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Particularly Big O and P/NP and so on - but that was for my exams and that was a looooong time ago. Predictably, out at the coal code face they never got used, so they went into archive storage and were left on a bus when drunk one night I suspect.
I could probably drag bits out, and refresh my memory of how to do 'em pretty quickly, but ... if I haven't used it for 40 years, I probably don't need to know it in the real world.
Sent from my Amstrad PC 1640
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!
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About 10 years ago, I possessed some rote memory about those things in order to get past exams and whatnot.
The only thing that ever stuck (and which no-one ever questioned me about..) was the practical application of those things.
For example, I couldn't tell you the specifics of Big O, but I know nested loops in algorithms scale poorly and O(whatever) expresses how well an algorithm scales.
I have an approximate knowledge of many things.
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That's probably why most databases aren't normalized and pretty awful
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Yeah - an education system that rewards short term retention doesn't help in the long run...
Sent from my Amstrad PC 1640
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!
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Which is surprising considering how straightforward the definitions really are:
1NF: atomic values, unique rows, unique columns
2NF: 1NF, no partial dependencies
3NF: 2NF, no transitive dependencies
BCNF: 3NF, no NP->P dependencies
4NF: BCNF, no multi-valued dependencies
5NF: Honestly I never remember this off the top of my head, I know it's an edge case of 4NF though.
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The key, the whole key, and nothing but the key. That's 3NF, innit?
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Yep yep
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It's a bit pedantic but it's also worth mentioning the common extended saying "Data depends on the key, the whole key, and nothing but the key" is actually BCNF; the 3NF version would be "Non-key data depends on the key, the whole key, and nothing but the key."
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The sentence explains how to reach 3NF - and it is not mine, but Codds.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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