Home Page for the TeradataForum

Archives of the TeradataForum

Message Posted: Wed, 04 Apr 2001 @ 16:57:45 GMT

  <Prev Next>   <<First <Prev Next> Last>>  

Subj:   Re: Primary keys in Fact tables for Star Schemas
From:   John K. Wight


Welcome to the fold and I hope that your classes go well. I have seen many new customers with the same skepticism but given an amount of time and experience, they usually come around to understanding that Teradata does actually work well with 3NF for DSS applications. Oh, it can also to 'star schemas' and hybrids of 3NF and star schema (seen them all). I think that the big thing for me has always been the SQL you have to use to create/load/maintain star schemas which can be much more cumbersome and the ETL processes can be much more intensive to repeatedly maintain pure start schema implementations. This is only 12 years of experience on my side so I don't claim to know them all, but having actually worked with both, I think you will eventually see that 3NF if much easier to create and maintain.

We all know the Start Schema was 'invented' by a guy (you all know who) whose technology was not really relational and the only way it would work was with a 'star schema' approach where the paths were clearly defined (not usually associated with a true DSS environment where many of the questions are usually still unknown). His technology also imposed a limitation that you could not access the database when it was being updated and that was only in batch mode!

I don't mean to suggest that a Start Schema is no good with Teradata, they work well there too - just not necessary!

To quote a recent new customer who finally saw the light about Teradata and its ability to do 3NF (and all the other good stuff in DSS), ". . . I had to touch the wounds"!

John K. Wight
Teradata Certified
Senior Solutions Consultant - Teradata (a division of NCR)

  <Prev Next>   <<First <Prev Next> Last>>  
  Top Home Privacy Feedback  
Copyright for the TeradataForum (TDATA-L), Manta BlueSky    
Copyright 2016 - All Rights Reserved    
Last Modified: 28 Jun 2020