Pythian Group

I have a confession to make: I hate webinars. I find it difficult to concentrate on a disembodies voice. I typically get distracted and find myself checking email and blogs even during the best webinars. Watching a webinar is a bit like watching DVD of a live show – not as fun as live show, and not as polished as a music video.

But one can’t escape the fact that webinars are quickly becoming a very popular learning method. The best presenters I know are giving webinars and every DBA uses them to improve his knowledge. I’m happy to report that despite the fact that I sat alone in a room and talked to my cat about ODA performance for a full hour the presentation went rather well.

If you are interested in the topic but missed the webinar or if you want to hear it again, you can view our recording.

I also uploaded the slides to slideshare, so you can take a better look at our benchmark results and study our consolidation methods at your own pace. Unfortunately, Slideshare mangled few of the slides, so if they look unclear you can use the recorded webinar to disambiguate.

There were few questions I did not have time to address during the webinar. Interestingly enough, many of them have nothing to do with ODA but are rather about my benchmarking methods.
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During last couple of month I was seeing some discussion and question in different online conferences and user groups about upgrade RAC and exadata to 11.2.0.3. The questions were mostly about upgrade procedure, timing, what can happen during the upgrade and how a system behaves after upgrade.

I’ve recently upgrade couple of exadata to 11.2.0.3 and want to share the experience. I hope this short note will help someone to make the decision, calculate estimation and prepare for maintenance. I am going to talk about upgrade from the version 11.2.0.2 BP10 to 11.2.0.3 BP2.

I. Preparation:
First, you need to read thoroughly oracle support note [ID 1373255.1] (strongly recommended as a primary guidance for the upgrade), make a general plan and calculate estimation time for every upgrade step. Most of the steps can be done in rolling mode and don’t require full downtime for the environment.

The second step is about gathering information about your current system and checking if your firmware and exadata software versions fulfill the requirements for 11.2.0.3.

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The website for Oracle Database Cloud Services at cloud.oracle.com is now online, in conjunction with Larry Ellison’s announcement during the Oracle OpenWorld keynote going on now. It’s a hosted database service running Oracle 11gR2. The database can be accessed using a hosted Oracle application server, via JDBC across the Internet, or their own RESTful API a la Amazon. Notably lacking is Oracle’s own TNS network protocol.
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PYTHIAN NEWS

Pythian is happy to announce today the achievement of three new Oracle PartnerNetwork Specializations bringing the total to seven under our Platinum level membership of the Oracle PartnerNetwork (OPN) program.

Now added to the list are Oracle Exadata, Oracle Data Warehousing, and Oracle GoldenGate.

Complementing the added specializations is Pythian’s launch of new Oracle Exadata-focused products and services including an Oracle Database 11g Release 2 migration calculator, Oracle Exadata Smart Flash Cache Monitoring Tool, and an Oracle Exadata Managed Services program that extends the company’s Oracle Exadata-readiness services.

Pythian’s most recent Oracle Exadata clients include a major financial services company in New York and an e-commerce company specializing in data aggregation for the travel industry. Pythian’s Oracle GoldenGate expertise is supporting Western Union currently.

• Read the PR about our newest Specializations
• Read about our first series of Specializations
• Hear us our Specialized experts in person at OOW11

To find out how we can put our specialized Oracle expertise to work for you, contact us, send us an email or call 1-866-798-4426 ext. 2.

This post is long overdue, as I was supposed to blog about my appearance at NoCOUG before I left (sorry, Vanessa!). However in my efforts to rehearse and adjust my presentation, blogging about it just fell to the wayside. However now that NoCOUG 2011 Summer Conference is in the books, I’d like to take a few minutes to share my experience not only as an attendee, but also as a first-time speaker.

When I found out that NoCOUG had accepted my abstract, “Oracle 11g: Learning to Love the ADR”, I was both ecstatic and terrified. This meant that I actually had to prepare the presentation and speak in front of peers. Surely they would throw me into San Francisco Bay if I didn’t bring my A-game, so I set out to do just that.
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No, this isn’t a re-post of my earlier blog about bug 1233183.1. We’ve found a fun new bug that seems to be specific to our poor standalone ASM instances when upgrading from Oracle Grid Infrastructure 11.2.0.1 to 11.2.0.2.

The bug was first brought to my attention about four days after completing the Grid Infrastructure upgrade. The client system administrator (SA) noticed that the disk holding the Oracle home directories was slowly filling, at the rate of about 1Gb per day. We identifed that core dump files being created under the new GRID_HOME/log//diskmon/ directory, at the rate of about 1 every 10 minutes, each one about 8M in size. That adds up to 1152M (or just over 1Gb) per 24-hour day. Add that to the 8Gb that was being held in GRID_HOME/.patch_storage (we had to rollback the 11.2.0.1 April 2010 PSU and apply the 11.2.0.1 July 2010 PSU just to upgrade to 11.2.0.2), and that put a bit of a squeeze on the free disk.

The good ol’ OTN forums led me to bug 10283819. The original poster there shared also that removing the old (11.2.0.1) grid home directory and restarting diskmon services stopped the core dump creation. The poster then went to question a second issue with increased diskmon.log writing. After a solution was found for that, Oracle Support closed the bug for some reason, without ever addressing the core dump creation.

I can verify that removing the old 11.2.0.1 grid home (I did a tar+bz2 first) and restarting the services did stop the core dump creation, and am pushing back to Oracle support to get the bug re-opened or a new bug filed to specifically address this. In the meantime, if you are unable or unsure about removing the old grid infrastructure home, it should be safe to have a regularly scheduled script remove the diskmon core dump directories and save you a full disk surprise late some night.

A very warm welcome to the Log Buffer, the premier medley of fresh information culled from the blogs related to the technology which stores the world, yes, the databases.

In this edition, the Log Buffer #205, we have yet again found the pulse of the industry.

Oracle:

On the Oracle front, leading Oracle technologist Andrey Goryunov carries on his hands-on experiments of newest version of the Oracle database. This time he slices away chopt.

It’s always very informative and exciting to know about internals of RAC Stuff like what actually is maintained in the Voting Disk . Riyaj has it here.

Jonathan Lewis does a little thought experiment with list partitioning.

HugesPages almost always provide value to the Oracle databases on the Linux Systems, and many people wonder why they are not the default. Kevin Closson touches some points regarding HugesPages, and he also notes down some finer points like the dislike of AMM and Hugespage for each other.

Hardly anyone would refuse a gift consisting of chocolate, ice cream, flower and designer watch. Yes, now you can have Tanel Poder, Cary Millsap, Jonathan Lewis, and Kerry Osborne at one Virtual Oracle Conference.

Tim Hall, like many other people is perturbed over the plagiarism of his articles.

Oracle recommends that you use JRockit JDK with your Oracle products and the reasons are described by JaySenSharma at his Weblogic Wonder blog.

DB2:

Now, RPM and DEB packages for DB2 Express-C are available for the download. Get it from here.

Troy Coleman, blogs about the ripple-creating news that Last week IBM announced the general availability of DB2 10 for z/OS.

The keynote session for the third day of the IOD conference features the authors of Freakonomics, Steven Levitt and Stephen Dubner, and Craig Mullins highly recommend that.

SQL Server:

If you are curious about the title “Plumbing The Depths of SQL Server / PowerShell Integration, then don’t miss SQL Server Connections conference on Nov 1-4 in Las Vegas and attend the session by Bob Beauchemin.

Though not earth-shattering and sky-ripping, but very valuable nonetheless this post by Jeff about calculating the median.

And following is the ever-green SQL Server Myth buster posts by Euan.

MySQL:

Zack Urlocker rambles on how open source software, cloud and software as a service are helping to bring about the consumerization of IT.

Here is one more effort where the bencmarking of MariaDB is being done.

Have a nice weekend.

Welcome to Log Buffer, the weekly roundup of happenings in the database world.

Lots to cover this week, so let’s get on with Log Buffer #204. Enjoy!

Oracle:

Pythian’s Gwen Shapira dabbles with MySQL and explores MySQL troubleshooting for the Oracle DBA.

Venkat Janakiraman explores how connectivity works for BI EE 11g on Microsoft SQL Server Analysis Services 2008.

Iggy Fernandez explores SQL 101: Which Query is better, in part II to a post he covered in summer of this year.

Chet Justice, on Oraclenerd reviews how to use forgotten function OBIEE: Evaluate

Tanel Poder announces last chance for early-bird rates to sign up for the virtual conference on Systemic Oracle SQL Optimization featuring himself, Cary Millsap, Jonathan Lewis & Kerry Osbourne.

DB2:

Lots going on at the IOD 2010 conference over the past week. Craig Mullins covers the event with news, a video of attendees, and the final keynote.

MySQL:

Sheeri Cabral shares how she determines MySQL fragmentation.

Baron Schwartz posts the third in a series of posts on MySQL limitations – one thread per connection. In case you missed them, part 1 covered single-threaded replication, part 2, the binary log, and part 3, subqueries.

SQL Server:

On In Recovery, Paul S. Randal invites readers to participate in a survey to determine wait times on systems. Chime in with your feedback by commenting on his blog post or sending him an email after reading the instructions. Paul is also calling for participants for T-SQL Tuesday #12 – Why are DBA skills necessary.

And lastly in Postgres news, PG West 2010 is happening next week. There are a number of posts on the need for replication in PostgreSQL 9.0. Joshua Drake stirred the pot, responded and created a Replication poll to find out what you really think. Cast your vote!

Happy Haunting weekend.

The 5 hour flight to San Francisco for OpenWorld is a good chance to catch up on some blogging I’ve been meaning to do. Now if only Air Canada would get some in-flight Internet (they ran a trial last year an shut it down without comment in April)

With the release of the 11.2.0.2 patchset, Oracle has stopped releasing sets of individual patches, but instead is packaging it as a self-contained, complete software install. I can see many benefits to this method, and quite frankly am wondering why it took so long to come about:
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There was a discussion on the OTN General database forum, in which the OP asked creating a table with just one row and restricting that table to just one row. Here is my attempt at it.

I created a table with two columns, and the second column is a virtual column and contains a constant. I created a unique index on this column. On every insertion, this second column always evaluates to 1, and unique index (which become the function based index on virtual column) ensures that only one row remains in the table.

oracle@test # sqlplus /nolog
 
SQL*Plus: Release 11.1.0.7.0
 - Production on Sat Aug 28 19:09:16 2010
 
Copyright (c) 1982, 2008, Oracle.  All rights reserved.
 
idle> conn test/test
Connected.
test@test> create table t1
 (c1 number, c2 generated always as (1) virtual);
 
Table created.
 
test@test> create unique index idx1 on t1(c2);
 
Index created.
 
test@test> insert into t1(c1) values (1);
 
1 row created.
 
test@test> commit;
 
Commit complete.
 
test@test> insert into t1(c1) values (1);
insert into t1(c1) values (1)
*
ERROR at line 1:
ORA-00001: unique constraint (TEST.IDX1) violated
 
 
test@test> insert into t1(c1) values (2);
insert into t1(c1) values (2)
*
ERROR at line 1:
ORA-00001: unique constraint (TEST.IDX1) violated