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Monday, December 14, 2015

Clean up objects and impdp/expdp jobs

Export Job Possible Statuses
Export job might be in several statuses:
- running
- orphaned table level export job
- stopped
- temporary stopped

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 /nolog
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

-- locate Data Pump jobs:

SELECT owner_name, job_name, operation, 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
SCOTT      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 active export/import Data Pump jobs. i.e. 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 'DROP TABLE '||OWNER_OBJECT||';' FROM
(
SELECT OBJECTS.status, 
       OBJECTS.object_id, 
       OBJECTS.object_type, 
       OBJECTS.owner||'.'||OBJECTS.object_name OWNER_OBJECT
  FROM DBA_OBJECTS OBJECTS, 
       DBA_DATAPUMP_JOBS JOBS
 WHERE OBJECTS.owner=JOBS.owner_name 
   AND OBJECTS.object_name=JOBS.job_name
   AND JOBS.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.EXPDP_20051121;
DROP TABLE SCOTT.SYS_EXPORT_TABLE_02;
DROP TABLE SYSTEM.SYS_EXPORT_FULL_01;

-- For systems with recycle bin additionally run:
PURGE DBA_RECYCLEBIN;

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:

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 

-- locate Data Pump jobs: 

SELECT owner_name, job_name, operation, 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 OBJECTS.status, 
       OBJECTS.object_id, 
       OBJECTS.object_type, 
       OBJECTS.owner||'.'||OBJECTS.object_name "OWNER.OBJECT"
  FROM DBA_OBJECTS OBJECTS, 
       DBA_DATAPUMP_JOBS JOBS
 WHERE OBJECTS.owner=JOBS.owner_name 
   AND OBJECTS.object_name=JOBS.job_name
   AND JOBS.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_JOBS 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.

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