Full table scans internals

[blip.tv http://blip.tv/play/AYLNmlEC%5D

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RAC Hacking Session by Riyaj Shamsudeen


RAC Hacking Session: Probing LMS Process Internals With Advanced UNIX Utilities from poderc seminars on Vimeo.
A deep dive discussion about the LMS background process (global cache service). Riyaj will show you the techniques that he use to study the behavior of RAC processes. For this session, he’ll probe the internals of the LMS process using DTrace, truss, and other advanced UNIX utilities. After attending this session, you’ll understand the inner workings of the LMS process better and you’ll learn to do your own probing at home too (try it at home and not in a production system! 🙂

E-Business Suite Performance Tuning

I was going through Steven Chan’s blog and have got a very good presentation on EBS performance tuning. It has given the approach, note references and tools to be used during investigation. It covers all the aspects of the system – client browser, middle-ware, network and database. It is a must reference for all the Oracle Apps DBAs.

Apart from the tools mentioned – I strongly recommend to use ASH Viewer and Tanel Poder’s Snapper when tuning database.

Presentation (pdf 1.9M)

Source: http://blogs.oracle.com/stevenChan/entry/oaug_collaborate_recap_best_practices

Add Colors to Terminals, Get Life

It is so much boring seeing your mono colored puTTY sessions. Though there is no way to fill your life with colors if you are ksh lover, because there is no such way in solaris. You need to get to kid level to see colors.

anjul@nebula:/home/anjul$ cat .bashrc
export PS1="\e[0;32m\u@\h \w> \e[m"
# Define a few Color's
BLACK='\e[0;30m'
BLUE='\e[0;34m'
GREEN='\e[0;32m'
CYAN='\e[0;36m'
RED='\e[0;31m'
PURPLE='\e[0;35m'
BROWN='\e[0;33m'
LIGHTGRAY='\e[0;37m'
DARKGRAY='\e[1;30m'
LIGHTBLUE='\e[1;34m'
LIGHTGREEN='\e[1;32m'
LIGHTCYAN='\e[1;36m'
LIGHTRED='\e[1;31m'
LIGHTPURPLE='\e[1;35m'
YELLOW='\e[1;33m'
WHITE='\e[1;37m'
NC='\e[0m'              
# No Color
echo -e "${LIGHTBLUE} Hello ${RED} ${USER}, ${CYAN}Welcome back to NEBULA"

Unable to add columns in a table

SQL Error Adding multiple column in one batch

HY000 (22856): [DataDirect][ODBC Oracle driver][Oracle]ORA-22856: cannot add columns to object tables

This is the error you get when adding columns to a compressed tables in Oracle 9i. This is a bug (#2421054) documented on Oracle Support (Doc. ID 217292.1).
Solution:

  1. Take the backup preferably export *dump* of table.
  2. Take the script backup of indexes and table.
  3. drop the table.
  4. create the table with nocompress option (alter table nocompress)
  5. import the *dump* with ignore=y option. Now you can add columns, this error specifically can be seen during Siebel DDL sync activity.