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Re: NULL, N.A., Undefined, Unknown values

John Westbrook (jwest@wormhole)
Thu, 19 Jan 1995 11:10:35 -0500 

On Jan 19, 10:30am, Jean Richelle wrote:
> Subject: NULL, N.A., Undefined, Unknown values
> Hello,
>
> This question is directed specifically to John Westbrook but others may
> have enlignments on the subject.
>
> I wonder how it is possible to specify NULL, N.A. (Not Applicable),
> Undefined, Unknown values for data items of any types. I don't remember
> nothing regarding this in the DDL.
>
> Jean

>-- End of excerpt from Jean Richelle

Hi Jean,

Yes we define the question mark (?) to indicate that a data item is missing in
a file and we define the period character (.) to indicate that there is no
appropriate value for a data item.


Regards,

John


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