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From Kristian Waagan <Kristian.Waa...@Sun.COM>
Subject Re: Quering on multiple rows
Date Thu, 08 Nov 2007 18:09:31 GMT
Patrick Sp. wrote:
> Hi Stanley,
> Thank you for your response.
> This is what is actually done. My question is rather about the SQL statement
> I need to execute in order to be  able to express constraints on multiple
> rows on the Mission table related to one specific employee.
> Any help is appreciated.
> Thanks
> P. 

Hello Patrick,

Do you mean multiple rows or multiple columns?
Is there a problem with Derby not behaving as expected?

"OR", "AND" and "IN", maybe "NOT"

> ---   
> In many ways this is a matter of preference but, IMHO, since both 
> Missions and Employee seem to be primary objects and there could be a 
> M:M relationship I would create an association table with two columns 
> Mission_id and    Employee_id and, for good form, throw in a 
> auto-increment column to be used as the primary key of the table (or the 
> compound key Mission_id and Employee_id could be used as the PK).

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