Steve Thompson-454462 (1/17/2013)
In discussing Isolation, I thought the analogy of the pizza box was clever and appropriate. However then you go on to say:if I'm updating customer information in my database, it should not prevent another process from reading customer information
That sounds like you could be promoting the idea of allowing dirty reads, which I never thought of as being a requirement of supporting the Isolation tenet (though I'm far from an expert); in fact, couldn't that be considered a violation of consistency?
Actually, I'm not promoting dirty reads. What I'm promoting is the idea of access to previously committed data. Just because Mary Sue's last name is being updated to her new last name does not mean another process shouldn't be able to read the previous last name at the same time.
Now I grant there are all sorts of other concerns that go along with that, but for the purposes of the 50k foot view, that's basically what I meant.
Oh and before I forget, for your next article can you work in a reference to Disco Stu (maybe something like, "Disco Stu likes disc defragmentation")?
Heh. I'll see what I can do.