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121 points b-man | 1 comments | | HN request time: 0.209s | source
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AnonHP ◴[] No.44026428[source]
Seems like this article places too much emphasis on normalization, which is appropriate for many cases, but may be a huge cost and performance issue for requirements like reporting. You may probably need different kinds of schema and data storage structures for different requirements in the same application, which in turn may result in duplicated data, but results in acceptable trade offs.
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weinzierl ◴[] No.44026552[source]
" Every base relation should be in its highest normal form (3, 5 or 6th normal form). "

If I remember my database lessons correctly there is no strictly highest normal form. It progresses from 1NF to BCNF, but above that it is more choosing different trade-offs.

Even below it is always a trade-off with performance and that is why we most of the time aim for 3NF, and sometimes BCNF.

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1. plank ◴[] No.44027374[source]
There are big disadvantages from choosing e g. 5th normal form: any changing in business requirements leads to a big rewrite and data conversion. Never seen successful projects choosing beyond 3rd/BCNF.