今天在重构数据库时(将表空间中的表、索引转移到其它表空间)时,发现有两个奇怪的对象SYS_EXPORT_FULL_01、SYS_EXPORT_FULL_02搜索了一下,发现这个可能是EXPDP导出异常时遗留下的对象,但是搜到的资料不多,不能确认其具体用途以及该表是否删除。后来同事在metalink搜索到这篇文章。了解到这些表的相关详细信息。
如下所示,SYS_EXPORT_FULL_01、SYS_EXPORT_FULL_02是一个完整的数据库导出作业,状态是NOT RUNNING,意味着作业是暂时的停止,实际上作业失败了也是NOT RUNNING状态。
这表示以前(可能是很久以前)停止的作业,当然这些作业不可能重新启动,完全可以删除这些master表.
DROP TABLE ADMIN.SYS_EXPORT_FULL_01;
DROP TABLE ADMIN.SYS_EXPORT_FULL_02;
中的详细内容介绍如下所示:
The jobs used in this example:- Export job SCOTT.EXPDP_20051121 is a schema level export that is running- Export job SCOTT.SYS_EXPORT_TABLE_01 is an orphaned table level export job- Export job SCOTT.SYS_EXPORT_TABLE_02 is a table level export job that was stopped- Export job SYSTEM.SYS_EXPORT_FULL_01 is a full database export job that is temporary stopped
Step 1. Determine in SQL*Plus which Data Pump jobs exist in the database:
%sqlplus /nologCONNECT / as sysdba SET lines 200 COL owner_name FORMAT a10; COL job_name FORMAT a20 COL state FORMAT a12COL operation LIKE state COL job_mode LIKE state COL owner.object for a50-- locate Data Pump jobs: SELECT owner_name, job_name, rtrim(operation) "OPERATION", rtrim(job_mode) "JOB_MODE", state, attached_sessions FROM dba_datapump_jobs WHERE job_name NOT LIKE 'BIN$%' ORDER BY 1,2;OWNER_NAME JOB_NAME OPERATION JOB_MODE STATE ATTACHED---------- ------------------- --------- --------- ----------- --------SCOTT EXPDP_20051121 EXPORT SCHEMA EXECUTING 1SCOTT SYS_EXPORT_TABLE_01 EXPORT TABLE NOT RUNNING 0 SCOTT SYS_EXPORT_TABLE_02 EXPORT TABLE NOT RUNNING 0 SYSTEM SYS_EXPORT_FULL_01 EXPORT FULL NOT RUNNING 0
Step 2. Ensure that the listed jobs in dba_datapump_jobs are not export/import Data Pump jobs that are active: status should be 'NOT RUNNING'.Step 3. Check with the job owner that the job with status 'NOT RUNNING' in dba_datapump_jobs is not an export/import Data Pump job that has been temporary stopped, but is actually a job that failed. (E.g. the full database export job by SYSTEM is not a job that failed, but was deliberately paused with STOP_JOB).
Step 4. Determine in SQL*Plus the related master tables:
-- locate Data Pump master tables: SELECT o.status, o.object_id, o.object_type, o.owner||'.'||object_name "OWNER.OBJECT" FROM dba_objects o, dba_datapump_jobs j WHERE o.owner=j.owner_name AND o.object_name=j.job_name AND j.job_name NOT LIKE 'BIN$%' ORDER BY 4,2; STATUS OBJECT_ID OBJECT_TYPE OWNER.OBJECT ------- ---------- ------------ ------------------------- VALID 85283 TABLE SCOTT.EXPDP_20051121 VALID 85215 TABLE SCOTT.SYS_EXPORT_TABLE_02 VALID 85162 TABLE SYSTEM.SYS_EXPORT_FULL_01
Step 5. For jobs that were stopped in the past and won't be restarted anymore, delete the master table. E.g.:
DROP TABLE scott.sys_export_table_02;-- For systems with recycle bin additionally run:purge dba_recyclebin;
NOTE:In case the table name is mixed case, you can get errors on the drop, e.g.:
SQL> drop table SYSTEM.impdp_schema_STGMDM_10202014_0;drop table SYSTEM.impdp_schema_STGMDM_10202014_0 *ERROR at line 1:ORA-00942: table or view does not exist
Because the table has a mixed case, try using these statements with double quotes around the table name, for instance:
drop table SYSTEM."impdp_SCHEMA_STGMDM_04102015_1";drop table SYSTEM."impdp_schema_STGMDM_10202014_0";
Step 6. Re-run the query on dba_datapump_jobs and dba_objects (step 1 and 4). If there are still jobs listed in dba_datapump_jobs, and these jobs do not have a master table anymore, cleanup the job while connected as the job owner. E.g.:
CONNECT scott/tiger SET serveroutput on SET lines 100 DECLARE h1 NUMBER; BEGIN h1 := DBMS_DATAPUMP.ATTACH('SYS_EXPORT_TABLE_01','SCOTT'); DBMS_DATAPUMP.STOP_JOB (h1); END; /
Note that after the call to the STOP_JOB procedure, it may take some time for the job to be removed. Query the view user_datapump_jobs to check whether the job has been removed:
CONNECT scott/tiger SELECT * FROM user_datapump_jobs;
Step 7. Confirm that the job has been removed:
CONNECT / as sysdba SET lines 200 COL owner_name FORMAT a10; COL job_name FORMAT a20 COL state FORMAT a12 COL operation LIKE state COL job_mode LIKE state COL owner.object for a50-- locate Data Pump jobs: SELECT owner_name, job_name, rtrim(operation) "OPERATION", rtrim(job_mode) "JOB_MODE", state, attached_sessions FROM dba_datapump_jobs WHERE job_name NOT LIKE 'BIN$%' ORDER BY 1,2;OWNER_NAME JOB_NAME OPERATION JOB_MODE STATE ATTACHED ---------- ------------------- --------- --------- ----------- -------- SCOTT EXPDP_20051121 EXPORT SCHEMA EXECUTING 1 SYSTEM SYS_EXPORT_FULL_01 EXPORT FULL NOT RUNNING 0 -- locate Data Pump master tables: SELECT o.status, o.object_id, o.object_type, o.owner||'.'||object_name "OWNER.OBJECT" FROM dba_objects o, dba_datapump_jobs j WHERE o.owner=j.owner_name AND o.object_name=j.job_name AND j.job_name NOT LIKE 'BIN$%' ORDER BY 4,2; STATUS OBJECT_ID OBJECT_TYPE OWNER.OBJECT ------- ---------- ------------ ------------------------- VALID 85283 TABLE SCOTT.EXPDP_20051121 VALID 85162 TABLE SYSTEM.SYS_EXPORT_FULL_01
Remarks:1. Orphaned Data Pump jobs do not have an impact on new Data Pump jobs. The view dba_datapump_jobs is a view, based on gv$datapump_job, obj$, com$, and user$. The view shows the Data Pump jobs that are still running, or jobs for which the master table was kept in the database, or in case of an abnormal end of the Data Pump job (the orphaned job). If a new Data Pump job is started, a new entry will be created, which has no relation to the old Data Pump jobs.
2. When starting the new Data Pump job and using a system generated name, we check the names of existing Data Pump jobs in the dba_datapump_job in order to obtain a unique new system generated jobname. Naturally, there needs to be enough free space for the new master table to be created in the schema that started the new Data Pump job.
3. A Data Pump job is not the same as a job that is defined with DBMS_JOBS. Jobs created with DBMS_JOBS use there own processes. Data Pump jobs use a master process and worker process(es). In case a Data Pump still is temporary stopped (STOP_JOB while in interactive command mode), the Data Pump job still exists in the database (status: NOT RUNNING), while the master and worker process(es) are stopped and do not exist anymore. The client can attach to the job at a later time, and continue the job execution (START_JOB).
4. The possibility of corruption when the master table of an active Data Pump job is deleted, depends on the Data Pump job.4.a. If the job is an export job, corruption is unlikely as the drop of the master table will only cause the Data Pump master and worker processes to abort. This situation is similar to aborting an export of the original export client.4.b. If the job is an import job then the situation is different. When dropping the master table, the Data Pump worker and master processes will abort. This will probably lead to an incomplete import: e.g. not all table data was imported, and/or table was imported incomplete, and indexes, views, etc. are missing. This situation is similar to aborting an import of the original import client.
The drop of the master table itself, does not lead to any data dictionary corruption. If you keep the master table after the job completes (using the undocumented parameter: KEEP_MASTER=Y), then a drop of the master table afterwards, will not cause any corruption.
5. Instead of the status 'NOT RUNNING' the status of a failed job could also be 'DEFINING'. When trying to attach to such a job, this would fail with:
$ expdp system/manager attach=system.sys_export_schema_01Export: Release 11.2.0.4.0 - Production on Tue Jan 27 10:14:27 2015Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit ProductionWith the Partitioning, OLAP, Data Mining and Real Application Testing optionsORA-31626: job does not existORA-06512: at "SYS.DBMS_SYS_ERROR", line 79ORA-06512: at "SYS.KUPV$FT", line 405ORA-31638: cannot attach to job SYS_EXPORT_SCHEMA_01 for user SYSTEMORA-31632: master table "SYSTEM.SYS_EXPORT_SCHEMA_01" not found, invalid, or inaccessibleORA-00942: table or view does not exist
The steps to cleanup these failed/orphaned jobs are the same as mentioned above.