For this month's T-SQL Tuesday, Kerry Tyler asks us to talk about something that went wrong. Since I already gave a pretty self-deprecating account of a recent mistake I made last month, let's dig into a short lesson from ancient history for this one.

Back in the early 2000s, I did a lot of side work. Young, single, early in my career, and living a party life in Newport, the extra income I could derive from spare-time database-slinging came in very handy. Some of the projects I worked on in this period also became blog posts later (like Readable Secondaries on a Budget, an idea I implemented before AGs were a thing), but some projects I'd like to forget.

One such project was with a company managing a well-known college financial aid database. My work (almost all remote) was limited to about 5-10 hours per week; mostly schema development and performance tuning. We had a weekly conference call which sometimes involved me, but usually didn't. I always attended, but I would multi-task — stay current on e-mail, review alerts from my real job, answer softball questions on the newsgroups, that kind of thing.

Inevitably, there was an occasion where I was doing some of this multi-tasking, while I was ducked into a meeting room at my job, attending this conference call. I was working away on something, registering only that someone on the call was talking. Then suddenly:

Aaron, what do you think?

I panicked. What did they ask? Surely they were just asking me to confirm that something sounded right to me? So I replied:

Yeah, I think that idea is sound.

I got a call 10 minutes later that my consulting agreement had been terminated, effective immediately, because I had been asked an "A or B" question, clearly hadn't been paying attention, and then tried to bluff my way out of it.

Some lessons from this that I have struggled with my entire career:

• don't double-dip
• don't multi-task
• if you're going to do either, don't do both simultaneously
• if you miss a question, don't bullshit

This is not rocket science by any means, but hopefully it helps someone.