You can't do that

[Jeff Harrison]

--- John Esak <john at valar.com> wrote:

> 
> Okay, it's just that I have NEVER, not even once run
> into a situation where
> there are child records with NO header record. I
> think if that happens,
> there is something improperly written.  However, I
> have heard of this
> happening to others who are the best filePro
> programmers I know... so, I
> suppose I must grant that it can happen somehow even
> to the best of us.
> Just haven't ever seen it yet. So, implementing code
> to ensure that it never
> happens, when it never has... is sort of silly to
> me. At least, there are
> hundreds of things I'd rather see in filePro first.
> 
> John
> 

John, you are lucky that you have not been exposed to
the garbage that I have seen :-)

It also seems that you are getting lost with just this
one example.  My request was for rules for data
integrity.  This would just be one of the possible
rules.

Example: I have seen many situations where the
programmer has allowed the deletion of a record such
as an an inventory record, when it is still referenced
in another file such as an order file. Ouch.

Some other possible rules would be:

Force certain field(s) to be unique.
Require a non-blank field.
Require the existence of a matching record in another
file.
Minimum/Maxium values for fields.
Math rules for field values. (Ex. Field must be an
even number)
Prevent any records from being deleted.
Require that if field A is filled in then field B not
be filled in.

These are just a few of the possibilities that come to
mind.

Jeff Harrison
jeffaharrison at yahoo.com

Author of JHExport and JHImport.  The easiest and
fastest ways to generate code for filePro exports and imports.


		
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