Moving to WordPress...

Well, so many friends and well wishers asked about bijoos.com - so put the site back [though most of the stuff is obsolete] and moved the blog to http://bijoos.com/oraclenotes

I will try to keep the blog active...

Thanks for visiting...

Have a great day!

Active or Recently Used Printers in Oracle EBS

Recently had a request from one of the admins for list of printers used in the EBS application and how many jobs are directed to a printer. The following SQL provided what the admin needed, thought a good one to share...

select distinct fcr.printer, fu.user_name, 

       fu.description, count(*) jobs

from apps.fnd_concurrent_requests fcr, apps.fnd_user fu

where fcr.requested_by = fu.user_id

and (fcr.printer is not null and fcr.printer not in  ('noprint','LOCAL_PRINT','LOCAL','LOCAL_PRINTTO', 'LOCAL_PREVIEW'))

group by fcr.printer, fu.user_name, fu.description;

The caveat is that if you purge concurrent requests, the information is dependent on the records available in concurrent requests table...

Hope this helps someone, or if there is a better way to find the printer usage, please let me know... have a great day!

Using Flashback during repeated load tests

We are in the middle of migrating several databases to a new data center. One of the requirement is to do rigorous load and stress tests on the new servers to make sure they can handle the load and the configuration is correct. For this purpose, there are several load/stress test scripts are written and tested using OATS [Oracle Application Testing Suite].

Since the load/stress tests are done repeatedly, the test data [database] need to be restored to its pre-test state before doing the next test. As these database sizes are large, it will take a while to do the restore. But, the flashback feature of the database comes handy.

Enable Flashback

To enable flashback, from 11gR2 onward there is no need to restart the database in mount mode. Flashback can be enabled and disabled while the database is online.

Before you enable flashback, set the following parameters.


SQL> show parameter recovery

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      +ORAARCH
db_recovery_file_dest_size           big integer 50000M

Enable flashback using:

SQL> ALTER DATABASE FLASHBACK ON;

You can verify if flashback is enabled by querying v$database.

SQL> select flashback_on from v$database;
FLASHBACK_ON
------------------
YES

Flashback logs are written to the directory speficied by the DB_RECOVERY_FILE_DEST parameter. The retention of these files depends on the setting of parameter:

SQL> show parameter db_flashback

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_flashback_retention_target        integer     1440

SQL>

The database must be in ARCHIVELOG mode.

Create Restore Point

During load/stress tests we like to make sure the database is flashbackable to pre-test state. We ensure this by creating a guaranteed restore point.

SQL> create restore point BEFORE_LOAD_TEST_G GUARANTEE FLASHBACK DATABASE;

Restore point created.

SQL>

Restore points created in the database can be viewed from v$restore_point view.

SQL> SELECT NAME, SCN, TIME, DATABASE_INCARNATION#,

       GUARANTEE_FLASHBACK_DATABASE

      FROM   V$RESTORE_POINT ;

NAME                         SCN                             TIME DATABASE_INCARNATION# GUA

---------------------- ---------- ------------------------------ --------------------- ---

BEFORE_LOAD_TEST_G       51274755 26-NOV-12 02.52.04.000000000 PM                     2 YES

You will have to keep track of the space usage on the flash recovery area to make sure you have enough free space. 

SQL>  select * from V$FLASH_RECOVERY_AREA_USAGE;

FILE_TYPE            PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE NUMBER_OF_FILES

-------------------- ------------------ ------------------------- ---------------

CONTROL FILE                          0                         0              0

REDO LOG                              0                         0              0

ARCHIVED LOG                      18.47                         0            218

BACKUP PIECE                          0                         0              0

IMAGE COPY                            0                         0              0

FLASHBACK LOG                     12.24                         0             15

FOREIGN ARCHIVED LOG                  0                         0              0

7 rows selected.

SQL>

After the test is done, it is time to flashback!

Flashback the Database

To flashback, the database has to be restarted in mount state. Here the example shows a RAC database shutdown and startup.

$ srvctl stop database -d mydb

$ srvctl start instance -d mydb -n mynode1 -o mount

Use RMAN to do the flashback, the advantage is that if any archivelog that is not present in the disk is required for flashback recovery, RMAN can automatically restore the archivelogs from the backup media.

$ rman target /

RMAN has commands to list the restore points in DB.

RMAN> list restore point BEFORE_LOAD_TEST_G;

using target database control file instead of recovery catalog

SCN              RSP Time  Type       Time      Name

---------------- --------- ---------- --------- -------------------

51274755                   GUARANTEED 26-NOV-12 BEFORE_LOAD_TEST_G

Now ready to flashback the database...

RMAN> FLASHBACK DATABASE TO RESTORE POINT BEFORE_LOAD_TEST_G;

Starting flashback at 27-NOV-12

using target database control file instead of recovery catalog

allocated channel: ORA_SBT_TAPE_1

channel ORA_SBT_TAPE_1: SID=997 instance=prod2 device type=SBT_TAPE

channel ORA_SBT_TAPE_1: Veritas NetBackup for Oracle - Release 7.5 (2012091607)

allocated channel: ORA_SBT_TAPE_2

channel ORA_SBT_TAPE_2: SID=1139 instance=prod2 device type=SBT_TAPE

channel ORA_SBT_TAPE_2: Veritas NetBackup for Oracle - Release 7.5 (2012091607)

allocated channel: ORA_SBT_TAPE_3

channel ORA_SBT_TAPE_3: SID=1281 instance=prod2 device type=SBT_TAPE

channel ORA_SBT_TAPE_3: Veritas NetBackup for Oracle - Release 7.5 (2012091607)

allocated channel: ORA_DISK_1

channel ORA_DISK_1: SID=1424 instance=prod2 device type=DISK

starting media recovery

archived log for thread 1 with sequence 169 is already on disk as file +ORAARCH/prod/archivelog/2012_11_26/thread_1_seq_169.482.800375559

archived log for thread 2 with sequence 500 is already on disk as file +ORAARCH/prod/archivelog/2012_11_26/thread_2_seq_500.480.800373637

media recovery complete, elapsed time: 00:00:04

Finished flashback at 27-NOV-12

RMAN>

RMAN> alter database open resetlogs;

database opened

RMAN>

Database flashback is done!

You may now start the other instances in the cluster, if applicable.

$ srvctl start instance -d mydb -n mynode2

Flashback using time, instead of restore point.

Sometimes, it is required to flashback a database without a restore point - to a time. It can be done using the syntax:

If you are restoring to a time, instead of restore point, use the below syntax.

RMAN> flashback database to time "to_timestamp('2012-11-29 12:00:00', 'YYYY-MM-DD HH24:MI:SS')";

Starting flashback at 30-NOV-12

using channel ORA_SBT_TAPE_1

using channel ORA_SBT_TAPE_2

using channel ORA_SBT_TAPE_3

using channel ORA_DISK_1

starting media recovery

channel ORA_SBT_TAPE_1: starting archived log restore to default destination

channel ORA_SBT_TAPE_1: restoring archived log

archived log thread=2 sequence=56

channel ORA_SBT_TAPE_1: restoring archived log

archived log thread=1 sequence=36

channel ORA_SBT_TAPE_1: reading from backup piece PROD_1211301159_AL0_501_1_1_800714350

channel ORA_SBT_TAPE_1: piece handle=PROD_1211301159_AL0_501_1_1_800714350 tag=DS1PROD2_1211301159_AL0

channel ORA_SBT_TAPE_1: restored backup piece 1

channel ORA_SBT_TAPE_1: restore complete, elapsed time: 00:00:45

channel ORA_SBT_TAPE_1: deleting archived log(s)

archived log file name=+ORAARCH/prod/archivelog/2012_11_30/thread_1_seq_36.794.800732539 RECID=652 STAMP=800736143

channel ORA_SBT_TAPE_1: deleting archived log(s)

archived log file name=+ORAARCH/prod/archivelog/2012_11_30/thread_2_seq_56.792.800732539 RECID=651 STAMP=800736142

media recovery complete, elapsed time: 00:00:04

Finished flashback at 30-NOV-12

RMAN>

RMAN> alter database open resetlogs;

database opened

RMAN>

Disk Array Migration for ASM Databases

This blog identifies the DBA steps required to migrate databases from one disk array to another.

Identify the ASM diskgroups and their disk (LUN) sizes

Login to the ASM instance and identify the LUNs allocated to server.

SQL> SET PAGES 999

SQL> col name format a15

For 11g ASM:

SQL> select d.group_number, g.name, d.os_mb

from v$asm_disk d left outer join v$asm_diskgroup g

on (d.group_number = g.group_number)

order by g.group_number, d.os_mb;

For 10g ASM:

SQL> select d.group_number, g.name, d.total_mb

from v$asm_disk d left outer join v$asm_diskgroup g

on (d.group_number = g.group_number)

order by g.group_number, d.total_mb;

You may discard LUNs with group number 0, as they are not part of any diskgroup. Request Sysadmin team to provision the new LUNs to the container, same LUN size or total of multiple LUNs in the group is equal or more to what is allocated to the group. 

 To find out what is allocated and free in each diskgroup, you may use:

SQL> select name, total_mb, free_mb from v$asm_diskgroup;

Once LUNs are provisioned by Unix team, use OEM or SQL to add the LUNs to respective diskgroups [existing diskgroup]. NO outage required for this step. Remember to login to 11g ASM using the SYSASM privilege, for 10g login using SYSDBA privilege.

SQL> ALTER DISKGROUP ADD DISK ‘/full_path_of_device’;

To find out which LUNs are available to add, you may use SQL:

SQL> col path format a40

SQL> select path, os_mb from v$asm_disk where group_number = 0;

{for 10g ASM, please substitute os_mb with total_mb}

Then, go ahead and drop the old LUNs. No need to wait for the add operation to complete.

SQL> ALTER DISKGROUP DROP DISK name_of_old_LUN;

The name of the LUN can be found by querying the V$ASM_DISK...

SQL> select path,name from v$asm_disk where group_number=3;

Keep the rebalance power low, so that the migration activity does not impact database performance.

You may check the progress of rebalance periodically using V$ASM_OPERATION, once no rows are in this view, you may advice SYSADMIN team to pull out the old LUNs from the server. V$ASM_OPERATION also shows the work so far completed and how long it will take to complete the work.

SYSAUX Tablespace Growth - Review and Fix

Received an alert from one of the databases that SYSAUX tablespace is nearing its allocated 24GB space. 24GB is too much for SYSAUX, especially on a development database... so need to make sure the contents are reviewed before adding more space...

Oracle10g+ versions have a view V$SYSAUX_OCCUPANTS, showing what components are in SYSAUX tablespace and how much space is used. It also shows the procedure to use if you decide to move this component from SYSAUX to another tablespace.



SQL> col OCCUPANT_NAME format a20

SQL> select occupant_name, space_usage_kbytes

     from v$sysaux_occupants
     where space_usage_kbytes > 10240
     order by space_usage_kbytes desc;

OCCUPANT_NAME        SPACE_USAGE_KBYTES
-------------------- ------------------
SM/AWR                          2875776
LOGMNR                           573184
SM/ADVISOR                       448384
XDB                              177216
SDO                               79936
STREAMS                           76928
AO                                49536
XSOQHIST                          49536
XSAMD                             31872
SM/OTHER                          17984
TEXT                              14720

11 rows selected.

SQL>

So, it really does not add up anywhere near 24GB, the largest component is AWR and is only occupying less than 3GB... What else is in SYSAUX, that does no belong to the standard Oracle components?


SQL> col SEGMENT_NAME format a25
SQL> col segment_type format a10
SQL> col bytes format "999,999,999,999"
SQL> select segment_name, bytes 
     from dba_segments 
     where tablespace_name = 'SYSAUX'
     and bytes > 1048576000 order by bytes;

SEGMENT_NAME                         BYTES
------------------------- ----------------
SYS_LOB0002516712C00008$$   20,408,434,688

1 row selected.

SQL>

It's a LOB segment, let us find out which table...

SQL> select table_name, column_name

  2  from dba_lobs

  3  where segment_name = 'SYS_LOB0002516712C00008$$';

TABLE_NAME

------------------------------

COLUMN_NAME

---------------------------------------------

STREAMS$_APPLY_SPILL_MSGS_PART

MESSAGE

Aaaha! We recently enabled Change Data Capture feature on this database, and it is using STREAMS... Now, need to see what's causing it to grow and how to fix...!

Also, shows that V$SYSAUX_OCCUPANTS do not consider the LOB segments, when calculating space occupied  :-(