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Web Cache Compression and MOD_GZIP

Duncan Mein - Fri, 2008-09-26 04:07
Some of my colleagues are working on a project where bandwidth is massively limited (64k). One suggestion to increase application response time was to use MOD_GZIP (an open source compressor extension to Apache) to compress the outbound HTTP traffic. The only drawback is that MOD_GZIP is not supported by Oracle.

Since we are using Oracle Application Server, Web Cache achieves exactly the same by simply adding a compression rule to Web Cache for the URL Regular Expression /pls/apex/.*$

We noticed that without any compression of the HTTP outbound traffic, our test page took 30 seconds to fully render on a 64k link. Turning on compression reduced the rendering time to 7 seconds. Very impressive.

Navigating through an application with compression turned on was noticeably quicker than one without compression.

To test if your outbound HTTP traffic is compressed, I would grab the Live HTTP Headers extension to Firefox and you are looking for a line like: Content-Encoding: gzip in the outbound response.

I configured both APEX and Discoverer Viewer to use compression by following the metalink article: 452837.1

Data Modeling with SQL Developer

Jared Still - Fri, 2008-09-26 00:33
Unlike Open World 2007 there were many database oriented sessions at Oracle Open World 2008. There were many good performance oriented sessions, so many in fact that there were several conflicts in the schedule, and I had to pick one in several time slots that had multiple choices.

One of the more interesting sessions (for me anyway) at OOW 2008 was a session not on database performance, but on data modeling.

The SQL Developer team has been hard at working creating a data modeling plugin for SQL Developer.

This appears to be a very full featured tool, and appears to be the answer to the question "What will replace Oracle Designer?"

While Designer is much more than a data modeling tool, that is one of the core features of the tool, and many folks have used it just for its data modeling capabilities.

The new ERD tool is no lightweight, it is quite full featured from a database modeling and design standpoint.

Some of the features included:
  • Domains generated from data
  • Real logical and physical modeling, not just one model with 2 different names.
  • The ability to reverse engineer several schemas at once and have them appear not only as a master model, but each individually as a sub model.
  • Sub model views may be created on sets of objects as well.
  • The tool can determine all tables related to a table through FKs and create a sub model based on that set.
  • Two forms of notation: Barker and IE
  • Many options for displaying sub/super types (D2k fans rejoice!)
  • Glossary - a predefined set of names. These can be used to enforce naming conventions for entities, tables and relations.
  • Schema comparison with DDL change generation
Also of note, in addition to Oracle schemas can be imported from SQL Server, DB2, or any ODBC connected database.

The repository can be either file based, or database based.
There are two versions of the tool, a plugin to SQL Developer, and a stand alone version. The stand alone version will use only the file based repository.

Now for the bad news.

The release date has not been established. The only release information given was 'sometime in the 2009 calendar year'. As the database repository has not yet been designed, the long time to release is understandable.

And finally, licensing has not been established. It might be free, it might not. If not, at least we can hope for reasonably priced. Personally I thinking having a decent data modeling tool that comes free of charge with SQL Developer would contribute to higher quality databases, as more people would use a real database designer rather than a drawing tool.

There was probably more that didn't make it into my notes.
Suffice it to say this is a great development for data modelers and database designers.

Following a few screen shots taken during the presentation.

Categories: DBA Blogs

A lazy log writer

Claudia Zeiler - Fri, 2008-09-26 00:11
I've been laughing because I live 1 block from Moscone Center. It was closer for me to walk between the conference and my house than it was to walk between some of the sessions. Today, I saw the other side of that coin. I got ordered back to work and missed the last day of the conference, (and Chen Shapira's presentation!!!)

What was going on at work? Not much - as in not what should have been. I like looking at the performance monitor on Enterprise Manager for a quick glance at what is going on. It wasn't a pretty picture.

Clicking on the 'Blocking Sessions' tab I saw that that the log writer session was blocking various other sessions.

I went into the alert log and was pointed to a log writer trace file. Inside the trace file I found

*** 2008-09-25 15:28:24.239
Warning: log write time 15460ms, size 6999KB

*** 2008-09-25 15:28:24.836
Warning: log write time 590ms, size 6898KB

*** 2008-09-25 15:28:29.852
Warning: log write time 5020ms, size 6999KB

I looked at metalink and got

" The above warning messages has been introduced in patchset. This warning message will be generated only if the log write time is more than 500 ms and it will be written to the lgwr trace file .

"These messages are very much expected in database in case the log write is more than 500 ms. This is a warning which means that the write process is not as fast as it intented to be . So probably you need to check if the disk is slow or not or for any potential OS causes. "

We just upgraded to Our storage is across the great divide at another company. We are often short of answers other than, "Everything is configured correctly". With quite a bit of work we have gotten a pair of LUNS allocated for redo logs.

As a test, I moved the redo logs from the SAN to a NSF drive - NOT one that should be allocated to redo. Here was the immediate result:

The log writer waits stopped. Compliments from management. A request from management to storage management to move the entire database to this kind of storage, everyone is happy


Tonight I looked at the trace file:

*** 2008-09-25 22:53:34.154
Warning: log write time 750ms, size 0KB
*** 2008-09-25 22:53:35.943
Warning: log write time 1770ms, size 28KB
*** 2008-09-25 22:53:39.889
Warning: log write time 940ms, size 0KB

Log writer is taking forever, and it isn't even doing anything!

To be continued..... and detective suggestions welcome!

OOW2008 day 5 – It’s A Wrap

Pawel Barut - Thu, 2008-09-25 23:52
Written by Paweł Barut
Before I start to summarize my Day 5 at Oracle OpenWorld, I would like to add few words to day 4 (Wednesday).

Managing Very, Very Large XML Documents with Oracle XML Database
It was very good session. It one of those where practical experience was shared. Presenters showed step by step how to load very large XML files to DB:
  • Setting up XML schema
  • Schema annotation technique and few directives
  • Direct Insert Store for XML
  • Differences with loading XML into XML DB in 10.2g and 11g

The Appreciation Event.
It was very nice concert on Treasure Island. I’ve especially liked Seal. Beside that there was lot of good food and drinks.

Day 5

I will start with session Oracle’s New Database Accelerator: Query Processing Revolutionized. As I’ve expected it was related to announcement made yesterday. My yesterday’s description was not perfect. Now I will try to fix this. First of all we have 2 new machines. But one them is included in the second one.
Oracle Exodata Storage Server - it is hardware from HP: 2 Intel quad-core processors, 12 disks (300GB, 15RPM or 750 GB, 10 RPM) with disk controller optimized for best bandwidth and 2 InfiniBand connectors to connect to external equipment. The code for this product is HP DL180G5 (at least that was on one of slides). This computer is sold with preinstalled Oracle Enterprise Linux 5.1. The main role of this machine is to store database files. It cannot be used to store normal files.
The second hardware is HP-Oracle Exodata DB Machine - This one is rack box equipped with 14 Oracle Exodata Storage Servers and 8 DB Servers each with 8 Intel processors. On those DB Server runs Oracle Enterprise Linux 5.1 and Oracle RDBMS 11g ( Even more – 6 such DB Machines can be connected into cluster.
Where is the revolution? In the way Oracle DB communicates with storage. There is new protocol iDB that allows to push query predicated down to storage. With this, number of data transferred from Storage to DB Server is minimized. This feature is called Smart Scan. It can be leveraged only when full table (or partition) scans occurs. And it still keeps all read consistency.
And here is technical spec from Oracle.

And short on my other sessions: Oracle Database Performance on Flash Drives
Very interesting session showing results of different approaches for using Flash drives. As an conclusion there was presented formula, when Flash drives can help with performance, and when it is better to stay with fast rotating drives, and when even with low cost but high capacity drives. As an side note when we consider power usage, Flash drives can be even more economic then traditional rotating drives.

Oracle ACE Director: Birds-of-a-Feather Tips and Techniques
Session lead by Oracle ACE’s: Lewis Cunningan, Arup Nunda, Edie Awad, Mark Rittman, Tim Hall, Hans Forbich and Bradley Brown. The session was Q&A style. ACE’s were answering questions based on own experience, and that is sometimes different that Oracle’s official recommendation.

Real-World XML DB Examples from Oracle Support
This was rather chaotic session, and did not gave me useful information- IHMO waste of time.

And the last session by Tom Kyte Reorganizing Objects
Tom have done great job showing different myths about when DBA’s should reorganize tables and indexes. It was really Great speech. Might be there was too much material for an 1h session, and everything was shown little bit in an hurry.

The day has ended with small party It’s A WRAP
While writing this I’m sitting in hotel and watching Fireworks over the San Francisco Port. Tomorrow I’m leaving San Francisco for 18h trip back to home.

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Categories: Development

OpenWorld unconference presentation about Rails on Oracle

Raimonds Simanovskis - Thu, 2008-09-25 16:00

On last day of Oracle OpenWorld I did my unconference presentation – Using Ruby on Rails with legacy Oracle databases.

As I did not know if anyone will come to listen to it I was glad that six people attended (including Kuassi Mensah from Oracle who is helping to promote Ruby support inside Oracle). And on the previous day I also managed to show parts of my presentation to Rich and Anthony from Oracle AppsLab team.

I published my slides on Slideshare:

And I published my demo project on GitHub:


Thanks to all Oracle people who recognize my work on Ruby and Oracle integration and I hope that our common activities will increase number of Ruby and Rails projects on Oracle :)

Categories: Development

Oracle Open World 2008 Podcast

Mark A. Williams - Thu, 2008-09-25 14:45
I've never really been a prolific blogger and the "interruption" of OOW 2008 has definitely impacted this. However, my podcast with Tom Haunert of Oracle Magazine is now available at the following location:

Oracle Magazine Feature Casts

The title of the podcast is:

Origins of a .NET Developer

Exadata - has it been in development for two years?

Nigel Thomas - Thu, 2008-09-25 14:09
Just my nit-picking mind, but why does the Exadata technical white paper say (at the time of writing at least) that it is "Copyright © 2006, Oracle"? I don't think they've been working on it that long - much more likely some soon-to-be-embarrassed technical writer has cut and paste the standard boilerplate from an out of date source.

What, no rule-driven content management?

Exadata and the Database Machine - the Oracle "kilopod"

Nigel Thomas - Thu, 2008-09-25 14:09
There has already been plenty of interesting posts about Oracle Exadata - notably of course from Kevin Closson here and here (update: and this analysis from Christo Kutrovsky)- but I just have one thing to say.

Larry Ellison was quoted in a number of reports saying the Oracle Database Machine "is 1,400 times larger than Apple’s largest iPod".

Larry, when you want to get over that something is big - really big that is, industrial scale even - just don't compare it with a (however wonderful) consumer toy. Not even with 1,400 of them. 1.4 kilopods is so not a useful measure.

By the way, can I trademark the word kilopod please? (presumably not - a quick google found a 2005 article using the same word, and there is some kind of science-in-society blog at kilopod.com).

OOW2008 day 4 – HP-Oracle Exadata Server Announcement = Extreme Performance

Pawel Barut - Wed, 2008-09-24 18:25
Written by Paweł Barut
Today is very busy day for me. It’s just after Larry Ellison keynote on which first Oracle Hardware was presented. I’m a little big skeptic if Oracle is realy going for hardware business. It is rather that Oracle had great idea how to solve problems with really big databases and growing demand for storage, and joined forces with HP to create new quality in data processing. So, how it looks: in one box we have 2 intel 4 core processors and 12 disks as storage – it is called The Exadata Programmable Storage Server. This machine is not storage, and is not pure DB Server as well. It can process queries (so it is DB), and it stores Data (so it is Storage). But it needs separate DB Server to work at full performance. How it works: DB Servers receives request for data. It then retries data from Exadata Storage Server, but data get initially filtered, so number of data transferred from Storage Server to DB Server is reduced. It allows much better overall performance.
At least this is my understanding. I will go also to DemoGround to get direct look at this machine, and more detailed specification.

Today I’ve also participated in few sessions.
Soup-to-Nuts RAD Development Using Oracle SQL Developer and Oracle Application Express It was quick show how to create simple application using APEX and SQL Developer. It focused on modeling capabilities of SQL Dev, and integration between APEX and SQL Dev. It was shown, how to view APEX objects in SQL Dev, and how to leverage this integration. There was also presentation of new functionality in APEX to migrate Oracle Forms to APEX.

Agile Database Testing Techniques (IOUG) This was very interesting session giving practical inside on how to organize unit tests in DB, how to validate that upgrade scripts run successfully, and how to prepare DB environment for Daily Builds. Presenter shared his real world experience and this was the biggest value of this session.

SQL Tuning Roundtable with the Experts This one was rather boring, as topics and answers were almost exactly the same as on session “Inside Oracle Database 11g Optimizer: Removing the Mystery” that I was participating yesterday.

Now I’m sitting in OCP Louge, and in few minutes I’m going for last session Managing Very, Very Large XML Documents with Oracle XML Database and then for The Appreciation Event.


BTW. This is my post # 100.
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Categories: Development

My OpenWorld 2008: 23 Set

Oracle Apex Notebook - Wed, 2008-09-24 14:27
The first session of the day was schedule to 11:30 AM. I had some free time that I used to get around and see what was happening. I went to Moscone North and after blogging a bit on the couches, went to the Unconference section and then the bookstore. I couldn’t find John Scott’s Pro Oracle APEX book, but later at night he told me that the book was there, so maybe I’ll go to the bookstore
Categories: Development

My Mentor is an Oracle Certified Master in Oracle 10g now!

Sabdar Syed - Wed, 2008-09-24 05:01

Dear All,

I’m pleased to say that my elder brother, Mr. Syed Jaffar Hussain, is an Oracle Certified Master in Oracle 10g now. He is truly deserved for it. In addition to this, he is already an Oracle Certified Professional in multiple tracks such as Oracle 10g/9i/8i, RAC DBA Expert, and also an Oracle ACE Award winner.

He is my mentor and motivator. So, I will have to gear up for Oracle Certified Master Program, and get trained under his guidance for the same.

Sabdar Syed,

OOW2008 day 3

Pawel Barut - Tue, 2008-09-23 23:08
Written by Paweł Barut
This day was quite good for me. I’ve finally overcome problems with jet-lag.

I’ve started day on session “Inside Oracle Database 11g Optimizer: Removing the Mystery”. It was very good session explaining how new features in optimizer works. It provided inside on Plan Profiles, improved bind variable picking, improved performance for statistics collection and new statistics for correlated columns.

My next session was not exactly what I was expecting. “Global-Scale Web 2.0 Data Platforms: Sharding with Oracle Database”. I was expecting technical inside, but it mostly was marketing speech on “why Oracle is better then MySQL”. Break between sessions I’ve used to ride on Cable Car:

I’ve ended day on session “Top 10 Things You Wanted to know about ASM”. As I were not using ASM yet, it was good overview of features, and best practices for using ASM. Now, I’m going to rest to be prepared for next day, and big keynote by Larry Ellison.

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Categories: Development

Some positive drag-and-drop experience

Raimonds Simanovskis - Tue, 2008-09-23 16:00

In the previous post I wrote that I didn’t quite like drag-and-drop development style in JDeveloper that I experienced during Oracle OpenWorld hands-on session.


Today I was in Oracle BI Answers & Dashboard hands-on session and during this session I was also drag-and-dropping to create reports, charts and business intelligence dashboards. But in this case I liked it as it seemed natural way how to create such reports.

The main difference why I liked it was that I got immediate feedback how the end report will look like – after each change I could immediately see and test real report with real data. And such immediate feedback is key prerequisite for interactive analytical reporting development.

In JDeveloper case I needed to compile and build everything and restart local application server after each change to see real results from any change – and it took at least 10 seconds for just sample “hello world” application. I assume that this lag will be even longer in larger real projects. Probably it is not so long time but when you compare it to 1 second feedback time then anything larger seems long.

I also visited Oracle demo grounds where I discussed my concerns regarding JDeveloper drag-and-drop development style. At the end we reached common understanding that JDeveloper and ADF framework is really good for former Oracle Forms developers who do not want to learn HTML, CSS and Javascript and auto-generated applications could be quite OK for internal enterprise applications. But if you want to build advanced web applications you still need to learn and be expert in these web technologies (HTML, CSS and Javascript).

Categories: Development

My OpenWorld 2008: 22 Set

Oracle Apex Notebook - Tue, 2008-09-23 12:01
Today I have changed my agenda and attended two sessions that weren’t initially in my schedule. The first was the one presented by Dimitri Gielis about working charts in APEX and the second one was about mashups and integration with APEX by Simon Boorsma. Before that I went to Moscone North to watch a bit of the keynote. You can’t believe the number of people that were there! The following
Categories: Development

OOW2008 day 2 – Oracle Beehive

Pawel Barut - Tue, 2008-09-23 10:23
Written by Paweł Barut
This day started with Keynote presented by Oracle President Charles Phillips. He spoke about Oracle acquisitions, and more complete portfolio of products that Oracle have now. What caught my attention most was announcement of new product, new collaboration platform Oracle Beehive. It joins features of email, calendar, document sharing, web conference and few more in one suite. What is most important those tools are open, so user can use ex. MS Outlook to access mails or calendar entries. Security is one of the key features. When you share document with others, they can see document in theirs workspace. They can even make local copy of this document. When document is deleted by original author, then all copies of the document become unusable for anyone. This is because all shared documents are encrypted and signed. While opening document there is validation of access rights for document. For me it seems as this is based on technology acquired from Stallent. It seems that this product will try to get market from MS Sharepoint and IBM Lotus.

Today I took some time to see Exhibition Hall, and walk around the city. While walking I’ve found one interesting bus – I was Bus that was advertising Microsoft SQLServer:

It looks pretty old :). Microsoft does not want to be absent in San Francisco during Oracle’s big conference.

I’ve also participated in few session on SOA (Service Oriented Architecture) and AIA (Applications Integration Architecture). Basically I wanted to have better understanding of Oracle offering in SOA area.


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Categories: Development

OOW - Day 2 - Simple things

Claudia Zeiler - Tue, 2008-09-23 00:49
I spent most of the day in hands on classes. I learned to use the Configuration Management Pack of Grid Control to install patches. It looked really interesting. Now I have to go back to work and figure out how to install Grid Control so I can use it. I assume there will be a fair amount of kicking, screaming, and tearing out my hair in that little task which the Oracle demonstrator waved his hand at, as if to say, "It's nothing". Oh those little nothings.

I then went to a hands on on
Oracle Advanced Compression in 11g. The class really was just working through a couple of OBE examples with the comfort of people who actually know the a LOT about Oracle Compression there to help with the silly little problems that people have working through examples. I wish I had had some sort of deep questions to ask about compression. All I learned was, it works. There is some time, and some space savings. It will be useful when we move up to 11g.

When I say that the Advanced Compression was 'Hands On', I mean it literally. Braille would have been more accurate. For some reason, the whole demo was available in a box slightly larger than a youtube video. I get annoyed with myself when I have difficulties with the parts that I think should be the simple parts.. Here were a whole group of Oracle employee experts who couldn't make the VM window expand to the whole screen. There was more compression in the demo than anyone intended!

Metalink is now My Oracle Support!

Sabdar Syed - Mon, 2008-09-22 05:21
Yesterday, when I logged in to Oracle Metalink, I saw a new look of Metalink, and also Oracle Metalink Support has now been renamed to

As per My Oracle Support:

“Introducing My Oracle Support, the next generation MetaLink experience. My Oracle Support offers you secure, real-time access to Oracle experts on the complete Oracle software stack. It also provides groundbreaking personalized & proactive support capabilities that help reduce unplanned down time and improve system stability. Leverage the Internet for immediate access to 24/7 support and get the critical and timely information you need for running your usiness.”
A new look of My Oracle Support

Important Blog on new look of My Oracle Support.

Introducing... My Oracle Support!

Classic MetaLink vs. New MetaLink — What’s the Difference?

Sabdar Syed,

How to make a Link to be opened in a New Browser Window?

Sabdar Syed - Mon, 2008-09-22 03:03
It's as easy as follows:

To get a link or URL, you specified or referred in your blogs, to be opened in a separate New Browser Window, what you need to do is add the target="_blank" attribute to your link tag i.e. in in the HTML code.

For Example:

  &lta href="http://sabdarsyed.blogspot.com/" target="_blank"&gt  This is My BlogSpot!&lt/a&gt
This will give you the following link:

This is My BlogSpot!

This is useful when you do not want to open a link, you specified or referred in your blog, to open in the same window, rather it should open in a new browser window, by keeping original post open.

Sabdar Syed,

OOW - Day 1 - Blogger's perks.

Claudia Zeiler - Mon, 2008-09-22 01:05
OOW'08 - Day 1. I spent the day in the 11g New Features Exam Cram. A couple of people encouraged me to try the exam. I have never touched 11g. I took the course as an intro to 11g, not as a refresher before the exam. If I passed the certification after just this, then the OCP really is meaningless. I prefer to actually know what I'm being tested on when taking an exam.

I happened to be seated next to
, who apparently does work with Oracle 11g and is ready for the exam. I wish him all the best on the exam.

Fuad's conference badge had a large 'Blogger' written in bright orange on the case. I know that I signed up for one. I asked at the registration desk, and they gave me a 'Blogger' badge too. I lined up for the Keynote Address. Immediately, the ushers pushed me out of the main line and into a smaller line for press & bloggers. I was led to a special area of the auditiorium saved for bloggers - a long table set up so that we could record every golden world of Mary Matalin & James Carville. For Pete's sake! I think this 'Blogger' badge is going to have some strange side effects.

Then this evening I was able to get together with all of the other Oracle Bloggers who I have been following for a year. That was really special. What a nice bunch of people!

Arriving San Francisco – OOW2008 day 1.

Pawel Barut - Sun, 2008-09-21 19:41
Written by Paweł Barut
My trip to San Francisco went well. No delays, no problems with flight reservation – see what happened to Tim. I had small problems with hotel reservation, but finally everything is fine – I’m in different hotel then I’ve reserved. I’m suffering little from jet-lag. I slept an hour or two in plane, and then I could not sleep during night. So I feel little tired. The weather in SF is great, especially when comparing to very cold and rainy weather in Krakow last week.

My first experience of San Fracinsco is not very good. Seems to be not very friendly, and is definitely not of my style. I might change my mind when see more places in SF. But Oracle Conference is organized very well, so my attitude is improving :).

For today, I’ve planned mostly session regarding Security and Identity management. First of those session “Oracle Security Risk” was very good. Especially speaker Tanya Baccam from SANS.org was impressive. Presentation was about common problems with security in web based and forms application that use Oracle DB as backend. One type of attack was new to me: CSRF – Cross Site Request Forgery.

Next one was Security Roundtable – lot of questions from audience on variety of topics. Most hot one: applying CPU patches, Auditing, DB Valut, Encrypting data and transmissions.

Then was Oracle Identity Management lead by Matt Topper. Good overview of identity products from Oracle stack.

My last one session “Storage: A New Paradigm for Database” was also very good session. Ari Kaplan show now storage solutions can improve Backup/Restore times for database and decrease demand for storage space. He also presented new RAID-DP concept, and claims that it can provide better performance, with lower storage demand, and provide higher availability. This is something that I need to investigate in more details.

For the evening I’m going to take part in Bloggers Meetup.

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Categories: Development


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