Tag: Group Blog Posts

Character Set Conversion 10g and 11g – Part 1

This post is the first in a series of discussions … perhaps you have never had the pleasure of needing to change a character set. If you have not and soon do, purchase a good sleeping bag as you may be at the office late for a few days to get the task accomplished.

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Upgraded to 11GR2? Congrats! You Are in Direct Reads Trouble!

I made this blog title intentionally provocative. However it isn’t far from the truth. Don’t believe me? Continue reading :)

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Case Study: How to Return a Good SQL Execution Plan from 10g Days After an 11g Migration

Any database upgrade suppose to change SQLs’ execution plans for the better. In 99 cases out of 100 this is exactly what happens. What to do with rest 1% of the SQLs? This blog post is exactly about such unlucky case I have resolved today. Hope that you will learn something out of it. As always let me know what you think using the comments section at the end of the post.

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Log Buffer #293, A Carnival of the Vanities for DBAs

Like every year, Pythian is once again holding a company-wide charity campaign to raise funds and awareness for for men’s health, specifically prostate cancer and male mental health. Sporting and sprouting the mustaches has already begun at Pythian and the game is on. While that happens, blogging fanfare also continues and this Log Buffer Edition in its Log Buffer #293 covers that and more.

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Select Statement Generating Redo and Other Mysteries of Exadata

Like many good stories, this one also started with an innocent question from customer: “I often check “SELECT COUNT(*) FROM TABLE;” on our old 10.2.0.4 cluster and the new Exadata. The Exadata is slower than our old cluster by few minutes. Exadata is not good at count(*) ? or other problem?” Here’s how I fixed it.

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Reasons to Use ASM on NFS

My tweet few days ago – “Personally I don’t see the point building ASM on (d)NFS. ASM suppose to exclude unnecessary layers. In NAS case it adds an additional layer.” Since then Oracle people in my Social Media environment helped me to find several legitimate reasons to run ASM on NAS. Thank you folks very much. Now I am sharing our common thoughts with the rest of the community.

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Oracle Direct NFS Configuration File Explained

While Oracle tech folks doing their best to explain meaning of not so many DNFS configuration file (oranfstab) parameters I still find an official description a bit confusing. Therefore I decided to share my understanding of the DNFS configuration parameters in hope that it will help someone or if my understanding is wrong someone corrects me :) So, if I am wrong please please please feel free to leave comments.

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DUPLICATE from ACTIVE Database Using RMAN, a Step-by-Step Guide

In this guide assume we are migrating a single instance database HRDEV to a two node RAC database HRPRD with following specifications.

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Silent Installation of EM Cloud Control 12c

Silent installation always attracts by its simplicity and power, the new release 2 of EM 12c proves it, making installation
smooth and straightforward. Before we start the installation, it is very important to make sure all prerequisites are satisfied
to avoid any unpredictable errors during the process. Let’s have a look.

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Repost: Oracle Protocol

Ian Redfern published a paper documenting the TNS protocol internals. The paper is titled “Oracle Protocol” and is clearly the result of painstaking research.. the paper became a classic in our field. Fortunately, it was released into the public domain, allowing me to reproduce it here in full, preventing it from disappearing forever.

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