I think I speak for many DBAs when they say they’ve all had a programmer tell them, “The database is too slow, we need faster hardware.” Then as a DBA, you go in, look at their query and realize they’re running a table scan across a huge 100GB plus table without any indices. You analyze the data and overall usage further and decide to put in an index and suddenly their query is running in sub-second times instead of minutes.
Or, in a case I was working with with a client years ago, they had a stored procedure that sometimes would suddenly get slow. Their solution was to occasionally issue a WITH RECOMPILE command when calling it and things would get better. It worked, but was hardly ideal. After analyzing the stored procedure and usage I realized that it was suffering from a form of parameter sniffing and with a bit of work I was able to recommend a rewrite that solved their problem in a better way.
What is critical here is understanding HOW exactly data is stored and how the query engine works and how we can take advantage of how the database engine works to improve things.
And honestly, for me, I’ve always loved understanding “how things work.” I’ve marveled at seeing Bob Ward open up the debugger, live on stage, and show how a particular piece of code in the SQL engine works.
And now, I’m starting to undergo the same journey in the human body.
Let me caveat things by saying I am only half-way through my Anatomy & Physiology I class (and same with my Bio I class) and I greatly recognize how much more I have yet to learn (and that’s only out of what we know. We’re still learning more!)
However, I continue to be blown away with “how things work.” Mother Nature has had millions and millions of years to make things work. What strikes me as interesting at times is how both conservative and ingenious things can be. We all start from a single cell that divides and forms a sphere of cells. This soon forms a neural tube and then starts to specialize further. Somehow from that single cell we end up with our feet at one end and our skull at the other, completely different, but from the same source.
But, even then when you dig deeper you realize that at some level hands are really feet, but with an opposable joint and far more flexibility and dexterity. The internal structures are very similar. Then you move up to the arms and legs and realize even the limbs start out fairly similar: the upper limb has a single main bone and the lower limb has two bones. Of course the joints start to differ, a knee joint is VERY different from an elbow joint. Nature is conservative.
This week we started to study skeletal muscles and how they work. This builds on earlier lessons in both the parts of a cell and histology. A generic animal cell has sort of a skeleton made up of fibers the cell produces. These fibers can come in one of several forms. In most cases they’re simply there to give a certain structure to the cell, or perhaps via the use of other proteins, connect to other cells. They often may look haphazard in design and function, but they get the job done.
Until you look at skeletal muscle. Then you see two of the fibers are laid out a bit differently. One, the thin “actin” fibers are laid out radially around larger fibers, the myosin. You may see these fibers in other cells, but in muscle cells their layout is different. And this makes all the difference. The myosin fibers have “heads” on them that can, in the right circumstances both attach to the actin fiber, but also essentially pull on it by flipping its head from a “forward” to a “backwards” position. The head can then release, flop back to its original position, grab the actin again, and again flip back to the tail facing position. I’ve left out a lot of details, but if you think of yourself using both hands to pull upon a rope, you get the same basic idea. Or, for the caving readers among me, it’s a pair of handled ascenders and it’s basically using a Texas system!
To me, this is really an ingenious re-use of existing structures inside the cell. The more I learn about the human body (or biology in general) the more I’m amazed.
I’m loving “seeing under the covers” and this is part of it!