Database Normalization

[weird0]

I know that is not the appropriate group for asking this question,
but I do not know of any better forum.

Can anyone plz explain clearly what normalization is? The first three
normal forms upto 3NF and BCNF. I know the first one but the remaining
ones are really confusing. The language changes dramatically into
functional dependencies x---> y, all that, and normalization, the real
topic is lost in between.

Decent explanation or good links would be highly appreciated.

Regards

 

[Lasse Vågsæther Karlsen]

I know that is not the appropriate group for asking this question,
but I do not know of any better forum.

Can anyone plz explain clearly what normalization is? The first three
normal forms upto 3NF and BCNF. I know the first one but the remaining
ones are really confusing. The language changes dramatically into
functional dependencies x---> y, all that, and normalization, the real
topic is lost in between.

Decent explanation or good links would be highly appreciated.

Regards

4NF: http://en.wikipedia.org/wiki/Fourth_normal_form
5NF: http://en.wikipedia.org/wiki/5NF
DKNF: http://en.wikipedia.org/wiki/Domain/key_normal_form
6NF: http://en.wikipedia.org/wiki/6NF
(6NF actually leads to the main page about normalization)

Note that it isn't given that you should strive for 6NF on a table just
to get to 6NF. From what I remember, 4NF and up imposes criteria on your
tables that you might not want to do.

Remember, normalization is about avoiding data redundancy and keeping
integrity, it is not about optimization.

If you read the main article about normalization, found here:
http://en.wikipedia.org/wiki/Database_normalization

then in the opening paragraphs it says: "Higher degrees of normalization
typically involve more tables and create the need for a larger number of
joins, which can reduce performance."

 

[yugip]

hello,

yeah this is somewhat wrong forum to post the questions like this
but any ways here is the link you can use for your information

http://www.cs.sfu.ca/CC/354/zaiane/material/notes/Chapter7/node12.html

hope this works