This week I’ve been up in Manchester, the city of my birth, to run the latest in our PDMv2 training courses.

We’ve always done a bit of training on request, but, in response to popular demand, we are now offering more public courses. We’ll be popping up a list of dates on the website shortly but if you want to know more about training in the only openly published Data Migration methodology, drop me an email at the address below.

I also apologise for the irregularity of these blogs. This week’s excuse is, of course, that I was out of the office and couldn’t therefore type one. A totally pathetic excuse I know. Once again I vow to try harder and make time available. I did, of course, have my laptop with me, but after a day on my feet in pedagogy I was too tired to do much in the way of thinking let alone writing. The feed back from the course was good, which is reassuring. Biggest criticism being that it was a bit too much chalk and talk and not enough interaction. We will have rectified this by the time our April course comes around.

One of the many subject matters that resonated with the attendees was the Reality Check. Now the reality check, for those of you who are newcomers to PDM or to this blog, is the data gap that occurs between the world as it really exists outside of the computer system and the world as seen from the computer system. I have seen whole floors of hotel rooms missing from the data we had to load.

Reality Gaps are sometimes the hardest to spot because the data as it exists matches all the validation criteria, it looks perfectly all right. It just doesn’t match reality. On returning home I’m confronted by just such an issue.

Our local newspaper report the case to Gordon Buchanan and his battle over bills raised by British Gas - the utility that supplies gas, mostly via underground pipes to a substantial part of the population of Britain for heating and cooking. These bills have been hitting his door mat for the last 5 plus years. He feels that he is within his rights to challenge them because not only is he an upstanding member of the community who pays his bills, but he doesn’t have a gas supply to his house. He is confident of this because British Gas does not even have a supply to the village where he lives a fact confirmed by BG themselves.

The error has been blamed on a new billing system (well not so new now I guess if this has been going on since 2005) loading bill delivery addresses in place of service delivery addresses. But it all points to the potential problems of reality errors and their consequences. One person harassed for five years and one company publicly humbled. And now I’ve added my bit of humiliation as well.

What is always surprising with these stories, of course, is the length of time it takes to correct errors. Once the data is in the system it takes on a reality of its own. There are not always any correction mechanisms built into the new application. All of which gives us more reasons for getting it right in the first place.

So just a short blast from me this week - next week I think I’ll be talking about beer and data migration, two of my favourite topics.

About the author

John Morris has over 20 years experience in IT as a programmer, business analyst, project manager and data architect. He has spent the last 10 years working exclusively on data migration and system integration projects. John is the author of Practical Data Migration.