In "Young Frankenstein", The Doctor asks Eye-gor (Igor) whose brain he *really* retrieved. Igor replies, "Abby Normal?" I've spent the last hour or so wandering amongst some web sites, blogs, and whitepapers which seek to explain Normal Forms to normal folks; no math, just words.
This one says this: "'Normalization' just means making something more normal, which usually means bringing it closer to conformity with a given standard." Alas, not even close.
Which, since I've been re-reading my probability, stats, and stat pack books and docs, this flipped a switch. Which switch leads to a clearer, albeit slightly mathematical, definition.
I've done a quick search, and can't confirm that he explicitly said so, but given that Dr. Codd was trained as a mathematician, I'll surmise that he used the word in the following sense. In math, two terms are used as synonyms, orthogonal and normal. Remember from geometry class that a 90 degree line is the normal line? It's also orthogonal. Orthogonal as a concept means independence of influence (just as the X axis is independent of the Y axis; there some math), and Codd uses that term liberally in his paper.
So, the normal forms have nothing to do with not insane or seeking standards, but with data independence. Which is normal.
Despite what the reactionaries assert, the world is not flat nor is it hierarchical. The world is relational. Infinite granularity yields infinite complexity.
Vaccinated ≠ Not Infectious
$536,800,000 MARF™(party like it's 1829)
-- New York Slammers, so far/2024 [GA and The Feds still to come]
-- New York Slammers, so far/2024 [GA and The Feds still to come]
Covid-19 has killed at least 1,123,836 people (as of 20 March 2023, final update)
Scientists aren't vocal enough about science. There are large groups of people who think scientists are all frauds and who don't
believe in science, and they're being cultured by some of our far right-wing politicians, religious leaders and community leaders. -- Drew Weissman/2022
To date, Microsoft is stating that organizations testing In-Memory OLTP have
seen transaction speeds improve by up to 30 times compared to past
performance, with the best performance gains achieved when the business
logic resides in the database and not in the applications.
-- Jonathan Watts/2015 [my emphasis]
-- Jonathan Watts/2015 [my emphasis]
I have had to explain and re-explain and re-explain and re-explain, you know, how relational databases work, what is an eigenvector,
what is dimensionality reduction.
-- Christopher Wylie/2018
... but Flash-based storage has such a different performance profile from rotating media, that I suspect that it will end up having
a large impact on filesystem design. Right now, most filesystems tend to be designed with the latencies of rotating media in mind.
-- Linus Torvalds/2007
-- Chris Date/2009
This week's thought
[The intelligence community] argued that [the restrictive amendment] would cripple the program because they typically use it before there is enough evidence to meet a standard of probable cause for a warrant, like early in investigations when they are trying to learn more about a phone number or an email account found to be in contact with a suspected foreign spy or terrorist. -- Charlie Savage/2024 [IOW, let's catch the thief before the horse is out of the barn - the MARF™(party like it's 1829) traitor's worst nightmare]
In a time of SSD, multi-core/processor, two terabyte memory and Optane App Direct Mode machines, there is no reason not to
build from BCNF data. Time to do what Dr. Codd demonstrated. Technology has finally caught up with the maths.
About
- Robert Young
- Been doing databases, both relational and others, as well as operations research since Hector was a Pup.
Shameless Plug
I know a little something about SQL, DB2 (preferably LUW, z/OS if the money's right), Oracle, SQL Server, Postgres, and database design in general. Mentoring/teaching/consulting on a short term basis, too. And a bit of stat analysis if it's R.
gnuoytr at rcn dot com.
gnuoytr at rcn dot com.
3 comments:
The paper is on the internet in several places under a "A relational model of data for large data banks"
http://www.seas.upenn.edu/~zives/03f/cis550/codd.pdf
Yeah, that was the one I re-read, but not his later work. He uses "normal" without offering an explicit definition, leading me to conclude, given that he describes the goal as data "independence", that he was using it as a math term. Which means orthogonal, which ends up being independence.
And, of course, that's precisely what one gets proceeding to the higher normal forms: greater explicit and structural data independence.
I'll go with that. Plus, for the non-insane / standard form, there's the word "canonical".
For example, in complex logical expressions (which can be written in different ways, depending on which variables or sub-expressions are factored out), one can always get down to a sum-of-products canonical form.
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