Storing "derived" values vs calculating them on extraction

Posted by kemp on Stack Overflow See other posts from Stack Overflow or by kemp
Published on 2010-04-21T07:22:54Z Indexed on 2010/04/21 7:33 UTC
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database

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database-design

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best-practices

When you have values which only depends on one or more other fields +/- constants (say retail price & discount price), is it better to store those values too or to calculate them "on the fly" when retrieving the data?

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