Talk:Snowflake schema

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the first and fourth paragraphs were directly stolen from this oracle documentation ("snowflake schemas section"): http://www.lc.leidenuniv.nl/awcourse/oracle/server.920/a96520/schemas.htm#12915

so I'm going to remove them

This copyvio was the initial start of the page, so is in all older versions of the page. Maybe the page should be deleted and rewritten from scratch? In particular since without the original copyvio information, the current version of the page is not really understandable to a non-expert. -- S.K. 17:14, 2 March 2006 (UTC)

[edit] First and last paragraphs deleted on January 13,2006 be brought back

Hello!

I am the one who wrote the first and the last paragraphs of the article on Snowflake schemas which have been deleted. You have my assurance that the resembelence of the first and the last paragraphs is purely coincidental. I work on SQL Server data warehouses day in and day out. Those lines were a result of my own understanding on the same. Just because a certain resembelence was found doesn't mean that those were copied. Also, you cannot say something is "Copied" or that someone is a "thief" without any proof.

I demand that those lines be brought back into the article, else I will do that myself.

Also, tell me, in case you find something similar to other articles on the web (say for eg. A typical "Hello World!" program), do you keep deleting the stuff? That way, everything should be scrapped off, isn't it?

-Nakul

Mate, it's not a matter of a certain `resembelence' (whatever that is) between your supposed writing and something else. Those two paragraphs are word-by-word copies of the Oracle documentation (19: Schema Modelling Techniques). What more evidence is needed 118.92.75.85 (talk)

[edit] Some cleanup and context as requested

  • Some sources regard snowflake and star schema a separate ideas, others that snowflake is a variation on star. I've allowed for either interpretation
  • Added a quick definition of multidimensionality
  • Put the nub of the difference between star and snowflake schemas towards the top of the article
  • Replaced "Relational databases consisting of a single fact table with a compound candidate key, with segments for each "dimension" and with additional columns of additive, numeric facts." with the term star schema, since this is the definition of a star schema and the technical terms "compound key" and "candidate key" are not otherwise required.
  • removed the paragraph containing the PoV statement "few business queries that management likes to run"
  • Added reasons why snowflaking might be a good idea
  • reordered some of the paragraphs so that the explanation of a term was before or immediately after its first usage
  • made the point that users might use star or snowflake schemas to form a query, regardless of the physical storeage model

Allandean 09:14, 6 September 2006 (UTC)

Have made changes in the introductory paragraphs for better readability. Comments are invited for further improvements.

[edit] Seeming contradiction (to non-expert) in snowflake and star articles

If I read this correctly, the snowflake schema article says there will always be one fact table, while the star schema article says that there will often be multiple fact tables, and that when there is a single fact that this makes the star a star. I don't know which is accurate, but to a lay reader this seems a contradiction and is confusing. I'd encourage an expert on the subject to compare these two statements (near the top of each article) and amend for consistency. -Jeff Jebbo (talk) 15:37, 14 May 2008 (UTC)