Re: Please check the model for errors
Posted by: Rick James
Date: April 17, 2010 07:18PM

I prefer the iterative method.
1. sketch out ERD (you did that)
2. write CREATE TABLEs -- this might lead to some issues having to do with constraints that the database gives.
3. estimate sizes -- If this will be a 'huge' database, performance considerations need to be considered this early. Go back to #2.
4. Write the SELECTs. Oops, the ERD and/or Schema do not support some of the SELECTs; go back to step 1 or 2.
5. INSERT some data (even if it is facricated).
6. (If huge) Write a script to generate a huge amount of data. Check performance; iterate if needed.

Over-normalization can be somewhere between bad and terrible for performance on Huge tables.
Under-normalization can lead to clumsy code, mostly in the form of extra UPDATE statements when a value changes.
Normalization will lead to extra steps to look up ids, given strings. This is worth it in the long run.

Options: ReplyQuote


Subject
Written By
Posted
J D
April 15, 2010 08:13PM
April 16, 2010 10:04PM
J D
April 17, 2010 04:27PM
Re: Please check the model for errors
April 17, 2010 07:18PM


Sorry, you can't reply to this topic. It has been closed.

Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party.