Oracle Silent Installation

In this Blog i will guide you to perform silent installation i.e. without using oracle installation GUI page.

Benefits:
Silent Installation is very much useful to avoid slowness caused by memory thirsty java GUI pages
Its is performed from command line & allows great control over installation steps
Less time consuming if re-start of the installation required
No hectic X-Window configuration

Background:
Silent installation method i have used for the first time while patching 10g (10.2.0.1) oracle home with 10.2.0.5 patch , it was very critical situation when i sat down for a production database 10205 upgrade & little bit over confident that GUI has to work while patching existing 10201 oracle home with 10205 as it worked in test environment .

Only different condition was that i was doing this activity from home via a VPN.

It was 5 Hrs of downtime , first 1 Hrs 30 min i struggle to open xclock itself which is basic GUI testing tool used before opening any GUI. Finally i gave up.I Called up my manager that i am unable to perform it , he suggested/reminded few steps to open GUI but that also failed , till then i had lost almost 2 Hrs of 5 Hrs downtime.


RMAN Backup Restoration example

This blog will guide you through the basic steps of Backup , Restoration & Recovery Using RMAN

Step1 : Online RMAN datafile , control-file & archive-log Backup at Source(MW4-S)
Step2 : Configuring Destination (IEWE-S) database server for restoration & recovery
Step3 : Starting up the instance at destination in nomount
Step4 : restoring control-file
Step5 : Cataloging Backup-sets
Step6 : restoring datafiles
Step7 : Recovery & Open resetlogs


MW4-S is the source database server & IEWE-S is destination where database will be cloned
Environment used is Oracle11g & OS platform Solaris 10 

Let's begin then ..

Step1 : Online RMAN datafile , control-file & archive-log Backup at Source(MW4-S)
Database should be in mount or open mode as a prerequisite of RMAN backup because in the absence of recovery catalog control file is the source of metadata to identify file locations & SCN (system change number , for consistency check)

Import dump using pipe



Background:


Same as export using pipe, import can be done by following below steps

Import using Pipe

Step1
Create nods equal to dump files & point it to a pipe

mknod /u01/orabak/export/imp_pipe1 p
mknod /u01/orabak/export/imp_pipe2 p
mknod /u01/orabak/export/imp_pipe3 p

Export dump compression using pipe

This post will help you to run traditional export import backup utility with compression


Background:
Although compression is supported by imp/exp but it is limited to segment extents only & does not solve the purpose.
It will be very much difficult to perform export import operations where db servers holding less space on local file system to keep dump files

Performing export import over network could be a workaround to this issue but due to network delay it could become more tedious

Export/ Import using mknod or pipe will help to zip/unzip the dump files during export or import operation respectively without specifying it explicitly

New 10g (onwards) feature Data Pump COMPRESSION is replaceable with the mknod export/ import method

Export Import Pipe should be used in pre-10g environments to reduce actual export import time, OS space usage & to minimize delay in transport of dump files across the db servers due to less size of the dump

Let us see how it works in export import operation with single & multiple dump files

Truncating table in DB2



Surprised!! How come DB2 blog in Oracle Arena?

Well just a command I want to introduce which has helped a lot to my DB2 DBA’s
How to truncate a table in DB2?

This was the question on everyone’s mind in crisis time

Table was sizing almost over 10GB growing continuously; generating transaction logs (same as our archive-log in our oracle) 

Rows Deletion in turn added fire in the storm, causing huge number of transaction logs with mount point nearing to panic level threshold

Just a thought came in the mind to ask DB2 DBA to truncate the table, being core DBA support no table level operations were known

Connectivity Jdbc & oracle database Troubleshooting java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver



This blog will allow DBA’s to troubleshoot connectivity between Jdbc & oracle database

It will also help to tackle common Java connectivity errors like below in windows environment where tracing/debugging is very difficult  

java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at bpos.Db.Conectar(Db.java:20)
at bpos.Process.main(Process.java:19)

SQL*Net message to dblink , SQL*Net message from dblink

This blog is written based on the issue faced due to huge response time of sql query waiting on dblink.

Issue:
Query responding in almost 5 min with session wait event of SQL*Net message to dblink / SQL*Net message from dblink



Analysis:

T3157 was a view calling one more view XXECMS_SM_DTLS_VL_ATS

Observing the DDL of XXECMS_SM_DTLS_VL_ATS it has been identified that it is formed with a complex query having remote references via db link.

Each table being referred over db link was holding more than 50 lac records & sizing over 4 GB each.

Becoming an Oracle DBA




Friends! Let me greet you for having interest in such a wonderful profile of IT, Oracle DBA.

More the Knowledge you have, more the Experience you will gain!
More the Experience you will have, more the Respect you will earn!
Respect will motivate you for great career ahead!!

You might have visited this blog with atleast any of these 10 questions in your mind, Let me guess & answer it one by one for you

  1. Why to become DBA?      
  2. Why to become Oracle DBA?            
  3. Who can become Oracle DBA?
  4. What is Oracle Database?     
  5. How to become Oracle DBA?         
  6. Responsibility of an Oracle DBA?                              
  7.  Life of an Oracle DBA?             
  8. Risks involved?                                    
  9. Advantage?
10. Becoming Master of Oracle DBA?