11g中统计信息自动收集任务的名称是auto optimizer stats collection。11g中自动任务默认的执行时间窗口为：
周一到周五是晚上10点开始到2点结束
周末是早上六点，持续20个小时。
1、查看自动收集任务及状态
select client_name,status from Dba_Autotask_Client where client_name='auto optimizer stats collection';
2、停止自动收集任务
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
但是此时再查询DBA_ATUOTASK_TASK视图时，显示该任务状态还是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给出的解释是在现在的版本中（11.1 to 11.2）一个client对应一个task，但是在将来的版本中会出现多个client会对应一个task，所以一个client被disabled了，不会改变task的状态。[ID 858852.1]
3、启动自动收集任务
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、查看自动收集任务历史执行状态
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
通过时间窗口名称可以看出是周几执行的，在时间窗口内创建了几次job，执行了几次job，当然可以加上window_start_time来查看具体执行的日期。
5、查看自动收集任务执行时间窗口
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
我将系统日期改为11月26日22点以后，MONDAY_WINDOW执行时间窗口自动激活。
6、查询自动收集任务正在执行的JOB
select client_name, JOB_SCHEDULER_STATUS from DBA_AUTOTASK_CLIENT_JOB where client_name='auto optimizer stats collection';
这个查询没有结果也很正常，只有job正在运行时，该查询才有结果。
7、与时间窗口相关的视图
查询自动收集任务所属时间窗口组
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$AT_WGRP_OS
查询自动收集任务所属时间窗口组详细信息
SQL> select * from dba_scheduler_window_groups where window_group_name='ORA$AT_WGRP_OS';WINDOW_GROUP_NA ENABL NUMBER_OF_WINDOWS NEXT_START_DATE COMMENTS --------------- ----- ----------------- ----------------------------------- --------------------------------------------- ORA$AT_WGRP_OS TRUE 7 26-NOV-12 10.00.00.000000 PM PRC auto optimizer stats collection
查看自动收集任务所属时间窗口组包含的子时间窗口
SQL> select * from dba_scheduler_wingroup_members where window_group_name='ORA$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$AT_WGRP_OS SUNDAY_WINDOW
查看子时间窗口信息
SQL> select a.window_name,a.next_start_date,a.active from dba_scheduler_windows a 2 inner join dba_scheduler_wingroup_members b on a.window_name = b.window_name 3 where b.window_group_name='ORA$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
通过这个查询可以看出DBA_AUTOTASK_WINDOW_CLIENTS视图的信息其实和上面的结果一样。
总结一下统计信息自动收集任务运行的步骤：
首先是dba_autotask_task-->dba_autotask_client建立自动执行任务
再根据时间窗口及资源组建立自动执行作业
dba_autotask_client-->dba_scheduler_window_groups-->dba_scheduler_windows
-->dba_scheduler_jobs
dba_autotask_client-->dba_scheduler_job_classes
－－－查看哪些表的统计信息是旧的
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:
$sqlplus / as sysdba
declare
mystaleobjs dbms_stats.objecttab;
begin
-- check whether there is any stale objects
dbms_stats.gather_schema_stats(ownname=>'TBCS',
options=>'LIST STALE',
objlist=>mystaleobjs);
for i in 1 .. mystaleobjs.count loop
dbms_output.put_line(mystaleobjs(i).objname);
end loop;
end;
/
declare
mystaleobjs dbms_stats.objecttab;
begin
-- check whether there is any stale objects
dbms_stats.gather_schema_stats(ownname=>'TBCS',
options=>'LIST EMPTY',
objlist=>mystaleobjs);
for i in 1 .. mystaleobjs.count loop
dbms_output.put_line(mystaleobjs(i).objname);
end loop;
end;
/
2. Please implement the following and provide relevant trace:
idle>exec DBMS_STATS.SET_GLOBAL_PREFS('trace', 4+8+16+64+128+512+2048);
PL/SQL procedure successfully completed.
idle>execute DBMS_STATS.FLUSH_DATABASE_MONITORING_INFO;
PL/SQL procedure successfully completed.
idle>exec DBMS_AUTO_TASK_IMMEDIATE.GATHER_OPTIMIZER_STATS;
PL/SQL procedure successfully completed.
To disable trace, you can :
idle>exec DBMS_STATS.SET_GLOBAL_PREFS('trace', 0);
-----如果考虑表大考虑调整收集到的百分比
begin
DBMS_STATS.SET_TABLE_PREFS (
ownname => 'TBCS',
tabname => 'RECEPTION',
pname => 'ESTIMATE_PERCENT',
pvalue => '1'); ------------- you
can adjust the percent to a smaller value(0.01 or 0.1 etc)
end;
/
---手动调用自动维护窗口的JOB
|
SQL> execute DBMS_STATS.FLUSH_DATABASE_MONITORING_INFO;
SQL> exec DBMS_AUTO_TASK_IMMEDIATE.GATHER_OPTIMIZER_STATS; This will prompt the Automated Maintenance Tasks subsystem into starting a job that will gather optimizer statistics, unless such a job is already running (for example if a maintenance window is currently open). If an immediate job is created it will be named ORA$_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. |
---查看历史的维护窗口
select * from DBA_AUTOTASK_JOB_HISTORY WHERE client_name ='auto optimizer stats collection' order by window_start_time desc;
---批量检查
set lines 500
set long 9999
set pages 999
set serveroutput on size 1000000
set feedback off
SET MARKUP HTML ON SPOOL ON HEAD "<TITLE>SQL*Plus Report</title><STYLE TYPE='TEXT/CSS'><!--BODY {background: ffffc6} --></STYLE>"
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
相关视图：
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
自定义自动收集任务时间窗口：
How to use an own Maintenance Window for the Statistics Collection in 11g [ID 1300313.1]
MOS相关文档： FAQ: Automatic Statistics Collection [ID 1233203.1]
How to Gather Optimizer Statistics on 11g ( Doc ID 749227.1 )
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