Re: Normalizing vs. Denormalizing

There are several performance techniques you can use to improve the performance of your system including caching schemes, indexing, fast disk access, SGA, and shared_pool.....etc. By denormalization you are really defeating the purpose of relational database. Remember that once you develop a system it is not EASY to make changes later. Remember you are not just storing DATA but translting your way of doing business and rules into an information system, and if your system is not normalize, you won't be able to utilize the new concepts (Data mining, Data warehousing....etc.) to there full potential. This means that you have to spend time and effort down the road (probably very soon)on your existing system. RDMS such as Oracle are designed to handle normalization very well even with the basic configuration and with a help of a good DBA you can design a 3rd or even 4th deg. normalize system without any significant performance problem. Consider demormalization only when the performance is "NOT ACCEPTABLE".

Shariq Mansoor
e-mail shariq_at_uh.edu

EPepa (epepa_at_aol.com) wrote:
: I'm in the process of helping to develop an Oracle database for a plant
: that's very concerned with speed. They enter about 5000 orders per month
: and each order is one record (no detail lines). Since I took the Oracle
: classes, I have the normalization techniques down pretty well, but my
: concern is the time that it would take in disk reads in order to access
: the several tables required to normalize this company's orders. (Each
: order should store information into several tables that would have 4-5
: sets of 5-10 pieces of data each, for a total of about 35 denormalized
: columns.) If I denormalize the data, it would reduce the number of disk
: reads and all of the information should be fairly contiguous, but it seems
: to me that that would defeat the purpose of a relational database.
 

: Does anyone have any ideas on where you would draw the line?
  Received on Tue Mar 19 1996 - 00:00:00 CET