Oracle11g 統計資訊-----統計資訊自動收集任務

531968912發表於2016-09-05
Oracle

11g中統計資訊自動收集任務的名稱是auto optimizer stats collection。11g中自動任務預設的執行時間視窗為：

    週一到週五是晚上10點開始到2點結束
    週末是早上六點，持續20個小時。
1、檢視自動收集任務及狀態 

select client_name,status from Dba_Autotask_Client where client_name='auto optimizer stats collection';

2、停止自動收集任務 

SQL> BEGIN
  2      DBMS_AUTO_TASK_ADMIN.DISABLE(
  3                     client_name => 'auto optimizer stats collection',
  4                     operation => NULL, window_name => NULL);
  5  END;
  6  /
 
PL/SQL procedure successfully completed.
SQL> select client_name,status from Dba_Autotask_Client where client_name='auto optimizer stats collection';
CLIENT_NAME                                                      STATUS
---------------------------------------------------------------- --------
auto optimizer stats collection                                  DISABLED

但是此時再查詢DBA_ATUOTASK_TASK檢視時，顯示該任務狀態還是ENABLED 

SQL> select client_name,status from dba_autotask_task where client_name='auto optimizer stats collection';
CLIENT_NAME                                                      STATUS
---------------------------------------------------------------- --------
auto optimizer stats collection                                  ENABLED

Oracle給出的解釋是在現在的版本中（11.1 to 11.2）一個client對應一個task，但是在將來的版本中會出現多個client會對應一個task，所以一個client被disabled了，不會改變task的狀態。[ID 858852.1]
3、啟動自動收集任務 

SQL> BEGIN
  2      DBMS_AUTO_TASK_ADMIN.ENABLE(
  3                     client_name => 'auto optimizer stats collection',
  4                     operation => NULL, window_name => NULL);
  5  END;
  6  /
PL/SQL procedure successfully completed.
SQL> select client_name,status from Dba_Autotask_Client where client_name='auto optimizer stats collection';
CLIENT_NAME                                                      STATUS
---------------------------------------------------------------- --------
auto optimizer stats collection                                  ENABLED

4、檢視自動收集任務歷史執行狀態 

 SQL> SELECT client_name, window_name, jobs_created, jobs_started, jobs_completed
  2   FROM dba_autotask_client_history
  3   WHERE client_name like '%stats%';
CLIENT_NAME                              WINDOW_NAME                    JOBS_CREATED JOBS_STARTED JOBS_COMPLETED
---------------------------------------- ------------------------------ ------------ ------------ --------------
auto optimizer stats collection          SATURDAY_WINDOW                           5            5              5
auto optimizer stats collection          SUNDAY_WINDOW                             6            6              6

通過時間視窗名稱可以看出是周幾執行的，在時間視窗內建立了幾次job，執行了幾次job，當然可以加上window_start_time來檢視具體執行的日期。
5、檢視自動收集任務執行時間視窗 


		

			SQL> select WINDOW_NAME, WINDOW_NEXT_TIME , WINDOW_ACTIVE,OPTIMIZER_STATS from DBA_AUTOTASK_WINDOW_CLIENTS order by WINDOW_NEXT_TIME ;
		


		

			WINDOW_NAME                    WINDOW_NEXT_TIME                                WINDO OPTIMIZE
------------------------------ ----------------------------------------------- ----- --------
MONDAY_WINDOW                  26-NOV-12 10.00.00.000000 PM PRC                TRUE  ENABLED
TUESDAY_WINDOW                 27-NOV-12 10.00.00.000000 PM PRC                FALSE ENABLED
WEDNESDAY_WINDOW               28-NOV-12 10.00.00.000000 PM PRC                FALSE ENABLED
THURSDAY_WINDOW                29-NOV-12 10.00.00.000000 PM PRC                FALSE ENABLED
FRIDAY_WINDOW                  30-NOV-12 10.00.00.000000 PM PRC                FALSE ENABLED
SATURDAY_WINDOW                01-DEC-12 06.00.00.000000 AM PRC                FALSE ENABLED
SUNDAY_WINDOW                  02-DEC-12 06.00.00.000000 AM PRC                FALSE ENABLED

我將系統日期改為11月26日22點以後，MONDAY_WINDOW執行時間視窗自動啟用。
6、查詢自動收集任務正在執行的JOB 

select client_name, JOB_SCHEDULER_STATUS from DBA_AUTOTASK_CLIENT_JOB where client_name='auto optimizer stats collection';

這個查詢沒有結果也很正常，只有job正在執行時，該查詢才有結果。
7、與時間視窗相關的檢視
查詢自動收集任務所屬時間視窗組 

SQL> select client_name,window_group from dba_autotask_client where client_name='auto optimizer stats collection';
CLIENT_NAME                              WINDOW_GROUP
---------------------------------------- ---------------------------------------------------
auto optimizer stats collection          ORA$AT_WGRP_OS

查詢自動收集任務所屬時間視窗組詳細資訊 

SQL> select * from dba_scheduler_window_groups where window_group_name='ORA$AT_WGRP_OS';
WINDOW_GROUP_NA ENABL NUMBER_OF_WINDOWS NEXT_START_DATE                     COMMENTS
--------------- ----- ----------------- ----------------------------------- ---------------------------------------------
ORA$AT_WGRP_OS  TRUE                  7 26-NOV-12 10.00.00.000000 PM PRC    auto optimizer stats collection

檢視自動收集任務所屬時間視窗組包含的子時間視窗 

SQL> select * from dba_scheduler_wingroup_members where window_group_name='ORA$AT_WGRP_OS';
WINDOW_GROUP_NA WINDOW_NAME
--------------- ------------------------------
ORA$AT_WGRP_OS  MONDAY_WINDOW
ORA$AT_WGRP_OS  TUESDAY_WINDOW
ORA$AT_WGRP_OS  WEDNESDAY_WINDOW
ORA$AT_WGRP_OS  THURSDAY_WINDOW
ORA$AT_WGRP_OS  FRIDAY_WINDOW
ORA$AT_WGRP_OS  SATURDAY_WINDOW ORA$AT_WGRP_OS  SUNDAY_WINDOW

檢視子時間視窗資訊 

SQL> select a.window_name,a.next_start_date,a.active from dba_scheduler_windows a
  2  inner join dba_scheduler_wingroup_members b on a.window_name = b.window_name
  3  where b.window_group_name='ORA$AT_WGRP_OS';
WINDOW_NAME                    NEXT_START_DATE                     ACTIV
------------------------------ ----------------------------------- -----
MONDAY_WINDOW                  26-NOV-12 10.00.00.000000 PM PRC    TRUE
TUESDAY_WINDOW                 27-NOV-12 10.00.00.000000 PM PRC    FALSE
WEDNESDAY_WINDOW               28-NOV-12 10.00.00.000000 PM PRC    FALSE
THURSDAY_WINDOW                29-NOV-12 10.00.00.000000 PM PRC    FALSE
FRIDAY_WINDOW                  30-NOV-12 10.00.00.000000 PM PRC    FALSE
SATURDAY_WINDOW                01-DEC-12 06.00.00.000000 AM PRC    FALSE
SUNDAY_WINDOW                  02-DEC-12 06.00.00.000000 AM PRC    FALSE

通過這個查詢可以看出DBA_AUTOTASK_WINDOW_CLIENTS檢視的資訊其實和上面的結果一樣。

總結一下統計資訊自動收集任務執行的步驟：
首先是dba_autotask_task--&gtdba_autotask_client建立自動執行任務
再根據時間視窗及資源組建立自動執行作業
dba_autotask_client--&gtdba_scheduler_window_groups--&gtdba_scheduler_windows
                                                                                                                                    --&gtdba_scheduler_jobs
dba_autotask_client--&gtdba_scheduler_job_classes

－－－檢視哪些表的統計資訊是舊的
Please create a test table in schema TBCS:

create table mytest(id number, name varchar2(100));

insert into mytest
select rownum,dbms_random.string('a',100)
from dual
connect by level <= 10000;

commit;

1. Pleas update SR with the following output:

$sqlplus / as sysdba

declare
mystaleobjs dbms_stats.objecttab;
begin
-- check whether there is any stale objects
dbms_stats.gather_schema_stats(ownname=>'TBCS',
options=>'LIST STALE',
objlist=>mystaleobjs);
for i in 1 .. mystaleobjs.count loop
dbms_output.put_line(mystaleobjs(i).objname);
end loop;
end;
/

declare
mystaleobjs dbms_stats.objecttab;
begin
-- check whether there is any stale objects
dbms_stats.gather_schema_stats(ownname=>'TBCS',
options=>'LIST EMPTY',
objlist=>mystaleobjs);
for i in 1 .. mystaleobjs.count loop
dbms_output.put_line(mystaleobjs(i).objname);
end loop;
end;
/

2. Please implement the following and provide relevant trace:

idle>exec DBMS_STATS.SET_GLOBAL_PREFS('trace', 4+8+16+64+128+512+2048);

PL/SQL procedure successfully completed.

idle>execute DBMS_STATS.FLUSH_DATABASE_MONITORING_INFO;

PL/SQL procedure successfully completed.

idle>exec DBMS_AUTO_TASK_IMMEDIATE.GATHER_OPTIMIZER_STATS;

PL/SQL procedure successfully completed.

To disable trace, you can :

idle>exec DBMS_STATS.SET_GLOBAL_PREFS('trace', 0); 


-----如果考慮表大考慮調整收集到的百分比
begin
DBMS_STATS.SET_TABLE_PREFS (
ownname => 'TBCS',
tabname => 'RECEPTION',
pname => 'ESTIMATE_PERCENT',
pvalue => '1'); ------------- you can adjust the percent to a smaller value(0.01 or 0.1 etc)
end;
/ 

---手動呼叫自動維護視窗的JOB
SQL> execute DBMS_STATS.FLUSH_DATABASE_MONITORING_INFO;

SQL> exec DBMS_AUTO_TASK_IMMEDIATE.GATHER_OPTIMIZER_STATS;

This will prompt the Automated Maintenance Tasks subsystem into starting a job that will gather optimizer statistics, unless such a job is already running (for example if a maintenance window is currently open). If an immediate job is created it will be named ORA$_AT_OS_MANUAL_nnnnnn (nnnnn is one or more decimal digits). Unlike regular Automated Maintenance jobs, the "MANUAL" job is not tied to a specific maintenance window. 


---檢視歷史的維護視窗
select * from DBA_AUTOTASK_JOB_HISTORY WHERE client_name ='auto optimizer stats collection' order by window_start_time desc;  


---批量檢查
set lines 500
set long 9999
set pages 999
set serveroutput on size 1000000
set feedback off
SET MARKUP HTML ON SPOOL ON HEAD "SQL*Plus Report"
spool query_result.html
set echo off
alter session set nls_date_format='yyyy/mm/dd hh24:mi:ss';
alter session set nls_timestamp_tz_format='yyyy/mm/dd hh24:mi:ss tzh:tzm';
select to_char(systimestamp,'yyyy/mm/dd hh24:mi:ss tzh:tzm') from dual;
select * from dba_autotask_client;
select * from DBA_SCHEDULER_WINGROUP_MEMBERS order by window_group_name,window_name;
select * from DBA_AUTOTASK_WINDOW_CLIENTS;
select * from DBA_AUTOTASK_SCHEDULE;
select * from DBA_AUTOTASK_WINDOW_HISTORY order by window_start_time desc;
select * from DBA_AUTOTASK_JOB_HISTORY WHERE client_name ='auto optimizer stats collection' order by window_start_time desc;
spool off
SET MARKUP HTML OFF 



相關檢視：
dba_autotask_task
dba_autotask_client
dba_autotask_client_job
dba_autotask_window_clients
dba_autotask_client_history

dba_scheduler_jobs
dba_scheduler_job_classes
dba_scheduler_window_groups
dba_scheduler_windows
dba_scheduler_wingroup_members

自定義自動收集任務時間視窗：
How to use an own Maintenance Window for the Statistics Collection in 11g [ID 1300313.1]

MOS相關文件： FAQ: Automatic Statistics Collection [ID 1233203.1]
How to Gather Optimizer Statistics on 11g ( Doc ID 749227.1 ) 

來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/29446986/viewspace-1692544/，如需轉載，請註明出處，否則將追究法律責任。

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