Databasen - NULL dates

Dave Cross dave at
Wed Oct 18 11:56:46 BST 2006

Quoting Nigel Rantor <wiggly at>:

> We got into a discussion about whether or not to use NULL values for
> dates that are as-yet-unknown. anyone have strong feelings and
> arguments either way?
> Interested to see where people stand.

NULL is the unknown value. Your dates are unknown. Sounds like a  
perfect match to me. I'd be interested in hearing the other point of  

Twenty years ago I did some data input work. I was entering invoice  
payment dates and amounts. The system didn't allow unknown dates, so  
when it wasn't clear we were instructed to enter '31-12-99' (the  
latest date the system would allow). I hope those records all got  
cleaned up at some point, or their cheque printers would have suddenly  
have got very busy on that date.



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