Re: Regarding Database Design

From: Preston <dontwantany_at_nowhere.invalid>
Date: 11 May 2009 08:21:11 GMT
Message-ID: <76q5fnF1diakaU1_at_mid.individual.net>



DeB wrote:

> Hi Faculties,
>
> Please accept my apologies if this query is out of context of the
> discussions in this forum.
>
> I've with me a proposed database design which is not normalized
> fully. There are some other tables that we plan to denormalize. The
> targeted database platform is Oracle Database 10g Release 2.
>
> For ex:- We have a table called user_groups which links the users
> and the groups table. But now we are thinking to eliminate this table
> and have a group_ids column storing comma separated values of groups
> ids from the groups table instead.

Yuck!

> The records will look like -
>
> groups
> ------
>
> group_id group_name
> 1 Admin
> 2 Operator
> 3 Power User
>
>
> users
> ------
>
> user_id user_name group_ids
> 1 User1 1,3
> 2 User2 2,3
>
>
> The targeted database will be a typical OLTP system. Please suggest
> if this approach to database design has any fundamental flaws.

Don't know how many groups you've got, but imagine it's n years in the future & you've now got 15+, & someone asks for a list of all users in both the Admin & Power User groups; how will you write that query?

-- 
Preston
Received on Mon May 11 2009 - 03:21:11 CDT

Original text of this message