Re: Data Modeling "the third way ?"

dario.rossa_at_mature.be said...
> Hi,
>
> Few days ago I head a discussion on data modeling.
> To me , at least what I know about data modeling there are two ways
> (or two families) to model "the real world" the data of your business
> model.
> 1. Dimensional modeling , Star Schema....
> 2. Entity Relationship modeling , ERD , 3NF ..or E-ER modeling..say
> the OO way.
>
> But he had following modeling technique...
>
> - No relationships between tables.
> - Table A contains in one of the columns the name of the related table
> - Table A contains the record number of the related table, mentioned
> in the column above.
>
> It seems to me that this is not maintainable and to get or insert data
> you almost need to implement a database engine yourself to update
> record numbers...etc.
> No mapping possible to EJB CMP or whatever technology to retrieve or
> store data.
>
> His argument is : It is flexible...you can store everything...
>
> But what are you modeling....This is not a model to me and not usable.
>
> Happy to hear some comments on this one...."the third way"
>
> //The truth is out there
>
>
> Regards,
>
> Dario
> dario.rossa_at_mature.be
>

Well, that is a very unusual way of doing a physical design. However, unless Table B in your example has a "next" link in it, then he can't implement anything except a one:one relationship. It almost reminds me of my old IDMS or SAS-S2K hierarchical database days, where records were created as prior/next linked lists.

I'd hate to maintain a database like your peer suggested. I can't tell you how many late nights I tried to repair broken links in those linked lists DBs ... by starting at the first record in the list and moving forward to the broken link, then starting at the last record and moving backward to the broken link, then linking those two records together.

Tell your peer that one old goat (me) has worked with databases like he or she is proposing ... and thank the stars that someone invented the RDBMS! What a nightmare it used to be! But I suppose there will always be those who studied linked lists in their college days and think that's the greatest thing ever invented. Just remember, absolute flexibility has its price ... and penalties. Are you willing to pay the price?

-- 
/Karsten
DBA > retired > DBA