Re: Data Modeling Question

From: Jared Still <jkstill_at_gmail.com>
Date: Thu, 7 Feb 2008 11:26:46 -0800
Message-ID: <bf46380802071126t3811a27cxbdae27e5ae73c39d@mail.gmail.com>


On Feb 6, 2008 7:51 PM, Ahbaid Gaffoor <ahbaid_at_att.net> wrote:

> It's a developer's dream of how we can store attributes for an item, the
> item type is used to decide which column holds what attributes by
> storing that metadata in the ITEM_TYPE_LU table. Initially, some 7 years
> ago the developer only dreamed of no more than 10 attributes per item.
> Today there are 205 attributes, some fields hold data that's a few
> characters and some the full 4000 characters.
>
>

Developers sometimes see this as an 'elegant' method to store data.

Not only is it not elegant, it is quite the opposite.

Several things are guaranteed when this 'model' is used:

  • developers are writing much more code than necessary
  • performance will be terrible (and there is nothing you can do about it)
  • there will be redundant, inaccurate and missing data in the database ( developers claim otherwise. But they are *always* wrong about that)
  • the SQL gets terribly complex

*from A Practical Guide to Logical Data Modeling' by George Tillman*

(paraphrased, the book is at home)

*'The reason that there is such a great need for Data Modelers is** because developers are so bad at it.' *

-- 
Jared Still
Certifiable Oracle DBA and Part Time Perl Evangelist

--
http://www.freelists.org/webpage/oracle-l
Received on Thu Feb 07 2008 - 13:26:46 CST

Original text of this message