Talk:Database normalization

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Karnaugh map

How would I know if I had reached the most normalised/optimised stage? Is there any tool like Karnaugh map that lists all permutations/combinations?Anwar (talk) 13:01, 22 May 2008 (UTC)[reply]

I don't know, but for small schemas (say, 20 relations or less) this is easy to see. A related issue is that there may be implicit dependencies that have not been marked explicitly in the database schema - determining those is not so easy, see e.g. [1] Rp (talk) 08:49, 7 July 2009 (UTC)[reply]

Trade-off

The article does not explain the trade-offs suffered with normalisation. For instance, a highly normalised database needs more tables each stripped to the bare minimum. So serving a singular query would require pulling data from several tables. This costs time and money. In a way, the business process is not optimised (though the database is!).Anwar (talk) 13:18, 22 May 2008 (UTC)[reply]

Do you have an article or a computing paper where this is explained, so we can add it better to the article? --Enric Naval (talk) 11:43, 24 May 2008 (UTC)[reply]

Denormalization

The statement, "It has never been proven that this denormalization itself provides any increase in performance, or if the concurrent removal of data constraints is what increases the performance." needs more backup on that argument or needs to be revised or removed. Volomike (talk) 12:53, 17 January 2009 (UTC)[reply]

It's wrong. Denormalization doesn't remove data constraints. It just means that instead of maintaining two tables, you maintain their join. This can be faster if you often need that join. Rp (talk) 21:13, 1 July 2009 (UTC)[reply]

PS the article should bother to explain this. Rp (talk) 21:19, 1 July 2009 (UTC)[reply]

Agreed. 99.60.1.164 (talk) 17:13, 22 August 2009 (UTC)[reply]

Request for normalization

Please help with http://strategy.wikimedia.org/wiki/Proposal:Assessment_content and http://strategy.wikimedia.org/wiki/Proposal_talk:Assessment_content#Normalization_of_assessment_items_.28questions.29_in_database 99.60.1.164 (talk) 01:37, 23 August 2009 (UTC)[reply]