GeekInterview.com
   Home |  Tech FAQ  |   Interview Questions |  Placement Papers |  Tech Articles |  Learn |  Freelance Projects |  Online Testing |  Geeks Talk |  Job Postings |  Knowledge Base | Site Search |  Add/Ask Question

  GeekInterview.com  >  Interview Questions  >  Data Warehousing  >  DataStage

 Print  |  
Question:  Importance of Surrogate Key in Data warehousing? 



Answer: Surrogate Key is a Primary Key for a Dimension table. Most importance of using it is it is independent of underlying database. i.e Surrogate Key is not affected by the changes going on with a database. 



September 09, 2006 09:41:55 #3
 OM PRAKASH BANG Microsoft Expert  Member Since: March 2006    Total Comments: 46 
RE: Importance of Surrogate Key in Data warehousing?&n...
 

I slightly differ from the reply posted by Mr. Abhishek

Surrogate Key should be system generated number and it should be small integer.  For each dimension table depending on the SCD and no of total records expected over a 4 years time, you may limit the max number.  This will improve the indexing, performance, query processing.

     

 

Back To Question