Re: Looking for a way to implement SQL-92 Domain

On 24 Mar 2003, wizofoz2k_at_yahoo.com.au.nospam wrote:

> Domain tables are a very good way of reducing clutter, BTW.
> Nothing wrong with using them in Oracle with triggers.

I guess it depends on one's definition of clutter. :-) The full picture of tables gets really large with lots of lookups but the amount of trigger code is increased the same amount and I would venture a guess that maintaining an RI relationship in a datamodeling tool is much easier than maintaining its analogous trigger.

> Of course, you can ALWAYS generate your views with a join
> to the domain table using the key as join column, the value
> as part of your return list and the domain value as a constant.
> Works a treat. But not directly updatable without some added
> complexity.

I just use submodeling in Erwin. I have a naming standard on the column where the postpended string "_lkp" signifies that there is some table out there with the lookup values. I don't show these tables in the pictures of the model, the developers just know they exist and can select from them if needed.

So then the "clutter" is minimized and I don't have to maintain triggers. The RI is maintained by the database.

-- 
Galen deForest Boyer
Sweet dreams and flying machines in pieces on the ground.