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Database Feed

Oracle Database, Oracle 10g, Oracle 11g, Oracle XE, Oracle RAC, Oracle Instant Client, Oracle Data Guard and Oracle Exadata resources, news, and support articles.

adding NOT NULL columns to an existing table ... implications make me grumpy

This is DBA basics 101 in the oracle world but well also something that we grumpy DBA types forget from time to time.  We have an existing table in a schema that is populated with data.  Something like this say:

My New Oracle DBA batch from 21st April

Kanna Technologies Proudly announces next Oracle DBA Online Below are the course details: Faculty: Pavan Dba Demo: 14/04/0214 Start Date: 21/04/2014 Timings:08:30PM – 10:00PM IST Duration: 30 days Demo Link: Registration Link: Coupon Code: DB@T@L3NT Note: Early Bird Registrations will get 10% Discount.

Unique identifiers - but what do they identify

Most of the readers of this blog will be developers, or DBAs, who got the rules of Normalisation drummed into them during some phase of the education or training. But often we get to work with people who don't have that grounding. This post is for them. Feel free to point them at it.

enq: SQ – contention

This example shows how to deal with the enq: SQ – contention wait event. It was tested on Oracle 11.2.

Collaborate14 Session: Cache Buffer Chains Demystified

Thank you all for coming to my session Cache Buffer Chains Demystified at Collaborate 14, especially for sticking around for a geeky topic like this to the very end. Much appreciated.

I was not aware that I would not be allowed to use my laptop; so I couldn't show all the demos I so carefully prepared. Please download the scripts and execute them yourself.

As promised, here are the materials I used in the session

The Slide Deck

Keep Oracle VM server ethX name consistent across reboot

Jephe Wu - http://linuxtechres.blogspot.comProblem: random assigned ethX name with MAC address and renamed ethX to something else, different /etc/issue output after each rebootEnvironment: Oracle VM server 3.1.1, PCI card with multiple NIC portsSteps:1. use DRAC and lspci to check pci bus infoOpen DRAC, network device, check each MAC address for NIC2. draw network diagram for each NIC MAC address

Creating a DG Broker Configuration and Perform Swithover testing

1. Register Static service

To enable DGMGRL to restart instances during the course of broker operations, a static service must be registered In the listener.ora, the following entries should be presented:


Moving away from wordpress

I am sick of this advertisement on my site.

Therefor I am about to move most of my posts to


Thanks for following my blog for so long.

Lutz Hartmann

Portfolios on

Our new (free!) Portfolio tools and themes put your creativity front and center.

Oracle 12c Adaptive Plan & inflection point

12c Adaptive Plan feature has already been exposed by Nicolas Jardot in OOW 2013 : Solving customer issues with the 12c Optimizer

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