Databases

Here is a short list of new articles you may expect to see here in a month's time. if you have any specific request, please send an email using the "contact us"  page.

1. install 11g on ubuntu and fedora (latest releases)

2. Install 11g on windows

3. Upgrade 10.2 to 11.1 and then to 11.2 on linux

4. Data dictionary changes in 11G -- whats new.

execute dbms_workload_repository.modify_snapshot_settings ( interval => 10,retention => 14400000);

Note: retention and interval are in minutes

To manually create a snapshot:

execute dbms_workload_repository.CREATE_SNAPSHOT;

Note: This article is intended to provide you an overview of the installation process. Please do not use this as reference for installing a production system. These instructions are purely for educational purpose only.

You are doing your rman backup to tape. And lets say that you are trying to restore the database that was backed up to tape. So, what tapes do we need to recall ? Here’s the query to find the tapes that you need to recall.

set heading off  
column TAPE format a15 trunc  
column LEVEL format 99999  
column TYPE format a4 trunc  
select SET_COUNT, MEDIA as "TAPE",  
to_char(START_TIME, ‘MM/DD/YYYY HH24:MI:SS’) as "BACKUP TIME",  
INCREMENTAL_LEVEL as "LEVEL", BACKUP_TYPE as "TYPE"  
from RC_BACKUP_PIECE  
where DB_KEY=  
(select DB_KEY from RC_DATABASE_INCARNATION where CURRENT_INCARNATION=’YES’  
AND NAME=’<DB_NAME’)  
and START_TIME > to_date(’07/15/2007 20:00:00′, ‘MM/DD/YYYY HH24:MI:SS’);

Opatch FAQs and Tips

====================  
[This guide is inteded to provide a brief overview of the OPatch utility and you should always refer to the official documentation released by oracle corporation for latest information]

OPatch is a java based utility that allow the application and rolling back of interim patches to an Oracle product. The program has sub-commands that  
may take arguments. The program requires Java(JVM) to be present on the current system.OPatch expects users to have commands such as fuser, jar, ar and make on  
Unix platforms and jar on Windows platforms to be available in their PATH.

Help : $ORACLE_HOME/OPatch/docs/Users_Guide.txt

Trouble in Installing/Re-Installing Oracle Client Software?

1. What to do if you face any of these problems:

• My Oracle client installation hangs at xx% and nothing happens.
• Oracle client installation shows successful but I get an error while trying to run SQL*Plus that some DLLs are missing.

2. I am not able to successfully reinstall the oracle client software.

Possible Solution:

Preface

Often we need to copy users/roles from one database to other database especially when you are deploying a new application to a higher environment. Below are 2 scripts which can generate scripts for you to build the roles and users. You can modify these scripts to generate scripts for multiple users at the same time by changing USERNAME= or ROLE= to USERNAME in (”.”) or ROLE in (”,”) respectively.

Contributed by : Nanie Asedillio

Backup the primary database using RMAN.

Setup the standby directory structures similar to Primary and create the init.ora

#Standby specific Configuration  
*.fal_client=’MYDB_S’  
*.fal_server=’MYDB_P’  
*.log_archive_dest_1=’LOCATION=/export/oracle/archive/MYDB/log mandatory’  
*.log_archive_dest_2=’SERVICE=MYDB_S optional reopen=60′  
*.log_archive_dest_state_1=’ENABLE’  
*.log_archive_dest_state_2=’DEFER’  
*.service_names=’PRODCDW’  
*.standby_file_management=’AUTO’  
*.standby_archive_dest=’LOCATION=/export/oracle/archive/MYDB/log’  
log_archive_format = ‘arch_%t_%r_%s.dbf’  
log_checkpoint_interval = 0  
*.aq_tm_processes=0

Enable the Flashback Recovery

Step 1: Add the initialization parameters

Open the init.ora file and add following parameters:

*.db_recovery_file_dest='/app/oracle/product/flash_recovery_area'
*.db_recovery_file_dest_size=2G
*.db_flashback_retention_target=10080   # Represents 7 days (60 minutes*24*7)

Note: DB_FLASHBACK_RETENTION_TARGET specifies the upper limit (in minutes) on how far back in time the database may be flashed back. How far back one can flashback a database depends on how much flashback data Oracle has kept in the flash recovery area.