Re: atomic
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Wed, 31 Oct 2007 16:46:10 -0300
Message-ID: <4728db84$0$14867$9a566e8b_at_news.aliant.net>
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> I think it means that relational algebra operators are not allowed to
> decompose it.
Date: Wed, 31 Oct 2007 16:46:10 -0300
Message-ID: <4728db84$0$14867$9a566e8b_at_news.aliant.net>
>> On Oct 31, 4:31 pm, "Roy Hann" <specia..._at_processed.almost.meat>
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>>> 1NF does not *require* that values be atomic. It asserts that values >>> will >>> be *treated as* atomic. Big difference. Essential difference. >>> >>> Roy >> >> Can that be formalised? I agree with Bob that in general we have a >> set of operators and they can allow us to see internal structure. >> What does it mean for a value to be *treated* as atomic?
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> I think it means that relational algebra operators are not allowed to
> decompose it.
Actually, the structure is illusory and representation-dependent. Domains have operations that appear to reveal internal structure even when that internal structure may not physically exist. Received on Wed Oct 31 2007 - 20:46:10 CET