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UnConference - Jonathan Lewis

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Oracle Closed World and Unconference Presentations

There are so many things to blog about these past few days. That is mainly about the cool stuffs around OCW and OOW, sessions that I have attended (OCW, unconference, OOW), plus the interesting people that I’ve met on various areas of expertise.. So I’ll be posting some highlights (and a lot of photos) on the next posts.

Last Monday (Sept. 20) I was able to present at the Oracle Closed World @ Thirsty Bear. The full agenda is here

HOWTO: Handle Complex XML Schemas (Part 1)

Currently sitting in at the Oracle Open World 2010 presentation of Sam Iducula, Consulting member of the tech. staff and Mark Drake, Sr. Product Manager for Oracle XML DB. Before getting into the more in-depth topics Sam explained XML schema usage, for validation via XML schema validators like for example XML Spy or JDeveloper. This is currently really needed because those more used XML Schema like the really big ones out there like H7, etc, are nowadays so very very big that a good XML Schema validator is really needed. XML Schema in binary XML format is stored in a post parsed binary format. This has the advantage that Oracle knows about the format when storing the XML document. Extra information can be shared by the database by registering the XML Schema in the database that validates the Binary XML content.

There can be a lot of recursive dependencies, via the import or include references in a XML Schema, which make it even more difficult to make optimal use of this information. For example in the H7 (Health Level 7 schemas) setup this includes over 100 included XML Schemas. Oracle 11gR2 has been greatly improved performance and handling of those very huge meta data information as stored in such XML Schemas. Via streaming schema validation and adding hints via xdb:annotations, this provides the database with even more information on how to optimal handle these structures and as such performance can be improved even more. Some of those hints could be used to avoid the creation of objects, in this case while using XMLType Object Relational storage via, for instance, xdb:defaultTable=”" (providing an empty string) or store parts of the XML document information out of line. By the way for this last example you should use JDeveloper because it will annotate the XML Schema incorrectly (the bug has been reported by me). One of the improvements in is huge improvements were made in cycle detection recognition, so they are handled even better in the mentioned version.

On the XMLDB home page on the Oracle OTN website a package of tools provided (“Oracle XML DB Ease of Use Tools for Structured Storage“) which can make your life easier regarding those xdb:annotation’s especially for those enormous big XML Schemas. This tool set which enables you to automate a lot of hints in XML Schema optimization you would like to make. Via XQuery or other XML DB update statements you are also able to override the by the database generated naming or storage options. Via some simple anonymous PL/SQL blocks this can be very easily done via for example, DBMS_ANNOTATE-x packages contained in this XML tool set, as said which is freely available on the XML DB OTN Oracle website.

Automation of xdb:annotations
Click the picture to enlarge

This tool set also comes with a white paper that shows and demonstrates some of the best XML handling ideas and experience gathered trough a lot of years handling customer use cases the Oracle XML DB Development team had. For example if you know it’s not applicable to your XML document you are able to switch off or alter DOM validation handling while storing or handling your XML document in the database. You can override ordering for example if it is applicable for your XML Schema, this avoids oracle checking it, which improves handling, but, be very aware, it can also be dangerous doing this if it was implemented by the person who created the XML Schema, but just didn’t care about the real life implement and/or it’s importance regarding being a actual mandatory requirement in practice.

I have experience multiple times that even with official XML Schemas the restrictions didn’t match real life use, so although automation really helps you to manage your XML registered schemas more easily, you must be aware of those exceptions. XML schemas can be created very loosely on real life implementations which can get you in a lot of problems after these storage models, based on such an XML schema, is used in your database design; those rules will be enforced via a XML schemas in the database.

As always, proper design with future needs in mind, takes time to do it properly. This is also the case regarding creating a good XML schema.

In Oracle 11you have now the possibility, via this tool set, to use DBMS_XML_MANAGE (for XMLType Object Relational storage) to rewrite table to column mapping, which figures out for you, makes it more easy, to identify and create supporting indexes on ComplexTypes. This has the advantage that you can create indexes with some more meaningful names like, for example “line_items_uniq_idx_01″ or whatever the naming convention within your company might be.

In the latest XDB toolset there will be now also a XDB_ANALYZE_XMLSCHEMA package which sorts out all of the scripting and possible options, while you feed it the actual XML Schemas. As was demonstrated by Mark Drake, all the FpML schemas which have a lot of dependencies of each other where analyzed, annotated, registered and it created over 100 tables and more than 2500+ objects in minutes. Try doing this by hand…

Also while using this package it will sort out the proper XML Schema dependencies and in which order all those XML schemas have to be registered in the correct order (based on includes, imports and ref’s used by Simple- and ComplexTypes). Sometimes you have to break up column create table statements because the maximum amount of columns allowed by Oracle in one single CREATE TABLE statement is “only” 1000 columns. This package will help you figure out how much of those Object Relational storage items will have to be moved “out of line” and/or to break up on a certain level in the XML hierarchy of the XML tree to avoid this 1000 column limitation but also to provide the design info needed to get the maximum performance.

This tool set used for XMLType Object Relational storage is only useful if you XML design is highly relational. If not then, your XMLType storage module should be based on Binary XML. The advantage of using XMLType Object Relational storage is that you make full use of Oracle relational technology and optimizations, which is available since a long long time and full use of, for example, the Cost Based Optimizer will kick into effect. On the other hand, be aware if your XML design is really relational, maybe you should have created it by relational means. There should be a proper use case to work with the XML format in the first place. My adagio always is: if it is not XML, don’t use Oracle XMLDB. If it is, go for Oracle XMLDB, if not only that is a “no cost option” within your Oracle database and it has been designed, since version, to optimal handle XML in your database.

For further information about choosing the proper XMLType storage model and how to optimally query these structures, have a look at:



Oracle OpenWorld 2010 Day 1 Highlights

  Well Oracle OpenWorld 2010 has finally arrived. The first thing I’ve noticed is just how many more people appear to be around at the conference this year compared to last. Better economic times and the addition of the JavaOne component have certainly made a difference. Here’s a piece of advice. Don’t go out drinking lots [...]

Oracle Open World 2010… Optimizing Oracle Databases on Sun SPARC Enterprise M-Series Servers

This year at OOW I will be co-presenting on Oracle performance on Sun servers. Stop by and say hi if you get a chance.

ID#: S315915
Title: Optimizing Oracle Databases on Sun SPARC Enterprise M-Series Servers
Track: Sun SPARC Servers
Date: 20-SEP-10
Time: 12:30 – 13:30
Venue: Moscone South
Room: Rm 270

MOTS Mini – Nasty weather, for absent friends


Is it a blog, plog, phlog, I don’t know but hereby trying out the WordPress Android app. to see if this works regarding more lasting fast tweet-like updates. The start to this “conference series” for MOTS and OOW was wet; really horrible weather above Holland and me, making a mistake interpreting 12.45 pm, didn’t make it any better. But he, no stress, right?

My flight with delta airlines boarded almost 2 hours before departure which wasn’t also fun at all, but you learn to get by. One big coffee, sandwiches and a “Nicotinel” gum makes life easier. Would they also have a gum for Whiskey addictives…


Anyway. Ann Arbor here I come.

OOW10 Bloggers Meetup Agenda — T-shirts are Back and More…

Almost time for the Annual Bloggers Meetup @ OOWCounting down. The details are finally organized — this year, we have not one, but TWO great prizes at the Oracle OpenWorld Bloggers Meetup.

1) T-shirt art contest on stylish Pythian designer t-shirts — one lucky blogger will receive an HP X310 Data Vault, generously sponsored again this year by HP.

2) For the best, most creative blog post about the meetup itself, Pythian is giving away an Apple TV. But, there are a few small rules:

  1. the blog post must use as many names of people in attendance as possible.
  2. the blog post must be readable. It needs to make sense to someone who wasn’t there. It must be a story and not a list.
  3. the blog post must contain one other small tidbit of information about each individual that you’ll uncover during your “networking” as you weave your fascinating stories of the evening (like their blog name, a contact detail, favorite color, title, hobby, cat’s name, certification, what they were drinking, how much they had to drink…).
  4. the entry must be posted by midnight on Sunday the 26th of September. Please reference this post in your blog and it should be automatically picked up by the blog engine and posted in the comment as a track-back (if it doesn’t appear in the comments for some reason — please do post the link in your comment!

Can you tell we’re trying to encourage a little more mingling? :)

And last but not least — all this couldn’t be happening without Vanessa Simmons who’s been orchestrating all of the fun this year. Thanks Vanessa!

HP X300 Data Vault appletv

OOW 2010 – my schedule

I was able to finalize my schedule a week before the OOW 2010 and most of the sessions that I’ll be attending are related to Performance & Exadata.

So that would be:

XMLDB Oracle Open World Agenda…

Becoming a bit of a tradition actually…

Trying for others to avoid the same, at least it was in 2008/2009, ordeal going thru the O.O.W. Schedule / Content builder trying to find XMLDB topics, I listed those I could find on the XMLDB OTN Forum. As said, trying to follow up on a tradition and to get myself (and hopefully you) an overview on things to come during Oracle Open World 2010 (/Oracle Develop /JavaOne). This year I think its becoming BIG regarding amounts /attendance of people if not only due to the combination of O.O.W./Develop/JavaOne on the same spot in San Francisco…

So, for me and those who are interested, just like the year before, hereby an attempt to find all XMLDB related presentations, workshops and other events during Oracle Open World 2010. I will try to add info, time and days later on (and/or you might) if I find them and/or if they become known. See for XMLDB presentations and Hands-on Lab sessions here:

I hope you enjoy your presentations during O.O.W. and who knows we meet this year.

Not really into XMLDB presentations? Have a look at the 50+ Oracle ACE(D) presentations Oracle Open World and JavaOne, Oracle Develop listing here

Oracle OpenWorld 2010 Agenda (Breakfast In America)

I was all set and ready to go Oracle OpenWorld this year when things took a turn for the worse and it looked very much as if I wouldn’t be able to make it but things have thankfully changed yet again and it now looks like I will finally be able to make it to OOW this [...]