Tuesday, November 18, 2014

Oracle Virtual Technology Symposium: Download

For all those who attended my session today in Oracle Virtual Technology Summit on InMemory, thank you very much. Some questions were cut off towards the end since it was an automated session. I will be happy to answer, if your question was in that category.
Since this was an on-demand show, you can watch the replay anytime by visiting this site. Remember, this requires a connection to watch; it's not a download. You can download the slides from here and the scripts I used in the demo here.

Please post the questions you couldn't do during the webinar.

Monday, November 10, 2014

Cache Buffer Chains Demystified

You must have seen sessions waiting on the event “latch: cache buffers chains” from time to time. If you ever wondered what this means and how you can reduce time spent on it, read on. Here you will learn how buffer cache works, how Oracle multi-versioning works, how buffers are allocated and deallocated, what hash chain is and how buffers are linked to it, what the role of cache buffer chain latch is and why sessions wait on it, how to find the objects causing the contention and how to reduce the time spent on that event.

While exploring the reasons for the slowness in database sessions, you check the wait interface and see the following output:
 SQL> select state, event from v$session where sid = 123;

 ------- ---------------------------
 WAITING latch: cache buffers chains

This event is more common, especially in applications that perform a scan of a few blocks of data. To resolve it, you should understand what the cache buffers chains latch is and why sessions have to wait on it. To understand that you must understand how the Oracle buffer cache works. We will explore these one by one, and close with the solution to reducing the cache buffers chains latch waits.

Thursday, October 02, 2014

OOW14 Session: The Art and Craft of Tracing

A big thanks to all those who braved attending my session on the final day of Oracle Open World 2014. I hope you enjoyed it and found it valuable.

You can download the slide deck as well as the scripts I mentioned here.

As always, I would love to hear from you.

OOW14 Session: RAC'fying Multitenant

Thank you for attending my session RAC'fying Multitenant at Oracle Open World 2014. You can download the slide deck here.

[Updated] Oct 4th, 2014: The article on multitenant I wrote for OTN is available here. http://www.oracle.com/technetwork/articles/database/multitenant-part1-pdbs-2193987.html. This article shows various commands I referenced in my session, e.g. point in time recovery of PDBs.

As always I would love to hear from you.

Monday, September 29, 2014

OOW14 Session: SQL Tuning Without Trying

Many thanks to all those who attended my session "SQL Tuning without Trying" at Oracle Open World 2014 #oow14. I hope you found the session useful.

If you want to download the slide deck, here it is. As always, I would really, really like to hear from you.

OOW14 Session: Cache Fusion Demystified

Thank you all those who attended my session Cache Fusion Demystified.

As I mentioned, it was impossible to fit in a demo within that compressed 45 minute timeline. I put the details of the demo in a separate file with all the scripts and instructions that allows you to execute the demos at your own site.Download the slide deck as well as the scripts. In addition I have also written a whitepaper to explain the concepts clearer.

Download the slides, the paper, the demo scripts and instructions here.

I sincerely hope it demystified one of the most complex topics in Oracle RAC. As always, I would love to hear from you about your experience.

Sunday, September 28, 2014

OOW14 Session: Cache Buffer Chains Latches Demystified

Thank you all those who came to attend my session "Demystifying Cache Buffer Chains Latches" at Oracle Open World 2014. Much appreciated. I hope you got something out your time investment.

I have also written a paper to accompany this session. The paper explains the concepts I presented in greater detail. You can download a zip file containing the slide deck, the paper and the scripts here. Please note: this is a zip file.

And, yes, here is the blog entry that talka about why you need 7X memory to completely fit your database in buffer cache http://arup.blogspot.com/2011/04/can-i-fit-80mb-database-completely-in.html

As always, I would love to hear about your thoughts on the presentation.

One down at #oow14; five more to go :)

Saturday, September 27, 2014

My Small World at Oracle Open World 2014

Here is y speaking schedule at Oracle Open World #oow14. I have a whopping 6 sessions and one SIG. Don't have analyst meeting for a change. Yes, do have a customer reference.

1    1.       Sunday Sep 28th 11:00 Demystifying Cache Buffer Chains. Moscone South 309
2.       Monday Sep 29th 13:30 Understanding Cache Fusion Moscone North 130
3.       Tuesday Sep 30th 15:00 Exadata SIG Moscone South 208
4.       Tuesday Sep 30th 16:00 SQL Tuning Without Trying Moscone South 104
5.       Thursday Oct 2nd 9:30 RAC'ifyng Multitenant Moscone South 102
6.       Thursday Oct 2nd 13:15 Art and Craft of Tracing Moscone North 131
7.       Thursday Oct 2nd 14:30 Near Zero Downtime Migration, Intercontinental Grand Ballroom B

I hope to meet and say hello to many of you at one of these. if you can't make it. the preso, scripts and [possibly] whitepapers will be posted on my blog after the event. But, of course, do come. Looking forward to meeting you there.

And there will be tons of sessions I must attend, at #oow14 and Oak Table World.

Thursday, June 26, 2014

Sun Coast Oracle User Group June 24th Sessions Materials

Thank you to all those who stayed back quite late that night for my two presentations. I hope you found it informative and useful.

As promised, you can download the session materials here.

As always, I will be honored to hear from you.

Wednesday, June 11, 2014

Hadoop for Oracle Professionals Article on Oracle Scene

Oracle Scene (the publication of United Kingdom Oracle Users Group) has published my article "Hadoop for Oracle Professionals", where I have attempted, like many others, to demystify the terms such as Hadoop, Map/Reduce and Flume. If you were interested in Big Data and what all comes with understanding it, you might find it useful.

A PDF version of the article can be downloaded here http://www.proligence.com/art/oracle_scene_summ14_hadoop.pdf

Tuesday, June 03, 2014

NYOUG Summer 2014 Conference: Understanding Oracle Locking Internals

Thank you for all those who attended my session: Understanding Oracle Locking Internals today at the Summer 2014 conference of New York Oracle User Group in Manhattan. You can download the presentation and the scripts I used in demos here.

Presentation: http://www.proligence.com/pres/nyoug14/understanding_oracle_locking.pdf
Scripts: http://www.proligence.com/pres/nyoug14/understanding_oracle_locking_scripts.zip

As always, your feedback will be highly appreciated.

Friday, April 25, 2014

Creating Controlfile From Scratch when No Backup is Available

You have lost the controlfile, the catalog and the backup to the controlfile too; so restoring the controlfile from a previous backup is not an option. How can you recover the database? By creating the controlfile from scratch. Interested in learning how? Read on.

Thursday, April 24, 2014

How to Get the DBID when Instance in in NOMOUNT State

You lost your controlfile and the catalog. To restore the controlfile, you must know the DBID. Did you follow the advise to write down the DBID in a safe place? You didn't, did you? Well, what do you do next? Don't worry; you can still get the DBID from the header of the data files. Read on to learn how.

Tuesday, April 22, 2014

Restoring Controlfile When AUTOBACKUP Fail

Allow me to present the snapshot of a day from the life of John--the DBA at Acme Bank. On this particular day a database John manages crashed entirely and had to be restored from the backup. He takes regular (backupset) RMAN backups to tape. Since everything--including the controlfile--had crashed, John had to first restore the controlfile and then restore the database. The controlfile is always backed up with the backup database command. John was sure of that. However, restore controlfile from autobackup gave the error:
RMAN-06172: no AUTOBACKUP found or specified handle is not a valid copy or piece
Without the controlfile, the recovery was stuck, even though all the valid pieces were there. It was a rather alarming situation. Others would have panicked; but not John. As always, he managed to resolve the situation by completing recovery. Interested to learn how? Read on.

Thursday, April 17, 2014

Boston Oracle User Group Session: Oracle 12c Features You Should Know

Thank you for all those who attended the session, and braved it up to 10 PM. Much much appreciated.

Download the slides here, and scripts I used for the demos here.

As always, your feedback will be highly appreciated.

Friday, April 11, 2014

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
The Whitepaper
The Scripts (this is a zip file; so right click and Save As ...)

Needless to say, your comments and feedback will be highly appreciated. And, yes, please don't forget to do the evaluation on the Collab Mobile App.

Thursday, April 10, 2014

Collaborate14 Session: The Art and Science of Tracing

Thank you all for coming to my session "The Art and Science of Tracing" at Collaborate 2014. As I mentioned, I prepared a full session even though this is supposed to be a quick tip. I hope you enjoyed it and get the value from the full presentation deck.

You can download

The slide deck
The scripts (this is a zip file. Right click and then Save As ...)

As always, your feedback will be immensely appreciated.

Wednesday, April 09, 2014

Collab14 Session Should You Drop Indexes in Exadata?

Thank you all those who attended my 8:30 AM session at Collaborate 14 "Should You Drop Indexes in Exadata" (Session 316). I will appreciate receiving your feedback and giving it on the IOUG website and mobile app.

Here are material I presented. I have the slides here; but I suggest you download the paper as it is more standalone in nature.