title: Is a fact table in normalized or de-normalized form?
body: <p>I did a bit R&amp;D on the fact tables, whether they are normalized or de-normalized. 
  I came across some findings which make me confused.</p>
  
  <p>According to <a href="http://www.dwbiconcepts.com/business-intelligence-forum/fact-table-is-normalized-or-denormalized-form.html" rel="noreferrer">Kimball</a>:</p>
  
  <blockquote>
    <p>Dimensional models combine normalized and denormalized table structures. The dimension tables of descriptive information are highly denormalized with detailed and hierarchical roll-up attributes in the same table. Meanwhile, the fact tables with performance metrics are typically normalized. While we advise against a fully normalized with snowflaked dimension attributes in separate tables (creating blizzard-like conditions for the business user), a single denormalized big wide table containing both metrics and descriptions in the same table is also ill-advised.</p>
  </blockquote>
  
  <p>The other finding, which I also I think is ok, <a href="http://www.geekinterview.com/question_details/30488" rel="noreferrer">by fazalhp at GeekInterview</a>:</p>
  
  <blockquote>
    <p>The main funda of DW is de-normalizing the data for faster access by the reporting tool...so if ur building a DW ..90% it has to be de-normalized and off course the fact table has to be de normalized...</p>
  </blockquote>
  
  <p>So my question is, are fact tables normalized or de-normalized? If any of these then how &amp; why?</p>