Common prefix skipping, adaptive sort | Hacker News Reader

Common prefix skipping, adaptive sort

smalldatum.blogspot.com

Oracle's claims about speed-ups of their database are just that, claims. Their licenses explicitly disallow benchmarking, so basically we are legally bound to rely on their word.

TFA is a post by the author of the algorithm, talking about the performance they originally predicted and later observed after implementing it while they were working at oracle, now that the patent has expired and anyone can implement the algorithm.

So:

- you are calling them a liar

- and are asserting you can not evaluate the claim even though you can implement and benchmark the algorithm in whatever DBMS you favour

I can evaluate the claim now, but I would not have been able to evaluate the speed gain of an Oracle database using whatever proprietary implementation they are using. Claiming I've called author anything is putting words in my mouth.

> I can evaluate the claim now

And the article is now. What luck!

> I would not have been able to evaluate the speed gain of an Oracle database using whatever proprietary implementation they are using.

Which has nothing to do with the article. In fact it has less than nothing to do with anything, as even the original whitepaper goes through great lengths to specify that it's lab observations and only compares versions of oracle, none of which would have been relevant to you if you'd refused to use oracle in the first place.

And Oracle never forbid running benchmarks (maybe they could now, they wouldn't have had the tracking and C3 to do so back in the 80s), DeWitt Clauses forbid publishing benchmarks without prior approval.

> Claiming I've called author anything is putting words in my mouth.

You're asserting that you can not trust oracle's numbers, in response to an article by a (former) oracle employee talking about "their" sort algorithm and the numbers it got.

There are only two possibilities here:

1. you got hopelessly lost in both space and time as you were looking for a 20 years ago thread on the linked oracle whitepaper, and your comments have nothing to do with TFA

2. you're calling the TFAA a liar who can not be trusted, given they're the author of the algorithm, givesthe same number, and in fact originally derived the rough gain when implementing and benchmarking the algorithm:

> once I had this implemented within the Oracle DBMS I was able to compare it with the old sort. The new sort was often about 5 times faster than the old sort.

So which is it?

Can you extrapolate a bit more from my post? It's clear that I've put massive amounts of research into it.

Claims do not support themselves. The claim is unsupported by evidence and thus the burden of proof is on them or you to produce that evidence.

As the author and implementer of the algorithm allegedly prepared, ran, and analyzed benchmarks they obviously, by far, have the easiest time producing the evidence for their claim. Your argument that the poster needs to go read, implement, integrate, and benchmark the algorithm to to generate evidence to counter the absence of evidence for the claim is ridiculous. It would be as easy as 1-2-3 for the author to present their evidence to meet their burden of proof, yet you are demanding a extraordinary level of effort by the poster to present evidence against when they do not even have the burden of proof.

This is further ridiculous because the author or you would merely need to support the positive claim, where as you are demanding the poster demonstrate the negative, and all this before there is any evidence.

You should really stop with the unnecessarily combative tone when your entire model of argumentation is completely backwards in every respect.

> Claims do not support themselves. The claim is unsupported by evidence and thus the burden of proof is on them or you to produce that evidence.

OK?

> Your argument that the poster needs to go read, implement, integrate, and benchmark the algorithm to to generate evidence to counter the absence of evidence for the claim is ridiculous.

The poster didn't complain that evaluating the claim was work they couldn't be arsed to do, they complained that they could not evaluate the claim because they were legally bound to accept it. Both parts of that declaration were and are factually wrong.

> It would be as easy as 1-2-3 for the author to present their evidence

The author implemented this algorithm as an employee 20 years ago, they do not own and can not provide the original code, they would have to reimplement it from scratch (possibly from the patent if they didn't otherwise publish it, which I assume they did not since they link to the white paper but not an actual paper and apparently had to make up a name for it just now). They might have an edge from being more familiar with the domain, but given the poster's dismissal I'm sure they're deeply familiar with the subject.

And given the tone, the author is (well was, the post is 6 months old) just showing this cool thing they made back then, which they can now usefully talk about (since previously it was patent-encumbered), and give some history for.

> you are demanding the poster demonstrate the negative

I am doing no such thing.

Their license only disallows publishing the result of a benchmark

But you were always allowed to run your own benchmarks internally.

Back then, you could have installed 10gR1 and 10gR2 and compare the sort performance on identical data sets and queries.

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