Re: Eliminating Combinatorial Relationship Multiplication

--CELKO-- wrote:
> Here is the link on Amazon.com for my new book on "Trees & Hierarchies
> in SQL"
>
> http://www.amazon.com/exec/obidos/tg/detail/-/1558609202/qid=1080772873/sr=1-1/ref=sr_1_1/102-7683601-6345721?v=glance&s=books#product-details
>
> Separate the tree structure from the nodes. Ilike the nested sets
> model for the structure, but you can pick whatever works best for your
> situation. Then the nodes can go into another table.

<snip a clever way of storing tree structures>

I have a couple of questions:

1. What's to stop you putting extra information into the Sedans or SUV tables (like descriptions etc.) instead of creating separate tables?
2. Do you think it would be good to have primary keys that span two tables in order to get rid of the vehicles table? Would there be any disadvantage to doing it this way instead of the way you outlined?

John

PS: Apologies in advance for (predictably) missing obvious things. Received on Thu Jul 01 2004 - 10:49:17 CDT