Exadata - has it been in development for two years?

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long - much more likely some soon-to-be-embarrassed technical writer has cut and paste the standard boilerplate from an out of date source.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"

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).

Back to the future - or is that forward to the past

I'm starting a new contract this coming Monday. I'd better keep the client confidential until I've found out how they feel about blogs, but the job revolves around data matching and data quality, using Oracle and SSA.

At the interview, I found myself less than 100m from the site of my first ever "proper" job (the old Scicon offices are now an upmarket West End hotel). So just 28 years and 1 month later, I will be sauntering along Oxford Street once again.

I'll be commuting daily at first, but I will try to stay down during the week at least some of the time if I can find somewhere cheap, clean and convenient. Any old colleagues around central London - sometime between now and Christmas we should meet up ...

Microsoft acquires DATAllegro

Lots of interesting posts on this news, from:

• Curt Monash's DBMS2 blog - all his DATAllegro links are here - as there are so many of them. He also links to other comments
  
• Philip Howard at Bloor and IT-Director suggests that MS is assembling an entire DW stack with Zoomix and perhaps one day Kalido and Ab Initio as additional components
• Mark Madsen from Intelligent Enterprise says what it means for customers, other vendors and BI
  
• Kevin Closson with his welcome plain-speaking (and Oracle-centric) viewpoint refers back to earlier posts wondering about some specific details of this emperor's clothes
  
• Seth Grimes thinks it's a mistake that will be slow to deliver (and may hurt existing DATAllegro customers); it should have been Dataupia
• DATAllegro CEO Stuart Frost sounds happy with his new role
  

Meanwhile Seth Grimes also uses the news to point up a real difference in quality between Google and Microsoft search capabilities.

ESB consolidation - Progress buys Iona

I guess Iona was one of the first well known Irish software companies, and now it must be one of the last. It has succumbed to Progress Software for $106M. Paul Freemantle beat me to the news that Progress now owns or is a major committer for at least 4 different ESBs - Sonic, Artix, C24 and ActiveMQ/Camel/ServiceMix (plus Actional if you like) - hey, that's more than Oracle isn't it? (or maybe not...).

First come first severed (sic)

A little off topic perhaps, but sometimes the illiteracy of business communications just amazes me. This is from a Jobserve recruitment ad:

• A large railway company are looking to hire a Oracle Developer to join there expanding company on a 3 month rolling contract.

Next comes a fairly detailed set of technical requirements; as it seems to make sense, it was no doubt supplied by the said railway company. Finally the ad ends with this appeal:

• The is major role and candidates will be selected on matching skills and on first come first severed basis

Sounds painful! Seems unfair to be severed for being the first response. Perhaps I should wait a week before applying?

Vote now to open up Metalink!

Richard Harding has proposed on Oracle Mix that Metalink should be opened up:

There is goldmine of useful information in Metalink and having access to it would optimize the efficiency of people using Oracle toolsets, in my opinion enhancing productivity and by inference Oracle adoption globally which would be win win for everyone.

I've expressed the same thoughts myself in the past. So all of you Oracle professionals who would benefit from access to Metalink but are not included in your employer's arrangements (especially for freelancers like me) - go and vote!

Another blogger

Good to see Mark Bobak blogging - he's one of the stronger contributors to the Oracle-L mail list. Thanks to Doug Burns for spotting his blog.

BEA Aqualogic broken up

The Register reports on how Oracle is going about the integration / breakup of BEA's Aqualogic SOA products (splitting them between ex-Stellent and Oracle Fusion product lines). Oracle's actions are described as "firm but fair".

Performance problems concatenating LOBs

Greg Pike talks about some potential performance pitfalls with LOBs; I would comment on his blog, but it's a login only. Anyway, I posted on these problems last year (specifically with DBMS_LOB.APPEND), and posted some code to deal with it. Batching up appends makes a big difference - a 15-20 fold improvement, in the example shown (against 9.2.0.5).

MS subpoenas Oracle in Juxtacomm ETL patent case

Vincent McBurney summarises the latest developments in the Juxtacomm "we invented ETL, yeah really, give us all your money" patent case, which I have mentioned before. Dang, don't these "obvious" cases take a lot of time and effort to clear up.

Latrz - for all those web pages you want to read, just not right now

James Strachan blogged about Latrz here. It's a neat little Google app that lets you bookmark and tag pages you want to read later, then come back and read them (and check them off your list) when you've got a spare few minutes. Coming soon, you'll also be able to share the stuff you liked with your friends / work colleagues.

Kalido Business Information Modeler - everyone should have one

I posted about Kalido Business Information Modeler back in February, but now it's gone GA and Philip Howard reviews it at IT-Director. He is pretty enthusiastic and says "everyone should have Kalido Dynamic Information Warehouse and they should certainly have Universal Information Director and Business Information Modeler too."

The only negative he comes up with is "the relatively limited number of platforms that Kalido's software runs on: one would like to see it on Netezza for example, or Teradata".

IBM FastTrack for Source To Target Mapping for DataStage

Vincent McBurney was first to report IBM FastTrack for Source To Target Mapping, and he has been followed up by Philip Howard's note "the business face of data integration" at IT-Director.

I find it interesting that releasing a simple attribute mapping tool is seen as a major breakthrough for the DataStage/Information Server family; Constellar had more or less exactly that 12 years ago (no glossary though); the UI may not have been quite so business-user friendly, but certainly supported point and click, plus simple integration with metadata repositories.

Vitria brings Web 2.0 and high transaction rates to BPM with M3O

Vitria recently announced its new M3O product, which is claims to be the convergence of BPM, Web 2.0 and Event Processing. Bloor's Simon Holloway reviews it here, where he quotes Vitria saying:

• "BPM provides standards-based executable modelling (based on BPMN) on top of business knowledge Repository.
• Web 2.0 provides the rich user experience with zero footprint to enable a collaborative design environment.
• Event processing provides the support for rule and process definition and real-time runtime performance based on event driven architecture.
• Only when you combine these together do you get a fundamentally new user experience with multilayer visualization, collaborative modelling environment, business level abstractions and event management"

Leaping shamelessly onto a passing bandwagon, Vitria explains M3O as "think iPhone meets dashboards" (quoted from ebizQ). The idea is that the "iPhone coolness" of the Web 2.0 interface will remove the gap between business and IT people. Well, as long as it doesn't (like the iPhone) lock users into an expensive long term relationship...

This looks like the first fruits from the return of JoMei Chang as CEO last July and the decision to go private, executed last March.

Cape Clear-out

I just caught up with the month-old news that Irish ESB/SOA vendor Cape Clear has been bought by WorkDay, a supplier of ERP SaaS.

Of course, SaaS needs integration, and Cape Clear CEO Annrai O'Toole promises that they will be providing the necessary Integration-on-Demand - but it seems like one of the leading independent commercial vendors has now been marginalised.

Ronan Bradley, former CEO of PolarLake (also Irish - one of our partners at SpiritSoft, and later a client of mine) also worries where the ESB market is going.

Is this a general problem in the middleware market, or is it just 'cos they is Irish? Are small vendors being caught between the rock of large vendors and the hard place of open source? Or is this (as Steve Craggs suggests in a comment on Ronan's post) simply a result of Cape Clear's own hubris?

Change of scene

My current project is coming to a sudden end, so it looks like my weekly commute from Suffolk to Lancashire will be done by Easter. I've already got two or three interesting (and very different) opportunities to consider over the weekend - and if they don't come off, there's plenty on jobserve. More news as it happens; I am looking forward to spending a little bit more time at home and a little less time on the M6.

Quantum dot memory

Next time you have trouble with i/o performance, think about this: wouldn't it be great to fit a terabyte of non-volatile RAM onto a one square inch postage stamp, with write times of 6 nanoseconds? Soon quantum-dot memory may do just that for you. That's nearly as fast as regular DRAM, and around 1000 times faster than typical flash memory. Scientists even say they could eventually get the write time down to picoseconds. Scary or what?

H-Store - a new architectural era, or just a toy?

Philip Howard's commentary Merchant relational databases: over-engineered and out-of-date? supports the idea that perhaps general purpose relational databases should now be treated as "legacy". He references a paper The End of an Architectural Era (It's time for a rewrite) by Michael Stonebraker and others from MIT.

My first thought was that RDBMS developers such as Oracle have seen off previous architectural challengers - most notably object oriented databases (OODBMS) - in the past 25-30 years. What makes Stonebraker's H-Store any different?

First, a quick summary of the paper:

• RDBMSs were designed 30 years ago - since then memory and cpu have become faster, cheaper and bigger, changing the balance against magnetic (disc) storage
• increasingly they are failing to meet today's complex challenges
• niche solutions have overtaken "general purpose" RDBMS in many areas (eg data appliances for business intelligence; specialist text search engines; etc)
• and now even OLTP, the "core competence" of the RDBMS, is no longer safe; a new approach (such as H-Store) can easily beat traditional RDBMS by cutting out non-functional architectural features (eg: redo logs stored on disc) and achieving the same goals (ACID transactions) in another way.

The paper claims that H-Store can beat a traditional RDBMS at TPC-C style benchmarks; an early version runs up to 80 times faster than "a very popular RDBMS" which itself underwent several days of tuning by a "professional DBA".

H-Store's secret sauce is that it is (in effect) single threaded. It makes the assumptions that all transactions are very fast; then it executes each transaction in turn. This gets rid of the need for complex read-consistency models. Other optimisations include keeping undo in memory (because transactions are short and sharp) and discarding it at the end of the transaction.

Well, go off and read the paper for the details, but here's what I think.

On the negative side:

• As a comparative benchmark, this fails through insufficient disclosure. For a paper that passes as academic, there is remarkably little detail on what they actually did.
• Stonebraker assumes that "most" OLTP systems can be represented by a hierarchical model - what he calls a "constrained tree application" (CTA). As a result these applications are relatively easy to partition over a shared-nothing architecture. I wonder whether this is really the case. Parts of your application may be like that, or they may be like that for some periods (during the online day, for example). But even OLTP applications need to manage longer transactions, complex reporting, and updates to the "read only" tables. In his example, he assumes (section 5.0) that the Items table is read only, so it doesn't break his tree and it can easily be replicated. But we know that new items will be added; others will be re-priced, re-categorised, phased out. Can that be handled without interrupting a 24/7 H-Store style application?
• He also seems to assume that there is only one axis of partitioning - in his case, the warehouse. But over time, the main focus of interest changes. An order is taken at a shop; it is ordered from a warehouse; it is delivered to the customer. Different "CTAs" at each stage. How does the H-Store morph its representation through the course of the information lifecycle?

On the positive side, though, this represents a call to action for the traditional vendors.

• Any performance specialist knows that the best way to tune something is to stop doing it. If we really can change the rules of the game, we can avoid all that expensive "insurance". We're used to making calculated design tradeoffs for performance; this could be just another one of those.
• I suspect that the RDBMS vendors will (more or less rapidly) steal any really good ideas. Stonebraker states that "no [RDBMS] system has had a complete redesign since its
  inception". But, like the proverbial axe, RDBMS internals have been refreshed, a piece at a time. Oracle's database kernel has had at least two major rehashes in its lifetime. It's well within Oracle's or IBM's capability to incorporate the more realistic ideas from this paper, and to find a way to blend them with current state of the art.
• They can also learn from the approach MySQL has taken of supporting multiple storage engines - horses for courses. Oracle already merges XML, relational and OLAP data stores; building in a high performance OLTP kernel to address specific classes of OLTP application is not at all inconceivable. Although it will lead to all sorts of information lifecycle difficulties, we are already used to migrating data from OLTP to OLAP; with good tool support it should be possible to work round the constraints that allow H-Store to dispense with so much that we normally take for granted.

I may revisit this paper to tease out other issues - for example Stonebraker rants against SQL (perhaps he's never got over Ingres being forced by the market to provide SQL rather than the more academically respectable Quel). H-Store uses C++, and may move to Ruby; the implication is that applications will be object-oriented, making row-by-row navigations (like so many J2EE apps, and suspiciously like COBOL/Codasyl) rather than being set-oriented.

Let's watch this space.

SYS_CONTEXT versus V$ views for getting session information

A thread on Oracle-L today sidetracked into the use of V$ views for getting hold of session information such as username, SID and module. The poster had a logon trigger that was supposed to record these items for each logon from a particular client.

I don't approve of granting access to V$ views willy nilly; best practice is always to grant the minimum privileges necessary to achieve an objective.

Another poster raised the issue of performance. In the past, SYS_CONTEXT was considered slower than direct access to the views.

So here is a test to compare the two:

---

set echo off feedback off
set timing on

set termout off

variable v_loops number;
exec :v_loops := 1000000;

set termout on

prompt Testing sys_context

declare
 l_user varchar2(30);
 l_action varchar2(32);
 l_module varchar2(48);
 l_sid number;
        l_loopcount pls_integer := :v_loops;
begin
    for i in 1..l_loopcount loop
 dbms_application_info.read_module(l_module, l_action);
 l_user := sys_context('userenv', 'session_user');
 l_sid := sys_context('userenv', 'sessionid');
    end loop;
end;
/


prompt Testing mystat

declare
 l_user varchar2(30);
 l_action varchar2(32);
 l_module varchar2(48);
 l_sid number;
        l_loopcount pls_integer := :v_loops;
begin
    -- note this only gets one of the three pieces of information
    for i in 1..l_loopcount loop
 select sid
 into   l_sid
 from   v$mystat
 where rownum = 1;
    end loop;
end;
/

---

And here are the results:

C:\sql>sqlplus testuser/testuser

SQL*Plus: Release 10.2.0.1.0 - Production on Tue Feb 26 22:23:10 2008

Copyright (c) 1982, 2005, Oracle.  All rights reserved.


Connected to:
Oracle Database 10g Express Edition Release 10.2.0.1.0 - Production

SQL> @sys_context_test
Testing sys_context
Elapsed: 00:00:07.31
Testing mystat
Elapsed: 00:00:38.57
SQL>

I suspect that in the past SYS_CONTEXT issued recursive SQL under the covers (just as the SYSDATE pl/sql functions used to, and the USER function and the 11g assignment from a sequence still do).

Now I assume SYS_CONTEXT gets its information directly.