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Posted Thursday, August 29, 2013 11:56 PM
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can anybody explain me about 5 normal form ? I have searched the internet but I am not convinced!
please help
Thanks and Regards
Post #1490008
Posted Friday, August 30, 2013 8:12 AM


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Simply put, tables are in fifth normal form when they comply with fourth normal form and the table consists of a key attribute and a non-key attribute ONLY.

Francis
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Post #1490177
Posted Friday, August 30, 2013 2:41 PM


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Have you read wiki? http://en.wikipedia.org/wiki/Database_normalization

Also Refer these links:
http://www.dotnetspider.com/forum/161909-Any-one-explain-roles-5-normal-forms.aspx
http://blog.todmeansfox.com/2007/12/04/database-design-4th-and-5th-normal-forms/
Post #1490312
Posted Friday, August 30, 2013 3:21 PM


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Francis Apel (8/30/2013)
Simply put, tables are in fifth normal form when they comply with fourth normal form and the table consists of a key attribute and a non-key attribute ONLY.

That's a remarkable idea - it seems to say that a table in 5NF can't have more than 2 attributes. Not surprisingly, that is not correct, for example a historized attribute table in Anchor Model (see the Wikipedia article on Anchor Modelling) has 3 attributes but is in (Date's version of) 6NF and hence also in 5NF.

Gurjer, did you look at the Wikipedia page on 5NF? If so, look at it again but instead of "travelling salesman" think "person with an agency agreement with one or more manufacturers", and instead of "telescope" think "hat stand" - you may well find that the example is much more believable like that, and that will perhaps make it easier to understand. If that doesn't help, say so in this forum and I'll try to find time to do a better explanation for you.


Tom
Post #1490316
Posted Monday, September 2, 2013 1:00 AM
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thank you all I think i got it
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