meshbrains

Unix tools amaze me on a daily basis. Maybe I’m easy to amaze… Today I was doing a pretty good size data migration. I had to pull some 30,000 products based on two differing criteria: items selling at once in the last two years, plus any products added in the last 60 days or so, regardless of sales. Two pretty wicked SQL queries later and I had the data I was looking for dumped out to CSV. One last step was to merge the two csv files, filtering out the uniques between the two and sorting.

I could have gone back and done this by creating temp tables, some more joins, pinch of black magic, but it turns out it was much faster to pump them through:

cat file1.csv file2.csv | sort | uniq > file3.csv

This little one liner takes the contents of both file1 and file2, sorts them, removes duplicates, and pumps the resulting uniques out to file3. On files containing some 30k lines, this finishes in seconds. Seconds.

I read a lot, and re-read a lot. It drives my wife nuts. I was re-reading a classic, The Design of Everyday Things by Donald Norman. I came across a part of Chapter 4, Knowing What to Do entitled ‘Making the Visible Invisible.’ This tied in with an incident recently that is probably causing a vacuum manufacturer unnecessary grief and customers unneeded confusion.

Picked up a vacuum cleaner a few weeks ago. The old one was a Riccar and lasted 14 years. We should have replaced it with another Riccar. I digress. The interesting point of this story is that I purchased the same new vacuum twice.

Cub Scout den meeting was at our house and somehow glitter was involved. It was everywhere. My neanderthal perception is that a Cub Scout den meeting should involve pointy dangerous objects and fire. I digress. When all the carnage was complete and everyone went home, I dutifully pulled out the vacuum cleaner. Turned it on and the brush roller wouldn’t turn.

There are only two switches, Power and Brush. I know the brush roller has worked, I’ve seen it. The vacuum motor worked fine and the front lamp came on. However, switching the Brush switch on and off had no effect. Odd. I checked the electrical contacts, removed and reseated all the filters. I flipped it upside and removed the roller and drive belt to clear any hair. Still nothing. Must be a blown fuse in the roller assembly.

Took it back to Costco who cheerfully refunded my purchase and I bought another one. When I got it home and assembled it, I went through the instructions to see if I missed anything. There it was… the brush only turns if the Brush switch is on AND the vacuum is reclined.

Why is it like that? In all my years on this earth, I know that if the vacuum is upright when I turn it on and the brush is turning, I should turn the brush off or I may burn out the motor. Some clever engineer decided to make that fail-safe by not allowing the brush to turn, despite the presence of a clearly labelled Brush switch. Thus the reference to the DoET book and ‘Making the visible invisible.’

I’m not sure if the flaw is due to the ‘hidden’ recline switch that works serially with the visible Brush switch, or if the flaw is that there is no feedback mechanism to tell me what’s wrong. The design forces me to learn something unnecessary to accommodate the vacuum cleaner.

The impact of this design is that I probably returned a perfectly good vacuum cleaner. How much does that cost the manufacturer? I can tell you how much aggravation it caused at least one consumer.

Came across Balsamiq Mockups the other day. What a great tool! In an day of agile development and Photoshop wizardry, clients have a tendency to walk away from a mockup reveal to believe that a feature complete design is ready for release. Usually, that’s very far from the truth. The problem is compounded because they’ve seen ‘what it can be’ and transferred that perception to ‘what is.’

 Balsamic provides a way to create the UI in an iterative fashion with the client while making perfectly clear the scaffolded nature of the design. Clever!