 "Library Cache Hit Ratio"
From V$LIBRARYCACHE;
</code>
  - Data Dictionary Cache Hit Ratio <code sql>
SELECT (1-SUM(getmisses)/SUM(gets))*100 "Data Dictionary Hit Ratio"
FROM V$ROWCACHE;
</code>
  - 테이블 스페이스 사용량 <code sql>
SELECT a.tablespace_name ,
       a.total "Total(Mb)" ,
       a.total - b.free "Used(Mb)" ,
       NVL( b.free , 0 ) "Free(Mb)" ,
       ROUND(( a.total - NVL( b.free , 0 ) ) *100/total , 0 ) "Used(%)"
FROM   (
        SELECT tablespace_name ,
               ROUND(( SUM( bytes ) /1024/1024 ) , 0 ) AS total
        FROM   dba_data_files
        GROUP  BY tablespace_name
       ) a ,
       (
        SELECT tablespace_name ,
               ROUND(( SUM( bytes ) /1024/1024 ) , 0 ) AS free
        FROM   dba_free_space
        GROUP  BY tablespace_name
       ) b
WHERE  a.tablespace_name = b.tablespace_name( + )
ORDER  BY a.tablespace_name ;
</code>
  - 오라클서버의 메모리 <code sql>
select * from v$sgastat

select pool, sum(bytes) "SIZE"
from v$sgastat
where pool = 'shared pool'
group by pool
</code>
  - cpu를 많이 사용하는 쿼리문과 프로세스아이디,시리얼번호,머신 알아내기 <code sql>
select c.sql_text
,b.SID
, b.SERIAL#
,b.machine
,b.OSUSER
,b.logon_time --이 쿼리를 호출한 시간
from v$process a, v$session b, v$sqltext c
where a.addr = b.paddr
and b.sql_hash_value = c.hash_value
--and a.spid = '675958'
order by c.PIECE
</code>
  - cpu를 많이 사용하는 쿼리문과 프로세스아이디,시리얼번호,머신 알아내기2 <code sql>
select c.sql_text
from v$process a, v$session b, v$sqltext c
where a.addr = b.paddr
and b.sql_hash_value = c.hash_value
and a.spid = '171'
order by c.PIECE
</code> 
  - 프로세스 아이디를 이용하여 쿼리문 알아내기 <code sql>
select c.sql_text
,b.SID
, b.SERIAL#
,b.machine
,b.OSUSER
,b.logon_time --이 쿼리를 호출한 시간
from v$process a, v$session b, v$sqltext c
where a.addr = b.paddr
and b.sql_hash_value = c.hash_value
and a.spid = '1708032' --1912870/
order by c.PIECE
</code>
  - 세션 죽이기(SID,SERAIL#) <code sql>
ALTER SYSTEM KILL SESSION '8,4093'
</code>
  - 오라클 세션과 관련된 테이블 <code sql>
select count(*) from v$session where machine ='머신이름' and schemaname ='스키마이름'
</code>
  - 현재 커서 수 확인 <code sql>
SELECT sid, count(sid) cursor
FROM V$OPEN_CURSOR
WHERE user_name = 'ilips'
GROUP BY sid
ORDER BY cursor DESC

SELECT sql_text, count(sid) cnt
FROM v$OPEN_CURSOR
GROUP BY sql_text
ORDER BY cnt DESC

select * from v$session_wait

select sid, serial#, username, taddr, used_ublk, used_urec
from v$transaction t, v$session s
where t.addr = s.taddr;

select *  from sys.v_$open_cursor
</code>
  - V$LOCK 을 사용한 잠금 경합 모니터링 <code sql>
SELECT s.username, s.sid, s.serial#, s.logon_time,
    DECODE(l.type, 'TM', 'TABLE LOCK',
      'TX', 'ROW LOCK',
       NULL) "LOCK LEVEL",
    o.owner, o.object_name, o.object_type
FROM v$session s, v$lock l, dba_objects o
WHERE s.sid = l.sid
AND o.object_id = l.id1
AND s.username IS NOT NULL
</code>
  - 락이 걸린 세션 자세히 알아보기 <code sql>
select a.sid, a.serial#,a.username,a.process,b.object_name,
decode(c.lmode,2,'RS',3,'RX',4,'S',5,'SRX',8,'X','NO') "TABLE LOCK",
decode (a.command,2,'INSERT',3,'SELECT',6,'UPDATE',7,'DELETE',12,'DROP TABLE',26,'LOCK TABLE','UNknown') "SQL",
decode(a.lockwait, NULL,'NO wait','Wait') "STATUS"
from v$session a,dba_objects b, v$lock c
where a.sid=c.sid and b.object_id=c.id1
and c.type='TM'
</code>
  - 락이 걸린 세션 간단히 알아보기 <code sql>
select a.sid, a.serial#, b.type, c.object_name, a.program, a.lockwait,
       a.logon_time, a.process, a.osuser, a.terminal
from v$session a, v$lock b, dba_objects c
where a.sid = b.sid
  and b.id1 = c.object_id
  and b.type = 'TM';
select a.sid, a.serial#, a.username, a.process, b.object_name
from v$session a , dba_objects b, v$lock c
where a.sid=c.sid and b.object_id = c.id1
and c.type = 'TM'
</code>
  - 락이 걸린 세션을 찾아 내어 세션을 죽이려고 해도 죽지 않는 경우 \\ 아래 쿼리문으로 OS단의 PROCESS ID를 찾아내어 OS에서 죽인다. \\ <code sh> # kill -9 프로세스아이디 </code> \\ <code sql>
select substr(s.username,1,11) "ORACLE USER", p.pid "PROCESS ID",
s.sid "SESSION ID", s.serial#, osuser "OS USER",
p.spid "PROC SPID",s.process "SESS SPID", s.lockwait "LOCK WAIT"
from v$process p, v$session s, v$access a
where a.sid=s.sid and
p.addr=s.paddr and
s.username != 'SYS'
</code> \\ 위 쿼리문의 결과가 있다면 락이 걸린 세션이 있다는것이므로 아래의 쿼리문으로 세션을 죽인다. <code sql> 
ALTER SYSTEM KILL SESSION '11,39061'
</code>