DM Vs ER

[coggykid]

can anyone tell me some basic advantages / disadvantages of Dimensional Modeling and ER Modeling.

thanks

 

[doubt76]

Hi,

The differences to my knowledge are,

Dimensional modeling
1. Data warehouse environment
2. Easy User understandability
3. Increases query performance
4. Mostly data is in denormalized form

ER modeling
1. OLTP Environment
2. Difficult user understandability
3. Query performance is slower
4. Data should be in normalized form

I think this will help you.

Mahesh

 

[DWKnight]

Hi ..

You might also would like to take a look at this :

http://www.ciobriefings.com/whitepapers/StarSchema.asp

Regards,
DWKnight.

 

[tdatgod]

Hi,
you might want to read chapter 4 and 5 of the Teradata RDBMS Database Design manual. It talks about ER vs DM and why each is good for what it does.

(File Size: 2,658,626)

http://www.info.ncr.com/dload.cfm?itemid=011900001

It also has references at the end of each chapter of other reading material.