G*O 发帖数: 706 | 1 3NF? BCNF? or others?
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w*******e 发帖数: 1622 | 2 3NF
【在 G*O 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 3NF? BCNF? or others? : Thanks!!!
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G*O 发帖数: 706 | 3 你估计占多大比例?thanks
【在 w*******e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 3NF
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x***e 发帖数: 2449 | 4 if you are using nomalization, more than 80%
【在 G*O 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 你估计占多大比例?thanks
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G*O 发帖数: 706 | 5 为啥其他normal form不重要呢?谢谢!
【在 x***e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : if you are using nomalization, more than 80%
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w*******e 发帖数: 1622 | 6 这问题有点大, 还得未来BM出马啊
【在 G*O 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 为啥其他normal form不重要呢?谢谢!
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x***e 发帖数: 2449 | 7 let us say this way, it is not that the others are not important.
it is more like the others are not as practical as 3nf.
Do you think all DB developers are at least holding a MS degree? :)
【在 G*O 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 为啥其他normal form不重要呢?谢谢!
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G*O 发帖数: 706 | 8 我觉得可能还是技术角度的原因,而不是人的能力的原因。
normalization程度越高,redundancy越少,integraty越好,但是performance会下降
我奇怪为啥3NF会占这么大比重,是cost effectness特别好么?
【在 x***e 的大作中提到】![](/moin_static193/solenoid/img/up.png) : let us say this way, it is not that the others are not important. : it is more like the others are not as practical as 3nf. : Do you think all DB developers are at least holding a MS degree? :)
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x***e 发帖数: 2449 | 9 it depends, I guess.
for datawarehousing, people do denormalization more than normalization.
even lots of referential integraty is bypassed.
you might right, performance is probably the main reason.
【在 G*O 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 我觉得可能还是技术角度的原因,而不是人的能力的原因。 : normalization程度越高,redundancy越少,integraty越好,但是performance会下降 : 我奇怪为啥3NF会占这么大比重,是cost effectness特别好么?
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a*******t 发帖数: 891 | 10 3NF takes care of all common data abnormines
without a valid reason, it is not desirable to go above 3NF
it's like, there are 4 cyl engines, 6, 8, 12 cyl engines. why is 4 cyl the
most popular?
【在 G*O 的大作中提到】![](/moin_static193/solenoid/img/up.png) : 我觉得可能还是技术角度的原因,而不是人的能力的原因。 : normalization程度越高,redundancy越少,integraty越好,但是performance会下降 : 我奇怪为啥3NF会占这么大比重,是cost effectness特别好么?
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