Math and Computing
Paul Graham, writing about Lisp:
“So the short explanation of why this 1950s language (Lisp) is not obsolete is that it was not technology but math, and math doesn't get stale.”
I'll make the same claim about the relational model, which is just an application of set theory and first-order predicate logic. Fabian Pascal puts it this way:
· a database is a set of axioms;
· the response to a query is a theorem;
· the process of deriving the theorem from the axioms is a proof;
· a proof is made by manipulating symbols according to agreed mathematical rules;
The proof, of course, can only be as sound and consistent as the rules are. That makes the DBMS a deductive logic system: it derives new facts (query results) from a set of user asserted facts (the database). The derived facts are true (query results are correct) if and only if:
· The initial assertions are true
· The derivation rules are logically sound
The sad fact is that none of the above is true of commercial SQL DBMS's. They're just stale technology - because they ignored the math.
Saturday, August 09, 2003
Dolphins
We saw a group (school?) of dolphins this morning at the beach. I saw 4 together, but S. says she counted 8 total while I was trying to get a picture (I didn't; need a better camera and a better photographer). They tend to swim parallel to the beach just past the surf line, their fins bobbing up and down. I usually see them from October to April, but I've never seen them before in August. From the descriptions I read, I'd guess that they were bottlenose dolphins but they could also have been Pacific White-Sided Dolphins. Doesn't matter; either way, it's a striking reminder that we live right next to one of the greatest concentrations of marine life in the world.
We saw a group (school?) of dolphins this morning at the beach. I saw 4 together, but S. says she counted 8 total while I was trying to get a picture (I didn't; need a better camera and a better photographer). They tend to swim parallel to the beach just past the surf line, their fins bobbing up and down. I usually see them from October to April, but I've never seen them before in August. From the descriptions I read, I'd guess that they were bottlenose dolphins but they could also have been Pacific White-Sided Dolphins. Doesn't matter; either way, it's a striking reminder that we live right next to one of the greatest concentrations of marine life in the world.
Thursday, August 07, 2003
Follow ups
IBM countersues SCO, following Red Hat and SUSE. Apparently triggered by SCO's attempt to sell SCO Unixware licenses to Linux users, which, BTW, is a violation of the GPL. Bruce Perens points this out, and also points out the danger of patents to Open Source, which is worrisome given that part of IBM's countersuit alleges patent infringement.
So this is more of a mess than ever. I still don't believe there's any real merit to SCO's claims. But the FUD spewed by all this is a terrific smokescreen for more serious attacks on Open Source - namely, patents and other manipulations of IP protections.
What's the situation in Iraq? Depends on who want to believe. All I know is that two more U.S. soldiers are dead in an attack and more than 10 Iraqis died in a car-bombing of the Jordanian embassy in Baghdad. Read Salam Pax for an insider's view.
Winning? Losing? The peace, that is.
IBM countersues SCO, following Red Hat and SUSE. Apparently triggered by SCO's attempt to sell SCO Unixware licenses to Linux users, which, BTW, is a violation of the GPL. Bruce Perens points this out, and also points out the danger of patents to Open Source, which is worrisome given that part of IBM's countersuit alleges patent infringement.
So this is more of a mess than ever. I still don't believe there's any real merit to SCO's claims. But the FUD spewed by all this is a terrific smokescreen for more serious attacks on Open Source - namely, patents and other manipulations of IP protections.
What's the situation in Iraq? Depends on who want to believe. All I know is that two more U.S. soldiers are dead in an attack and more than 10 Iraqis died in a car-bombing of the Jordanian embassy in Baghdad. Read Salam Pax for an insider's view.
Winning? Losing? The peace, that is.
Monday, August 04, 2003
Life
This is the time of year when the Amaryllis blooms. The local variety are a startling pink, gay and profuse. They seem to bloom overnight; you look up one day at the beginning of August and notice them everywhere. It's interesting that they choose to bloom at the least likely time - when the morning fog no longer rolls in and the sun beats down all day and it's bone dry. And they seem to grow best in empty lots, quiet corners, and other forgotten or ignored places. They only last for a few weeks and then they're gone. That, combined with the time of year, when summer peaks and then declines into the autumn, makes them very poignant to me; I feel summer's glory and passing all at once.
I also notice that the leaves on the Japanese Maples in front of Gault Elementary school are starting to turn red, getting ready to blaze with color and fall at the feet of the children when they return to school in just a few weeks.
I know neither the Amaryllis nor the Japanese Maple are native varieties, but I can't help but love them anyway.
This is the time of year when the Amaryllis blooms. The local variety are a startling pink, gay and profuse. They seem to bloom overnight; you look up one day at the beginning of August and notice them everywhere. It's interesting that they choose to bloom at the least likely time - when the morning fog no longer rolls in and the sun beats down all day and it's bone dry. And they seem to grow best in empty lots, quiet corners, and other forgotten or ignored places. They only last for a few weeks and then they're gone. That, combined with the time of year, when summer peaks and then declines into the autumn, makes them very poignant to me; I feel summer's glory and passing all at once.
I also notice that the leaves on the Japanese Maples in front of Gault Elementary school are starting to turn red, getting ready to blaze with color and fall at the feet of the children when they return to school in just a few weeks.
I know neither the Amaryllis nor the Japanese Maple are native varieties, but I can't help but love them anyway.
An Abrupt Hiatus
I can't believe that I haven't blogged for a week. There's a lot of things I want to write about, but just haven't had the time; I've had to work on some critical customer issues at my new job and was also working on a little programming contest we had staged. Alas, I came in third. The winner was our intern, who used a friggin' Mergesort as the basis of his solution. Oh, the ignominy! At least I beat my boss and a couple of the other senior programmers.
I can't believe that I haven't blogged for a week. There's a lot of things I want to write about, but just haven't had the time; I've had to work on some critical customer issues at my new job and was also working on a little programming contest we had staged. Alas, I came in third. The winner was our intern, who used a friggin' Mergesort as the basis of his solution. Oh, the ignominy! At least I beat my boss and a couple of the other senior programmers.
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