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Re: irrelevant objects in a row



On Sat, Sep 27, 2003 at 03:30:59AM +0200, Juergen Quittek wrote:
 
> I have a table of midcom policy rules. A table entry contains an
> enum object called ruleType indicating the kind of rule of this row.
> 
> Now, for describing policy rules, not always all columns are required.
> For certain values of the ruleType object, some columns are irrelevant
 
First of all, you really want to specify what happens to the cells that 
are irrelevant. I a perfect world, those cells would just not exist
(typically called table holes) and applications would just deal with
this. However, due to the implications holes have on getnext/getbulk
ordering, not all applications and tool sets will find holes easy to
deal with. So someone with tools that are not smart wrt. holes would
certainly prefer to have suitable "null" values defined.

I would suggest to take the holes approach and to document it clearly.
You will then see whether someone complains loudly that this breaks
his/her tool environment.

/js

-- 
Juergen Schoenwaelder		    International University Bremen
<http://www.eecs.iu-bremen.de/>	    P.O. Box 750 561, 28725 Bremen, Germany