
A New Frontier in Databases with AllegroCache - mqt
http://www.defmacro.org/ramblings/relational.html
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dabeeeenster
"The main contender, ReiserFS, dropped out of the race because its creator
decided to pursue other interests, but other than that everything is the
same."

Nice...

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signa11
my favorite is "...mathematics has no expiration date". it echoes quite well
with pg's assertion (on why lisp is not obsolete, in revenge of nerds) "...it
was not technology but math, and math doesn't get stale"

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henning
The rub in this case is that Franz's licensing terms (involving royalties on
the products you create using their product) are even more heinous than
typical proprietary software.

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cridal
If that's true, it's really nice! Just like voluntarily implanting a blood
sucking parasite into your neck.

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jm4
This is totally off topic... Is it really necessary to mod someone down to -8?
Sure, the comment deserved to be modded down, but isn't -1 or -2 enough? At
that point the font changes to light gray and you can barely see it anyway. It
seems like modding it down after that is just beating a dead horse. I could
understand if it was offensive, but this is a typical stupid comment that
doesn't contribute to the discussion.

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osi
their software is ridiculously fast. one problem (in the 2.x series), is that
there were NO CONCURRENT READS from the database. all access was serialized.

it looks like they may have addressed that in 3.x by allowing read-only
copies, but still, c'mon!

if your workload is one that can deal with those limitations, its an awesome
product. but it definitely restricts the areas-of-use.

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davidmathers
"In the example above (likes julie ?x), x refers to everyone in the database
defined in the second place of the binary relation likes. Note that the
variable x must mean the same person in (likes julie ?x) and (likes ?x ?y).
Similarly, the variable y must mean the same thing in (likes ?x ?y) and (girl
?y). Intuitively, the clause above says that Julie likes some person x if
there is some person y that x likes who is a girl. Or, as we said originally,
Julie likes anyone who likes girls. Can you represent this information in a
traditional database?"

Yes/no depending on your perspective. "anyone who likes girls" is a variable
so you have to convert it to a domain: "everyone who likes girls."

Is there a difference? Using a domain seems more useful to me, but maybe my
brain has been corrupted by too much database work.

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coffeemug
You can convert this to a domain, but I'm still not sure how to say Julie
likes everyone who likes girls. Using dependent data definitions in SQL gets
very tricky very quickly. You can do it in a view, but a view is not designed
to represent information, merely to present it.

Assuming you could easily state that "Julie likes everyone who likes girls"
once you converted the variable to a domain, you're still forced into a very
rigid structure. If you're in a situation where a piece of knowledge in the
database is unique for a given row, you wouldn't be able to convert everything
to domains. Consider a situation where you're representing information about
patients' blood tests. There are some basic tests that you can pigeonhole in a
domain, but what about very specialized tests that only a handful of patients
ever take?

I think this is definitely a case of Blub for both of us. If we were to be set
free from the relational way of thinking, we'd be solving problems we can't
even think up now.

