sathiyanarayanan

• Nov 17th, 2005

 

ans:- a diamension which does not changes the grain level is called junk diamension.

grain- lowest level of reporting.

Sreenivas Poondru

• Jan 3rd, 2006

 

"The junk dimension is simply a structure that provides a convenient place to store the junk attributes"

kiranbandari

 Profile Answers by kiranbandari 

• Mar 16th, 2006

 

A junk dimension is a convenient grouping of flags and indicators.

swift_s

 Profile Answers by swift_s 

• Jun 11th, 2009

 

A "junk" dimension is a collection of random transactional codes, flags and/or text attributes that are unrelated to any particular dimension. The junk dimension is simply a structure that provides a convenient place to store the junk attributes. A good example would be a trade fact in a company that brokers equity trades. The fact would contain several metrics (principal amount, net amount, price per share, commission, margin amount, etc.) and would be related to several dimensions such as account, date, rep, office, exchange, etc. This fact would also contain several codes and flags that were related to the transaction rather than any of the dimensions ... such as origin code (that indicates whether the trade was initiated with a phone call or via the Web), a reinvest flag (that indicates whether or not this trade as was the result of the reinvestment of a dividend payout) and a comment field for storing special instructions from the customer. These three attributes would normally be removed from the fact table and stored in a junk dimension ... perhaps called the trade dimension. In this way, the number of indexes on the fact table would be reduced, and performance (not to mention ease of use) would be enhanced. Hope this helps.