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Re: _item.mandatory_code can be undefined! (plus other development

John Westbrook (jwest@ndbdev.Rutgers.EDU)
Fri, 11 Aug 1995 13:07:26 -0400 

On Aug 11,  4:01pm, Peter Keller wrote:
> Subject: Re: _item.mandatory_code can be undefined! (plus other developmen
>
> In the light of your comments, I guess that given that _item.name has to
> be there, _item.mandatory_code is necessary to avoid the possibility of
> partial row updates. Since I wasn't around for the discussion I don't know
> the arguments for re-specifying the ITEM category at all, and I find it
> hard to see why it was thought necessary. If there is simply a requirement
> for the data item's name to be repeated somewhere within the save frame,
> it might be better to do this with _item_description.name, rather than
> _item.name. This would then avoid the need to re-specify
> _item.mandatory_code. Both the ITEM_DESCRIPTION category, and the
> _item_description.description item, are mandatory anyway, so this would be
> a good way to do it. (Making this change might seem to involve some hard
> work at first sight, but I could kludge my own code to do it fairly
> quickly, if necessary.)
>
This is certainly a good alternative but the requirement was that there be
a single standard data item like _item.name for each definition.

> Personally I'd be very happy with that. I take it that you are suggesting
> that _item.mandatory_code should be "inherit" for _item_type.code? From my
> own work, I am starting to realise that these are the two items which are
> really crucial in the handling of real data - if there are problems with
> them, there is no way out.

We will experiment with this a bit and then incorporate it in the next
version of the DDL if there are no objections raised.
>
> Am I right in thinking that the _category.mandatory_code item for the
> ITEM_TYPE category should then also be changed to yes, since all of its
> member items would have a mandatory code of implicit or inherit? I guess
> that the likely impact on the dictionaries should be the main
> consideration here.
>
I do not think that we have to go this far.  It may be that some folks would
develop local dictionaries without this requirement.


Regards...

John


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