Another, perhaps better way, perhaps not, assuming that the order status is 
available in a list
table would be:

SELECT OrdNumber, OrderStatus FROM UPSOrders +
  WHERE OrderStatus NOT IN (SELECT OrderStatus FROM LstOrderStatus)

--- [EMAIL PROTECTED] wrote:
> This is not a major issue, just wanting to understand code better.
> Why do I get a different result on the below select commands?
> 
> R>sel ordnumber orderstatus from upsorders where orderstatus not exists
>  ordnumber              ordersta 
>  ---------------------- -------- 
>  OR333910               -0-
>  OR333911               -0-
> R>sel ordnumber orderstatus from upsorders where orderstatus is null
>  ordnumber              ordersta 
>  ---------------------- -------- 
>  OR333911               -0-
> 
> Also note that the "not exists" statement takes much longer to 
> return the selection than the "is null" statement which is almost instant.
> 
> I had a snippet of code that was not finding all the records. Simply changing 
> it to not exists
> fixed the problem, but I was wondering what the difference is.
> 
> Thanks,
> -Bob

Albert Berry 
Management Consultant
RR2 - 1252 Ponderosa Drive
Sparwood BC, V0B 2G2 
Canada
(250) 425-5806
(250) 425-7259
(708) 575-3952 (fax)
[EMAIL PROTECTED]

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