Re: delete cascade
From: paul c <toledobythesea_at_oohay.ac>
Date: Mon, 16 Apr 2007 22:17:16 GMT
Message-ID: <MBSUh.83937$DE1.76718_at_pd7urf2no>
>
>
> No. One states that deleting the invoice automatically deletes any items
> that exist. The other states that one may not delete an invoice when any
> items exist.
Date: Mon, 16 Apr 2007 22:17:16 GMT
Message-ID: <MBSUh.83937$DE1.76718_at_pd7urf2no>
Bob Badour wrote:
> paul c wrote:
>
>> Bob Badour wrote: >> >>> paul c wrote: >>> >>>> I sometimes wonder why the above noun used in place of an adjective >>>> is needed. When the table/relation definition of a line item >>>> references an invoice number can it mean anything other than that >>>> the line item doesn't exist unless the invoice exists? Ie., why >>>> shouldn't delete always mean so-called "cascade"? >>>> >>>> (just trying to keep Marshall interested.) >>> >>> >>> >>> Because some times it means: "If a line item exists, the invoice must >>> also exist." >> >> >> >> Please forgive my thickness, but doesn't "line item doesn't exist >> unless..." (ie., "only if") "...the invoice exists" mean the same?
>
>
> No. One states that deleting the invoice automatically deletes any items
> that exist. The other states that one may not delete an invoice when any
> items exist.
p Received on Tue Apr 17 2007 - 00:17:16 CEST