For anyone who has ever watched the classic British mini-series “The Prisoner” this is a very recognizable line. But it applies to many parts of our lives.
This is a tale of hiking, a non-cave rescue, and yes, eventually Extended Events.
“I went to the woods…”
This past weekend I spent some time in the woods hiking and getting away from it all. This is the first time in literally decades I had done an overnight hike on the Appalachian Trail. My goal was to get in an overnight and work on closing a gap of it that I had not yet hiked.
The last time I hiked the trail, cell phones were a very rare item, carried by business people only and often weighing several pounds, they certainly weren’t something the average hiker could afford, and even if they could, they would be too heavy to carry.
I mention this because I had fully intended to carry mine with me, so that I could take pictures, and perhaps even, I’ll admit it, if I had connectivity when I camped that night, catch up on some Wikipedia reading, or send a picture or two to friends and family. But alas, about 2 miles into the hike, at a gorgeous viewpoint (see older photo above), I stopped, tried to pull out my phone and realized that unsettled feeling I had at my car before locking it wasn’t “Am I sure I have my keys” but really should have been “am I sure I have my phone!”
It turns out, other than my inability to document my trip with some photos, and not being able to call my wife to let her know I’d be at the pick-up point much earlier than we had planned, not having access to information of the outside world was a refreshing change of pace. I’m almost glad I didn’t have my phone.
A Missed Call
As some of my readers know, besides being a DBA, I also teach and at times perform cave rescues. As I tell folks once they get past the “That’s so cool” phase, it’s not really all that glamorous. If I get called out to one actual rescue a year here in the Northeast, it’s a busy year. But, on warm weekends in the summer, the odds are higher than say the middle of the week in the winter (though that has happened too).
So a concern I had in regards to not having my phone was that I would miss a call for a potential rescue.
It turns out I was partially correct in my concern. On the way home, I saw my phone buzz. I didn’t answer it, but a few minutes later did glance down to see “Missed Call”. It was from my team co-captain. (To be transparent here, the terms team and co-captain are used loosely, it’s not a very formal setup). She rarely calls, especially if it’s a weekend, except in an emergency. I waited until I got home to call her back. And it wasn’t an actual call-out, yet. It was at this point a “potential missing caver.” What this meant in this case was a vehicle had been spotted outside a popular cave, and it had been there for at least 18 hours. That is unusual for this cave, most trips are 2-3 hours in length. So, this was concerning. But, we didn’t have enough information. Was someone in the cave? If so, where? Were they in need of assistance? We needed information, and by hook or by crook we were going to get it. Or at least some of it.
In general, one of the biggest issues we have when starting a cave rescue is the lack of information. In this case case it was even, “are they in the cave?” Had we determined they most likely were, the next question would have been, “where?”. That shapes our search. “How long?” That might shape what equipment we bring on our initial search. “What injuries?” That would also shape our response. In any cave rescue we eventually get the information, but it can be frustrating to have to wait. Caves don’t have cell service inside. (We often do literally put our own phone system into caves during a rescue however!) When we train folks, they often find it hard to believe at first that a patient could be 300 feet into a cave, and it would take a skilled, fresh caver 45 minutes to simply get to them, and another 45 minutes to get back. So as simple a request as “can you get me information about the patient” could easily take 90 minutes or more. And yes, that’s a real life incident.
In this case, eventually the authorities ran the plates and it appears the plates had expired before 1990, the VIN that could be found on the insurance card sitting on the dashboard was made up (or belonged to a vehicle decades older) and the address on the card was fake. We stood down. There wasn’t going to be a search that day. It was entirely a police matter.
#TeamExEvents
I said I’d get to Extended Events and here we are. I’ve written about them before and I’m a huge fan of them. Simply put, if you’re not using them, you’re probably missing information that you can very useful. I started in the days of SQL Server 4.21a, but really started to cut my teeth on SQL Server with 6.5 came out. Back then our problem sets were probably easier and smaller, but we still dealt with similar issues, the biggest has often been performance related. In the early days there were some decent tricks and ways of diagnosing where your performance bottlenecks were, but to be honest, sometimes it was hit or mess. Over the years, Microsoft has added a lot of functionality to SQL Server including DMVs and Extended Events. I now routinely use Extended Events to track down performance issues or other problems. Last night at our local User Group Meeting, Grant Fritchey did a lightning round where he highlighted one of the features of Extended Events that honestly, I know about, but don’t use enough: Causality Tracking

Causality Tracking extends the power of Extended Events to a new Level!
Let’s just say this is a feature that makes picking out the specific events you want to follow much easier. The example Grant gave showed a ton of detail, more than you’d normally need, but extremely useful if you did in fact need it. In other words a simple checkbox can now give us a great deal of useful information.
With the right information, you can often identify bottlenecks and make huge performance gains.
At times I feel like I’m Number Six, trying to get information about a database problem or a potential cave rescue…
Number Six: Where am I?
Number Two: In the village.
Six: What do you want?
Two: Information.
Six: Whose side are you on?
Two: That would be telling. We want information…information… information!!!
Six: You won’t get it!
Two: By hook or by crook, we will.
In conclusion, there are times when disconnecting from the information around us can make a weekend in the woods more enjoyable, but a dearth of it is standard at the start of a cave rescue, while having ready access to it can make solving a problem far easier.
Where do you stand on the information spectrum today? Do you have a lack of it, the right amount, or too much?