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oracle等待事件相关查询

2014-11-11 19:14 387 查看
--------------------------查询数据库等待时间和实际执行时间的相对百分比---------------------

select *

  from v$sysmetric a

 where a.METRIC_NAME in

       ('Database CPU Time Ratio', 'Database Wait Time Ratio')

   and a.INTSIZE_CSEC = (select max(intsize_csec) from v$sysmetric);

-------------------------------------查询数据库中过去30分钟引起最多等待的sql语句----------------

select ash.USER_ID,

       u.username,

       sum(ash.WAIT_TIME) ttl_wait_time,

       s.SQL_TEXT

  from v$active_session_history ash, v$sqlarea s, dba_users u

 where ash.SAMPLE_TIME between sysdate - 60 / 2880 and sysdate

   and ash.SQL_ID = s.SQL_ID

   and ash.USER_ID = u.user_id

 group by ash.USER_ID, s.SQL_TEXT, u.username

 order by ttl_wait_time desc

-----------------------------------------查询数据库中的等待事件----------------------

select event, count(*)

  from v$session_wait

 group by event

 order by count(*) desc

---------------------------------------查询数据库过去15分钟最重要的等待事件---------------

select ash.EVENT, sum(ash.WAIT_TIME + ash.TIME_WAITED) total_wait_time

  from v$active_session_history ash

 where ash.SAMPLE_TIME between sysdate - 30 / 2880 and sysdate

 group by event

 order by total_wait_time desc

----------------------------------------在过去15分钟哪些用户经历了等待---------------------

select s.SID,

       s.USERNAME,

       sum(ash.WAIT_TIME + ash.TIME_WAITED) total_wait_time

  from v$active_session_history ash, v$session s

 where ash.SAMPLE_TIME between sysdate - 30 / 2880 and sysdate

   and ash.SESSION_ID = s.SID

 group by s.SID, s.USERNAME

 order by total_wait_time desc;

-------------------------------------查询等待时间最长的对象---------------------------------------

select a.CURRENT_OBJ#,

       d.object_name,

       d.object_type,

       a.EVENT,

       sum(a.WAIT_TIME + a.TIME_WAITED) total_wait_time

  from v$active_session_history a, dba_objects d

 where a.SAMPLE_TIME between sysdate - 30 / 2880 and sysdate

   and a.CURRENT_OBJ# = d.object_id

 group by a.CURRENT_OBJ#, d.object_name, d.object_type, a.EVENT

 order by total_wait_time desc;

--------------------------------------------查询过去15分钟等待时间最长的sql语句---------------------------

select a.USER_ID,

       u.username,

       s.SQL_TEXT,

       sum(a.WAIT_TIME + a.TIME_WAITED) total_wait_time

  from v$active_session_history a, v$sqlarea s, dba_users u

 where a.SAMPLE_TIME between sysdate - 30 / 2880 and sysdate

   and a.SQL_ID = s.SQL_ID

   and a.USER_ID = u.user_id

 group by a.USER_ID, s.SQL_TEXT, u.username

 order by total_wait_time desc;

------------------------------------------那些SQL消耗更多的IO--------------------------------------

select *

  from (select s.PARSING_SCHEMA_NAME,

               s.DIRECT_WRITES,

               substr(s.SQL_TEXT, 1, 500),

               s.DISK_READS

          from v$sql s

         order by s.DISK_READS desc)

 where rownum < 20

---------------------------------------查看哪些会话正在等待IO资源-------------------------------------

SELECT username, program, machine, sql_id

  FROM V$SESSION

 WHERE EVENT LIKE 'db file%read';

----------------------------------查看正在等待IO资源的对象-----------------------------------

SELECT d.object_name, d.object_type, d.owner

  FROM V$SESSION s, dba_objects d

 WHERE EVENT LIKE 'db file%read'

   and s.ROW_WAIT_OBJ# = d.object_id

---------------------------查看redo日志切换频率---------------------------------------------

Select round(FIRST_TIME, 'DD'), THREAD#, Count(SEQUENCE#)

  From v$log_history

 Group By round(FIRST_TIME, 'DD'), THREAD#

 Order By 1, 2

SELECT  trunc(first_time) "Date",

        to_char(first_time, 'Dy') "Day",

        count(1) "Total",

        SUM(decode(to_char(first_time, 'hh24'),'00',1,0)) "h0",

        SUM(decode(to_char(first_time, 'hh24'),'01',1,0)) "h1",

        SUM(decode(to_char(first_time, 'hh24'),'02',1,0)) "h2",

        SUM(decode(to_char(first_time, 'hh24'),'03',1,0)) "h3",

        SUM(decode(to_char(first_time, 'hh24'),'04',1,0)) "h4",

        SUM(decode(to_char(first_time, 'hh24'),'05',1,0)) "h5",

        SUM(decode(to_char(first_time, 'hh24'),'06',1,0)) "h6",

        SUM(decode(to_char(first_time, 'hh24'),'07',1,0)) "h7",

        SUM(decode(to_char(first_time, 'hh24'),'08',1,0)) "h8",

        SUM(decode(to_char(first_time, 'hh24'),'09',1,0)) "h9",

        SUM(decode(to_char(first_time, 'hh24'),'10',1,0)) "h10",

        SUM(decode(to_char(first_time, 'hh24'),'11',1,0)) "h11",

        SUM(decode(to_char(first_time, 'hh24'),'12',1,0)) "h12",

        SUM(decode(to_char(first_time, 'hh24'),'13',1,0)) "h13",

        SUM(decode(to_char(first_time, 'hh24'),'14',1,0)) "h14",

        SUM(decode(to_char(first_time, 'hh24'),'15',1,0)) "h15",

        SUM(decode(to_char(first_time, 'hh24'),'16',1,0)) "h16",

        SUM(decode(to_char(first_time, 'hh24'),'17',1,0)) "h17",

        SUM(decode(to_char(first_time, 'hh24'),'18',1,0)) "h18",

        SUM(decode(to_char(first_time, 'hh24'),'19',1,0)) "h19",

        SUM(decode(to_char(first_time, 'hh24'),'20',1,0)) "h20",

        SUM(decode(to_char(first_time, 'hh24'),'21',1,0)) "h21",

        SUM(decode(to_char(first_time, 'hh24'),'22',1,0)) "h22",

        SUM(decode(to_char(first_time, 'hh24'),'23',1,0)) "h23"

FROM    V$log_history

group by trunc(first_time), to_char(first_time, 'Dy')

Order by 1
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