Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

Denis Gobo — Mon, 30 Jul 2007 14:23:58 GMT

well you could say the boat is a slowly changing dimesnsion and is indeed the same boat. ;-)

In the future we will run into this as humans. If you replace a heart, a leg and and a knee with artificial ones are you still human? What if you replace the brain? Does it depend on what you have replaced which will qualify you as a human or not?

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

Adam Machanic — Mon, 30 Jul 2007 14:33:50 GMT

We already run into this as humans--our bodies are always shedding cells and creating new ones. Also, think about cutting yourself and having the skin grow back, or getting a haircut... Change is a constant. Luckily, we don't generally need to track things at such a level of detail in database systems :)

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

ML — Mon, 30 Jul 2007 15:09:52 GMT

We need to distinguish between the ubiquitous logical concept of a boat and its transient physical implementation.

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

Adam Machanic — Mon, 30 Jul 2007 15:20:01 GMT

ML: That sounds like Plato's "forms" in "The Republic"... But I don't think that applies to to this discussion as I'm referring to handling of actual instances rather than types. So the question is not, "is the QE2 still a boat after she gets a new paint job," but rather, "is the QE2 still the same QE2 after she gets a new paint job?"

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

Denis Gobo — Mon, 30 Jul 2007 15:30:12 GMT

Well to answer that we just have to answer this

Is Pamela Anderson still the same Pamela Anderson after <list all jobs here> ;-)

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

Adam Machanic — Mon, 30 Jul 2007 15:43:46 GMT

First we need to figure out if you're still human with all of that plastic in you... <VBG>

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

ML — Mon, 30 Jul 2007 15:44:08 GMT

QE2 is QE2 regardless of any of its attributes. If we attach wheels to it will it cease to be the entity that it used to be?

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

Adam Machanic — Mon, 30 Jul 2007 15:48:40 GMT

This is why we need to differentiate between identity and being. To name something is not to define it or describe its current state.

re: Programmatic Concurrency Control: Do Simultaneous Updates to Different Columns Constitute a Collision?

ML — Mon, 30 Jul 2007 15:53:24 GMT

We name things to help us distinguish between different instances. Then we rename them to confuse innocent by-standers. ;)