onsdag den 25. august 2010

SQL SAN and the beauty of databases

Now its SQLserver 2008 R2 - Ive just tried it. But how did I get there ?

The engineers who know me like Tam, Rasmus and Lars will know I have a long standing love affair with databases, going back to the linked list RTE-A database of FLS Automation lore.

At AN I worked on many factory database projects with Novo in Hillerød and FLS order handling system
There I invented having state action tables and procedures stored in an Oracle tablespace. I also learned the importance of precompiling and database tuning, because before that was done by FLS expert, the bright system worked in syrup...
One lovely thing in debugging was that the Pro*C data events cold be rolled back before commit enabling a datainput scenario to be replayed as many times as needed.

Later at AN I ws quite fascinated by Arnes DB2 developer interface tables with not just ER descriptions but functional sequence descriptions enabling each developer to understand the dynamic context of each attribute, e.g. reading a barcode from a ingredients bag, triggering a lookup for next serial number to be printed.

Simple, well, Yes but if You compared to the usual terse attribute names You realise that Arnes notation with a functional comment enables one to supplement e.g. 'Serial/Lot Number' with information describing the data update direction.

That is : Is the serial number to be read from the bag or is it to be printed to the bag.
So in this way we could individually adapt SW to the interface tables, and join together ourselves and our code on site. Beautiful engineering.

At Bombardier /Adtranz we worked with off-line databas schemas paralleling the SW structure insofar as the adaptation to the rail autority standard pictures, symbols, user commands and the particular line infrastrure objects, as well the current status for Hot standby operation, enabling seamless failover.
Also this enabled updates from the online 'kangaroo' databases to the Oracle schemas, allowing for precise backup and restore following Oracles standard tools.

Later at H:S working with the Lotus Learing database on Websphere I used a Oracle 9 system. purchasing licenses. definning tablespaces, users and storing the base on SAN for efficiency and safety.
Contrary to the H:S guys way of using KVM switches I decided to use my Bombardier. experience witt X-Windows servers for PCs, finding LabF from Tampere to maintain the DBA job.
When starting trial run with hospitals we had quite some mysterious breakdowns of the DB, which nobody could figure out, until I realised the breakdowns coincided with stand-by events on my PC thus closing the X-session on the AIX machine. Well, In my defense, even if I created the problem by using X on PC, I also was the only one to realise the source of errror.

The SAN proved to be a mixed blessing though, as some will know a IBM SAN provides storage through dedicated interface cards acting as AIX/ volumes. Budgetary reasons prevented me from attending the IBM courses on the connected issues, and when the SAN connection broke down at one time I was unable to reach Hvidovre in person, and could just point out that a 'hard' reset would prevent either accessing either the still online backup files not yet spooled out to tape, as well as the online database setting back learning system configuration one week.

While I was been killed remote over the mobile and probably from the sound of him, in effigium by the manager, I did point out that we should call IBM before deciding.

Could IBM solve the issue ? Of course they had a proper way of reeastablishing the connection, and just as sure good old big blue had made certain You either needed to have taken the SAN courses OR had to call for technical service.
Moral: Even if a SAN is supposed to be better than RAID anything make sure You dont put all You eggs in there...

Lastly I've worked with SQLserver at ITS holding schemas for the EDIFACT systems orders and recognition fields, and while its different to Oracle, Microsoft seems to be building the Technet to a comparable level.

You know what ? Back when I first started to juggle SQLnet connections and using SQL professionally, the logic and mental challenge of designing queries I've found it just as if not more exciting than coding because the dataset could be anything in the world.

That leaves me with associations (smiling) to Mickey Mouse in the Vizards Apprentice.

IHC Work ongoing







You recall the IHC I have been cabling, terminating and working on since we moved in our new House ?
Yippeee !!
Amazingly but not surprising my sense of engineering has enabled me to work on/off with sometimes pauses of three months between work packages, e.g. cabling the alarm/shell integrity circuits last summer with a bit of faultfinding on cut cables where the insulation guy seems to have cut the cable installed by the electrician.

Last fall before beginning the hopefully temp job as a busdriver, I cabled all cores for the downstairs controller, fitting the battery backup and most importantly the smoke/fire indicators, so finally we are legal.

Now after the summers vacation I have the odd mid week day off from driving and I has now tested, verified and put the house alarm on-line.

Remaining work will consist of cabling the upstairs controller, connecting all remaing switches and also connecting all the occasionally used power outlets to a timed switch to save at power expenses for the relay outputs.
We have come a very long way from when we moved into the house in january 2007, where I was to be off for SriLanka with Brodersen, where I had to set up the table PC with the propietary software to enable Annette and Maria to turn on the lights as at that time no inputs had been connected- only the 230V outputs mounted by the licensed electrician. And it was dark scandinavian winter....

Last news and 2010 summers vacation

Pia: Is now in Bolivia again working for UNIFEM Andina, this time ...
De Accuerdo ese no se puede ser in Ingles, Entonces por Espanol.
Pia esta una vez mas in Latino America, hoy in Boivia, trabachando por UNIFEM in Cochabamba, para obtener su dissertaction de estudios Sociales in Lund Suecia.
Buena suerte, cara :-)





Nosotros, Oh heck, Us others just had a nice vacation in Marielyst on Falkevej just next door to the house we rented up til 10 years ago, and as usual we also managed to fit in preparations for a birthday again.
Tricking myself a bit I managed to insist to myself that I had a deadline on the IHC house controller alarm and also the BMW passenger front seat (which to be frank had awaited finishing since march 2006) reclothing, though the drivers seat was finished at that time.


This time Marias 11 years birthday in three installments, the classmates, Then Anettes sisters, Then my cousin Susanne with lovely Marianne and Niels and Charlotte and Lars. Maria thus managed to get three for one :-)








The school classmates party was a huge success, even if the weather, which as You may know has been fickle with monsoonlike rains, made us move from the terrace and inside. The Beolab 6000 speakers also had premiere being moved downstairs to Marias room using the PowerLink connection via IHC from the B&O Ouverture we bought last Year, playing streamed TDC music from WMP on our Media Center via the Sony flatscreen TV.
Technical note: We had problems with power hum noise on the TV - Ouverture connection but replacing the video card in the Media Centre with a full HDMI/HD ATI Radeon card allowing the sound to be sent digitally to the Sony TV , this noise has disappeared.
The boys loved the speakers, the girls danced :-)
And us parents? We are happy when Maria is happy. Our little kids are now pushing just a bit at being teenagers. Time flies, and did I hear that from my own parents not believing it of course, well now I know better:-)