GATHER_STATS_JOB
今天檢查alert日誌的時候發現以下報錯：
ORA-1652:unable to extend temp segment by 128 in tablespace TEMP
MonNov 25 22:57:07 2013
GATHER_STATS_JOB encountered errors. Check the trace file.
MonNov 25 22:57:07 2013
Errorsin file /u01/oracle/admin/epqdb/bdump/epqdb2_ora_26041.trc:
ORA-01652: unable to extend temp segment by 128 intablespace TEMP
很明顯是temp表空間不夠。
但讓我關注的不是該ORA-1652錯誤，而是GATHER_STATS_JOB，以前都沒有了解過，這裏就做下知識補充。
GATHER_STATS_JOB是10g開始引入的自動統計數據收集功能的重要組成部分，但是這個定時任務帶來的問題也是較多的，應當根據應用的具體情況進行定製。
--通過DBA_SCHEDULER_JOBS可以查詢JOB的執行情況：
SQL> col job_name for a20
SQL> col owner for a5
SQL> col last_start_date for a36
SQL> col last_run_duration for a30
SQL> col state for a10
SQL> SELECTowner,job_name,state,last_start_date,last_run_duration,failure_count
FROM dba_scheduler_jobs WHERE job_name ='GATHER_STATS_JOB';
OWNERJOB_NAME STATE LAST_START_DATE LAST_RUN_DURATION FAILURE_COUNT
------------------------- ---------- ------------------------------------------------------------------ -------------
SYS GATHER_STATS_JOB SCHEDULED 25-NOV-13 10.00.02.884222 PM +08:00 +000000000 00:04:45.756662 0
--查看GATHER_STATS_JOB運行的具體過程：
SQL> select PROGRAM_ACTION from dba_scheduler_programs where PROGRAM_NAME ='GATHER_STATS_PROG';
PROGRAM_ACTION
---------------------------------------------------------------------------------------------------------------------------------
dbms_stats.gather_database_stats_job_proc
--查看GATHER_STATS_JOB的運行日誌：
SQL> SELECT log_id, job_name, status,
2 TO_CHAR (log_date, 'DD-MON-YYYYHH24:MI') log_date
3 FROM dba_scheduler_job_run_details
4 WHERE job_name = 'GATHER_STATS_JOB' order by 1 desc;
LOG_IDJOB_NAME STATUS LOG_DATE
------------------------------ ------------------------------ -----------------------
26286GATHER_STATS_JOB SUCCEEDED 25-NOV-2013 22:04
26254GATHER_STATS_JOB SUCCEEDED 23-NOV-2013 06:14
26246GATHER_STATS_JOB SUCCEEDED 22-NOV-2013 22:03
26196GATHER_STATS_JOB SUCCEEDED 21-NOV-2013 22:02
26189GATHER_STATS_JOB SUCCEEDED 20-NOV-2013 22:02
26165GATHER_STATS_JOB SUCCEEDED 19-NOV-2013 22:02
26145GATHER_STATS_JOB SUCCEEDED 18-NOV-2013 22:02
26114GATHER_STATS_JOB SUCCEEDED 16-NOV-2013 06:01
26108GATHER_STATS_JOB SUCCEEDED 15-NOV-2013 22:02
26085GATHER_STATS_JOB SUCCEEDED 14-NOV-2013 22:02
26045GATHER_STATS_JOB SUCCEEDED 12-NOV-2013 22:01
……
參考eygle的blog：http://www.eygle.com/archives/2009/09/gather_stats_job.html