I still remember the day. I was working for a large systems integrator on a very major account, and had responsibility for some DB2 databases, but also had the unfortunate duty of also taking care of some legacy IMS databases (hierarchical IBM databases used quite a lot ‘back in the day’), which I knew next to nothing about. One morning I was asked to make a small change to a very large and prominent IMS database – just remove one record – what could go wrong? The guy who knew IMS real well was gone so I put together a program to do the job (yes, you actually had to write a program to do it), and ran it after hours. I came in the next day and tried to access some records in the database. Nothing. All gone, except for – ta-da – the one record I wanted to remove! At the instant I realized my mistake, I was acutely aware of two things: (1) I was in serious trouble if I didn’t have a backup, and (2) I was in desperate need of a complete change in underwear.

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